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Report 98-16




FEBRUARY 28, 1998


[The original, correctly formatted version exists at: EricKrauseReports/9816.wpd ]



There were relatively few closed ceilings, and most were to be found in the half-storeys of buildings with knee walls that increased attic head room by 2 or 3 pieds. Often the boards for closing in the ceiling were applied to the low vertical knee wall, to the slope of the rafters, and to the underside of the joists. Otherwise, they went on top of the joists, in the open ceiling manner, creating a useful space above. In either case, the boards were planed, one pouce thick and tongued and grooved.

A boarded-in ceiling usually reflected a special circumstance - for example, to prevent cooking odours from rising from a kitchen into the apartments above; or to enhance the interiors of a chapel or meeting room.

Even more unusual was a plaster and lath ceiling (where in a large building as many as 35,000 cedar laths were a possibility).

Finally, there was the hazard of fire spreading through wooden floors and ceilings. No doubt this was a particular concern on Isle Royale as in France, and, in some rare cases, would have led to the laying of clay on floors.


Open ceilings on Isle Royale were popular. The exposed joists were finished simply and applied mouldings, if any, like the tringles above wooden partitions and walls, were probably carried around joists as required.


Topping a stack was usually a cap of some type. Cut stone caps were preferred, particularly by the military, who included their repair or replacement in general maintenance contracts; but bricks were cheaper and were perhaps chosen more often by private builders. Even wooden caps were a possibility.. Some stacks, too, had a protruding masonry string circling it somewhat below the cap.


The best mortar was a mixture of one-third lime and two-thirds sand. Properly prepared, which often was not the case, especially in its use in fortification works, it was a strong and lasting chimney mortar. A weaker, though frequent substitute, particularly outside Louisbourg itself, was a mortar that was clay-based.

Most chimneys were either of local rubble-stone or of New England imported brick. Some were also of local flat-stone. A few, generally in the countryside or on Isle Saint-Jean, were even of clay and straw, probably placed in a wooden frame. Well-cramped cut stone was also suggested from time to time.

Builders also constructed chimneys of local bricks, which enjoyed some popularity in the early years when there existed a kiln at Port Toulouse. Local bricks were a poor choice for exterior use, however, for their quality was exceedingly bad.

Local flat-stone was little better than local bricks particularly flat-stone which was too thin.

Chimneys of mixed materials existed as well. For example, one possibility was a chimney of stone and earth mortar from its foundation to above its attic floor. From that point the chimney continued upwards in a mixture of clay and straw (i.e. its stack wood framed and infilled with clay and straw).

Several Isle Royale proposals describe gypsum plaster chimneys in good detail, no doubt because the military held them in some regard. However, it is safe to say that none were actually built on the island. One view even held that gypsum deposits were not found commonly on Isle Royale, and that it was of an inferior quality and so would not stack properly in the kiln. Consequently, not only did it cost more, using local labour, to stack it than to burn it, but a third or more was lost when burned.

There were also chimneys that were temporary or primitive. A temporary barracks set up during construction project might a chimney of rubble-stone, bonded with a lime and sand mortar. Some tents even had chimneys. Among the most primitive chimneys, however, were those that fishermen or persons wintering in the countryside would have built of dry stone (perhaps with a clay mortar), and those that some former inhabitants of Isle Royale built on Saint Pierre and Miquelon after 1758. There, perhaps like on Isle Royale earlier, fireplaces were built without benefit of stone or bricks, with flues and chimney stacks of boards instead.


As a fire precaution some builders surfaced the entire exterior stack with a lime and sand mortar mixture known as a crépi.


Builders preferred a separate flue for each fireplace. The withes between the flues of the back-to-back fireplaces could be the thickness of one brick. The mason was to surface both the flues and the withes with a lime and sand enduit rendering.

Such flues were not excessively large on Isle Royale. A cantered flue might be 2 1/2 pieds long by 8 pouces wide with one pouce thick brick withes. For a 12 pieds high chimney with a back-to-back fireplace, brick flues 2 pieds 6 pouces wide by one pied 3 pouces deep were a possibility. Then again, a brick chimney, 17 pieds 6 pouces in height, servicing a single fireplace, might measure 3 pieds 2 pouces wide by one pied 6 pouces deep.


A firm base, a prerequisite of proper chimney and fireplace construction, was usually achieved by means of a foundation. One might be 2 pieds deep while another, of mortared rubble-stone could be 2 pieds 6 pouces deep, the same depth as the excavation itself. In the latter case both the foundation and the excavation could be 3 pieds wide.

An excavated foundation was not, however, the only means by which to achieve a firm base. Sometimes, instead, foundations were built immediately on the ground, or an oven/fireplace complex could rest on a raised foundation, one pied 4 pouces off the ground. There, in the latter case, the foundation base could be slightly larger than the main body of the oven/fireplace.

A firm base for both the walls of a building and its ground floor and first storey fireplaces could even consist of wooden piles driven into swampy land. In this case, Consequently, the bases of the building's fireplace could rest on 7 by 8 pouce wooden plates, placed across the heads of three rows of piles, each spaced 2 pieds apart.


The construction, maintenance and ownership of a shared chimney was not unlike that for a shared perimeter wall. Even the same type of legal entanglement sometimes developed as neighbours misinterpreted the Custom of Paris.


Chimney stacks and fireplaces were either freestanding or they were supported by or incorporated into a wall.

As a chimney stack rose builders would diminish its width - for example, beginning at 3 pieds wide but only 2 pieds wide for say the next 8 pieds 8 pouces of height.

Off-setting, the setting back of the stack at various levels of height, was one means by which to achieve this reduction. Thus, for example, a chimney might require one cubic toise of masonry for its foundation, 5 cubic pieds for its mantlepiece, but only 3 cubic pieds 4 pouces for up to its second off-set. One cubic pied more and the chimney was complete.

On the other hand, another stack might require only one off-set, and that stack rose 28 pieds above the fireplace.

It was a matter of good sense and some planning that ensured that a stack exited through a roof in the best possible location. A stack at a ridge was considered best; yet some stacks exited within the pitch of a roof. There, up against the stack, water could stand and accumulate beneath roofing slates.


Contracts for the maintenance of the roofs of king's buildings also directed that mortar be used for parging where a stack exited through a roof. In other cases, the parging was cement or gypsum plaster.

Lead for flashing around chimneys would have been superior to a mortar parging. Nonetheless, even maintenance contracts, which addressed the question of repairs to lead flashings elsewhere, such as the roof ridges and around dormers, did not specifically identify its use around chimneys. One, but perhaps not the only, factor for its absence as a flashing was possibly the high cost of lead relative to the mortar parging.


Common sense and the Custom of Paris dictated how much further a stack rose once it reached roof level. According to the Custom of Paris chimneys should be at least 3 pieds above the roof ridge. In practice, 2 to 3 pieds was common on Ile Royale. A practical distance for obtaining a good draw, this height also lessened the danger of sparks or of a chimney fire igniting a roof.


There existed the occasional chambranle or architrave, an expensive finish around a window or doorway opening. A casing, it was of a rather fine size, generally only one or l l/4 pouces thick, perhaps 4 pouces wide, of an expensive hardwood, oak or merisier, but sometimes of pine, and had a quarter round moulding between fillets. They were corner pegged. Their great expense was in the cost of the hardwood, the difficulty in working the wood, and in the resulting waste. Consequently, not every doorway in a house with them had them, nor were they always of hardwood (where pine was an alternate choice).


Charpente construction builders quite naturally framed their sills and lintels into the structural vertical members that comprised their walls. Window sills could be 3 1/2 pieds long and, depending on location, either 10 by 11 pouces or 12 pouces square in size. Some were elongated, extending beyond the vertical framing members, while others were apparently shouldered, to fit in between.

References to door sills are rare. A pine replacement sill, 4 pieds long, destined perhaps for a charpente building, measured 7 by 8 pouces in thickness.


Several masonry buildings had cut stone door jambs.

Wooden window and door jamb sizes varied from pine jambs of 6 by 6 pouces and 8 by 9 pouces for piquet buildings, to 6 x 7 and 7 by 8 pouce jambs for several masonry buildings. Both the lintel and door jambs of a cellar door could be 8 by 9 pouces, while the jambs and sill of the exterior yard door of an assumed charpente structure were 7 by 8 pouces.

Door and window jambs window might be of timber. Known variously as chassis, chassis dormant (in window construction, actually the frame which holds the sash), or cadre, timber jambs were to be set firmly in place with holdfasts (cloux à patte). The recommended procedure was for at least two nails to be driven through the shouldered tongue of the holdfast into the jamb.

Timber jambs of a separate nature were common, but not every builder used them. For example, while 7 by 8 pouce jambs were possible in one case, in another, a charpente bakery, with a 2 pouce thick hardwood door, the plan undoubtedly was to make use of the 10 by 10 pouce vertical pine members that defined the exterior door opening.

Not every building had wooden jambs, of course. Masonry jambs of cut stone, brick or flat-stone, rabbited as required and recessed to accommodate a window frame or door, were popular in masonry buildings.


On Isle Royale, door and window surrounds of rubble-stone structures could be of local rubble-stone; flat-stone or wood; or of local or imported cut stone or brick. Wood or flat-stone surrounds did not last in the harsh climate, however, and required constant repair after only a few seasons. Those of local brick deteriorated so quickly that no repairs at all were possible. But those of French cut stone proved their superiority almost immediately with their lower maintenance costs. Unfortunately, cut stone also required a high initial investment, and private builders, who did not usually have such levels of capital backing, were prudent in its use.

Only a properly cut, chiselled and roughened stone could be placed with the care demanded by cut stone. Bricks, on the other hand, needed only to be well baked to meet the standards of common practice. In either case, the recipe for mortar was one-third lime and two-thirds sand (screened for bricks, ordinary sand for flat-stone or rubble-stone).

In one instance, imitation mastic surrounds of cement and lime most likely were chosen. The imitation stones had the appearance of cut stone and were placed around at least 10 windows and a balcony door of an official's house.

The sills and lintels of masonry buildings were often of the same material as the surrounds. When of wood, these sills and lintels were sometimes made from planks, either of oak or of merisier, a local hardwood, or even of pine. Planed, tongued and grooved, the planks were often 2 to 3 pouces thick, with one known sill being 10 to 12 pouces wide.

A builder who used these hardwood planks within the bays of windows and doorways, to support the masonry above the openings, was employing a lintel technique the French referred to as palétrage. Elsewhere, the lintels were of pine timber (also found in palétrage constructions), ranging in size from 4 by 4 pouces and 6 by 8 pouces to 8 by 10 pouces; or were of cut stone, flat-stone, brick or once, at the hospital, even of hardwood, in the form of a relieving arch.

References to door sills are rare. In masonry constructions, the only described ones are of cut stone.


The difference between batten or emboîture was in how the carpenter set the horizontal members in place to hold the vertical tongued and grooved boards together. In batten construction he nailed either soft or hardwood boards, near the top and bottom, and occasionally another in between, set horizontally or diagonally. In emboîture, however, he assembled his doors, mortise and tenon style, with a hardwood board, perhaps 5 to 6 pouces wide, on each end, pegged in place.

The vertical boards of both types were usually of pine or fir, drawn from a common stock widely used for flooring and partition construction. Battens were generally also of softwood and so contracts often ignored a batten door in actual description since its price was no different than, say, an equal area of flooring. They discuss emboîture doors, however, because of the hardwood and the time-consuming joinery required, which made them relatively more expensive. The hardwood, as for the occasional batten too, was oak or merisier, both harvested locally.


Doors stood at nearly every doorway, trap or staircase opening. Of local manufacture, they were planed both sides, one or 2 pouces thick, one or 2-leafed, and were either batten or emboîture. Panelled and glass doors, both variations of the two basic doors, saw occasional use. Panelled doors, whether three or five panelled, single or 2-leaf, were the rarer type. Sometimes, half an interior panelled door might also be in glass.

For reasons of cost rather than for preference did a few owners choose a door entirely of hardwood. Economics being important it was perhaps more common to have solid softwood emboîture doors. One pouce thick, they might be entirely of pine.


Location and desired doorway width would pre-determine whether a door would be single or 2-leafed. Exterior doorways, particularly those for main house or storehouse entrance-ways, tended to be wide and so their doors were often 2-leafed. Within a house, however, doorways were smaller and doors were generally single-leafed. Exceptions were doors for corridors, oversize staircases and special rooms where a panelled 2-leaf door might opened out into another room.


Exterior doors were usually 2 pouces thick, but occasionally one pouce, whether they were single or 2-leafed or whether they swung inwards or outwards. In contrast, interior doors were generally just of the opposite size, with some l l/4 pouces thick. At times, too, the door which stood in an exterior opening was lined with a second layer of boards, or was even a storm door. Storm doors were perhaps unusual though because of the popularity of interior vestibules, and exterior storm porches.

An exterior glass door- one carried 28 panes in a frame - was also possible, as long as it did not compromise security, as for a boutique. Thus one might find one leading to a balcony or to a garden but not usually to a street. Otherwise, an owner would have installed a transom above an exterior door with normal size glass panes - one carried 20 6 by 8 pouce panes - set in a frame. Only a few, however, chose a transom for interior use.


A dormer, described as large could measure 2 pieds 9 pouces high by one pied 7 pouces wide. Smaller dormers might only be one pied 9 pouces by one pied 5 pouces. A simple dormer roof (and undoubtedly the cheeks too) might consume a square toise of wooden shingles; yet four large dormers could require the same amount of slate.


A dormer, as proposed for several military buildings with mansard roofs, consisted of two long side posts, a pediment, four smaller side posts, two wall plates, eight common rafters and a ridge beam. Boards, perhaps only 8 ligne thick laths, wooden shingles, and possibly shutters and glazed sashes, closed in each dormer. Timber sizes varied. Uprights, wall plates and ridge members might be 5 by 5 pouces.


Flashings varied too because lead was perhaps too expensive for private home-owners. They were more likely to choose a lime mortar (or perhaps even a gypsum plaster).


Builders placed their dormers wherever they required light, ventilation or viewing. Some situated them in line with the interior or exterior face of the perimeter wall; others placed them further up the roof slope. Some sat them directly on a wall plate; others below, severing the plate. A single row of dormers was common, and double rows occurred occasionally.


Dormers, if unglazed, required a frame or sash, either casement or double-hung. A sash, placed in a dormer above a staircase, presumably to light the way, measured 2 pieds high by one pied 6 pouces wide. Sashes with 18, 12, 6 or four 7 by 8 and 8 by 9 pouce panes were all possible.


Small gables dormers, with roof overhangs and glazed rectangular openings, occasionally with shutters, were popular on Isle Royale. Dormers other than the traditional type were rare. The chapel of the King's Bastion barracks had some lunettes and oval dormers, with eight 6 by 8 pouce glass panes in all. Dormers with roofs rounded, hipped, or shed-like, or with arched openings, were other possibilities.


Isle Royale fireplaces, though sometimes described as large or small, were not excessive in size. A brick fireplace that, for example, stood in a main room might measure only 4 pieds by 4 pieds to the mantle. Dimensions in fact varied throughout the town, ranging in widths from 3 pieds 4 pouces to 5 pieds, heights from 3 pieds 6 pouces to 3 pieds 8 pouces, and depths from one pied 6 pouces to 2 pieds 2 pouces.


Cast iron firebacks, which were rare and often limited to just one or two fireplaces even in a house that had them, were somewhat reflective of fireplace sizes. Some could have been 2 1/2 pieds wide by 2 pieds high, while others might have measured 2 3/4 pieds by 2 pieds 2 pouces high.

More popular than cast iron firebacks were iron bars. For example, a kitchen fireplace could require two bars and seven crampons. Or iron bars might be used everywhere but for a kitchen fireplace, where there a fireback made from 7 pieds of local cut stone was deemed more appropriate. Lining a fireplace with bricks was yet another technique for protecting a fireplace. Unfortunately, local bricks which were good for general purposes were too thin to last long in a fire.


Brick hearths were common and, although bonding patterns were unspecified, it is known that bricks were being set edgeways producing a hearth 4 pouces thick. The bonding material was again the standard mixture of lime and sand. Other materials were possible too - say, for example, a square paving stones set in plaster.


Builders did not attempt to have a fireplace in every room. Instead they were concerned with heating the main room only, and so most often chose a back-to-back fireplace configuration, with one such group to a stack. On the other hand, a one-over-one single fireplace configuration was popular where they wished to beat rooms one above the other, in two different storeys. Far less common, however was a one-over-one back-to-back fireplace configuration.

Sometimes a building had only single end wall fireplaces, with perhaps the same system in the rooms immediately above. In other cases, the masonry work of the fireplace stack could have sat outside the building. Here, using up an area 6 pieds 6 pouces by 2 pieds would not have been unreasonable.

An unusual fireplace arrangement would have been a back-to-back fireplace in whose side was set a third, smaller fireplace.


Home-owners of all building types preferred the rubble-stone fireplace. Finishing their jambs, mantles, breasts and stacks with a simple mortar rendering (often whitewashed) also kept costs to a minimum. Less frequently did they choose a fireplace of New England or poorer quality local bricks. Some also used local sandstone, though they suffered from the same fate as locally produced bricks: rapid deterioration in a fire.

Fireplace designs also included some of local flat-stone and some of local or imported cut stone. The body of a fireplace and chimney, for example, might be of flat rubble-stone. Its bonding mortar could then be the standard one-third lime, two-thirds sand mixture. Its jambs and, say, a three-piece mantle, however, might then be of local cut stone. Supporting the mantle, which in turn supported the rubble-stone breast, could be iron bars. Similar, iron bars were at times forked or arched - 4 pouces for example.

Fireplaces more highly decorated than the above were rare. Among the exceptions were imported cut stone cornices and plinths, or ones with surrounds of Quebec black marble. Generally though, fireplace surrounds, when of a more elaborate design, were of wood.- for example, oak or merisier planks, 10 to 12 pouces wide, 2 pouces thick reduced to 1/4 pouce of thickness for the wooden surround work of fireplaces. Mantles, say of 4 by 4 pouce pine members were also possible. Finally, wooden shelves were always popular.


Earthen floors appeared in some crude homes or storehouses. More sophisticated would have been a sand and gravel basement.


Pavé or stone floors appear under special circumstances. Even one double layered with a plank flooring on top was a possibility..

Street and building paves were similar: ordinary non-mortared rubble-stone laid on a gravel-like base. Using a rammer insured the proper slopes, with care taken to fill in the spaces between the rubble-stone with the same material as the base. Mortared rubble-stone and brick paves, at 3 1/2 and 5 1/2 times the cost of ordinary paving, were also available. Mentioned in early lists of prices, they are not described later, no doubt because they cost too much, or were not required.


Isle Royale builders preferred wooden floors. The common type was single layered, 2 pouces thick, tongues and grooved, of pine or fir and nailed down. Exceptions to the rule were often in an upper storey - the boards might be only one or 1 1/4 pouces thick or from Boston, of the least thickness - or, as in special place, of a hardwood, oak or merisier, 2 pouces thick, or, as in a heavily travelled but possibly temporary storm porch, of one pouce stock.

A finished floor was generally planed on the upper side only, even in a better homes. Some floors, though, were left rough; or on the ground floor they might be rough, but, above, in the upper storey, planed on both sides.

An alternative to the traditional floor was one comprised of butt-joint boards: in one case, the lower storey floor of rough boards and that above of planed boards which the owner had not nailed down. Others were more reminiscent of a one pouce bevelled roof sheathing than of a floor.

Double layered floors - of Boston boards in one case -were a possibility.. Squared, flattened-off or even split piquets also found use, particularly in cruder piquet structures. Another choices were common rafters, resting on sleepers and on a ground level nailer attached to one wall. The rafters probably butted.


The 18th century technique of sawing logs was parallel to the axis of the trunk and so the boards produced were of varying widths. Probably, then, a builder laid a floor in panels of boards of equal lengths rather than equal widths. Each board, however, even in floors where they only butted, was to have its edges free of bark. The process, known as deligne, was a second cut along the edge, perpendicular to the face, to produce a parallel square edge. A process often specified in military contracts, this concern with detail might suggest that not all floors were laid with such care for the type of boards purchased.

Ideally too, a floor would lie in place for eight to 10 months prior to final nailing, two nails to a joist. If that floor were of hardwood, a carpenter would also have pre-drilled his holes so as not to split the planks or joists when nailing them down. Iron pegs rather than nails were also a possibility, as were wooden pegs, for such places as powder magazines where sparks could cause a fire.


Far better than sleepers though, and quite easily achieved in charpente and masonry constructions, was the elevation of floor joists above the ground. One method, in charpente construction, was to dovetail (or tenon, though a tenon might break) a joist into the frame. Another was to rest the joists on a ledge, making use of the foundation (and, at the same time creating a ventilated crawl space).

A ledge was not, however, every builder's preference, even when one was available. Neither was an open crawl space and, indeed, one contract stipulating a 2 1/2 pieds high foundation, specifically directed that the crawl space be filled in level to the wooden ground floor above.

Large wooden beams sealed in a masonry wall, thereby weakening the wall, was another way to support joists. Critics of the time ridiculed this method and suggested alternate techniques: stone ledges at each storey of a masonry structure; or 6 pouce deep joist sockets into which joists could be thrust, sealed in mortar and secured by nailing on both sides or supporting with one pouce thick iron S-hooks; or wall plates at the summit of walls for carrying joists and roofing members. Iron stirrups and flat iron bands were also useful devices for securing joists.

Joists which normally span a building's shortest distance, usually the width, sometimes required mid-support for safety's sake. Such a situation usually arose in masonry buildings which tended to be on the wide side. The traditional solution was a mur de refens, an interior bearing wall that might also support roofing members, or, if of masonry, a chimney stack.

Anyone expecting the weight of a floor to exceed normal limits would have chosen shoring, a proven technique for added joist support. As one method carpenters might have fashioned large piquets or oak propos to support a floor. In general, props were simply nailed at each joist with large nails.


The finish on joists varied. They were either carefully hand-hewn with well-defined, sharp edges, or they were further planed and given softer edges, like a quarter-round moulding. Otherwise they might be far more roughly hewn, if destined for a relatively crude construction, or half-squared off, or simply split from the log.


Joists were large by today's standards. Seven by 8 and 8 by 9 pouces were common, except in less travelled areas like attics, where sizes were about one-half the above. Their overall size, with their depth being the greater dimension, encouraged wider spacing between joists than practiced today. A distance of 3 pieds, the one most often mentioned, was perhaps routine.


A sleeper - a joist which rested directly on levelled ground - was susceptible to rot. A precaution might have been to placing charcoal clinkers (gravel could be used as well) between each sleeper. The idea was that the charcoal rather than the wood would absorb most of the moisture.


Building contracts frequently stressed the importance of achieving a solid base. Success depended on several factors: the building site, the type of construction, and the care taken during the building stage. Proper site development varied from clearing trees, removing imbedded or scattered boulders, draining or filling in insect-infested swamps, or adapting to loose beach material.


The foundation of a charpente building, a superior technique for controlling the decay of wood because it elevated wooden members above ground level, was of masonry, usually rubble-stone with a long-lasting mortar bond. Foundations could be of any height, rarely even of one-half storey high, more likely they were only 2 1/2 pieds high. Some were even below grade level and others only sufficiently high enough to produce a raised basement or cellar.

A masonry foundation was not only good preventative maintenance, protecting main perimeter sills, flooring joists and even the corridor sills of building from rot, but it was also vital to the proper transfer of a charpente building's charge into the ground. Thus, to achieve a solid base, un bon fond as the contracts described it, some, though not all designs utilized separate and distinct footings beneath the foundations. Other builders, however, likely achieved the same result by first dropping the largest stones into the trench.

Known foundation thicknesses ranged from one to 3 pieds. Rubble-stone was the most popular masonry material, but other available stone materials, though never directly specified, were brick and flat-stone. Just west of Block 1 the builder of the Lartigue house chose a faced stone, while another, at Block 20G, opted for an unspecified decorative material.

It was unusual to find a charpente building on Isle Royale with a foundation other than masonry. However, piquet piles, post and planks and dry masonry were perhaps alternate approaches. If it were piles, driven into a drained, swampy area, then the carpenter would have mortised and pegged to the top of these piles or solage, the sills upon which the building was to sit.

A charpente building without a foundation was another possibility. Small constructions like latrines were prime candidates, and even larger buildings were a possibility.


In rubble-stone masonry constructions without basements, a builder often excavated a 2 1/2 to 3 pieds deep by 3 pieds wide trench in which to build a 2 1/2 pieds wide footing as support for a 2 pieds wide perimeter wall. Dimensions varied, of course, depending on the site, a building's downward charge and on the builder's requirements: Some foundations were 2 pieds wide with their supporting walls being only 1 l/2 pieds thick; Others were 3 pieds, that is, as wide as the excavation ditch itself, but they supported walls only 2 pieds thick. If a powder magazine, then foundations of the gable ends might have been less thick than those of the long sides.

For a masonry structure with a basement, one would excavate completely down to basement level and might raise the rubble-stone walls between two guidelines (against the earthen limits was another possibility). Then the main walls or murs de face, which were to rise off this bon fondement, might be 2 pieds thick throughout, from top to bottom. Another option involved simply hollowing a basement out of the ground after the house was constructed.

The foundations and walls could be of a uniform thickness of, say, one pied 6 pouces. By way of contrast, other builders used a footing-foundation technique to achieve a stable base. In addition, the principal walls could be built in the middle of the footings, leaving a ledge to either side. Builders could have benefited from interior ledges as a matter of principle, using them to support their flooring joists, but not all builders did, some instead constructing their walls to the inside edge.

As a result of Isle Royale's destructive frost/thaw cycle, the movement and uneven settling of walls and resulting high maintenance costs produced a focus on well-constructed foundations. Of particular concern was the expansion caused by freezing. The solution: well cramped cut stone quoins, door and window surrounds, and a cut stone footing-foundation (socle) that rose at least 2 pieds above ground level.

A masonry footing or foundation sometimes required additional support to achieve a firm basis. Two possible options were as follows: A builder could place beneath the masonry foundation a wooden grillwork, of reinforced iron-tipped pointed piles, no greater than 12 pieds long and no smaller in circumference than 9 to 12 pouces at the small end; or, instead of the grillwork, he could substitute boards, perhaps 18 pouces wide and 3 pouces thick.


A foundation was not a requirement to piquet construction, but a solid base was no less important there than in a building type like charpente that had an underpinning. In piquet construction, a trench, 18 pouces to 2 pieds deep (then back-filled), was the anchor since walls were buried directly in the ground. If the land, as with a swamp, were not suitable for digging, then perhaps a builder would have driven his piquets, as for the support piles of a charpente house .

Ground level decay, inevitable in this type of piquet construction, perhaps persuaded some builders, familiar with military palisade and fencing techniques, to have first charred the ends of the piquets before planting them, or, as with boundary markers, to have set pieces of coal beneath their ends, or, using common sense, to have placed root ends up rather than down in the ground. Others, of a more fundamental bent, however, practiced a more traditional approach - of raising walls out of the ground.

This method entailed wooden underpinnings not unlike sleepers (joists), but employed words like solage, solle, or soller that were reminiscent of the nomenclature of charpente construction - even though foundations there were usually, though not always, of masonry. As an alternate piquet technique, such buildings had underlying support systems that raised the piquet walls out of direct contact with the ground. In such cases builders would have placed a set of spaced members on or in the ground, with a second set on top running perpendicular to the first, so that these wooden solages rather than the walls proper would have begun to rot first. Nevertheless, over time, rot would still have spread to the walls, as the solages absorbed and transferred moisture.


The popular fill in charpente construction was vertical piquets, palisades or posts, round or squared-off, some perhaps as large as 12 by 12 pouces, caulked with the same materials as in piquet construction. This vertical fill was also perhaps easy to remove, possibly for repair or replacement.

Masonry fills, though frequently of rubble-stone, stone, brick, or some combination of the three, were generally of wood, and required a large frame to support their weights. In fact, the frame of a charpente building with a wooden fill was generally large enough to have supported the added weight of a masonry fill.

It was rare that a charpente building had no fill at all, with, say, a board finish inside and out. and a dead air space in between.


Caulking, the method by which builders closed off the vertical joints of piquet structures, consisted of non-mortar materials, such as moss, clay and straw, or clay alone, known generically as a bousillage, which, early-on, were the dominant infills,. Later-on, lime-based caulkings were preferred. The durability of mortar caulkings simply outweighed the added expense relative to natural materials. A few builders, perhaps those who used the tighter fitting squared-off piquet, may have dispensed with a caulking altogether, but others, with a lime-based mortar caulking, might have felt it prudent to protect their investments, and so applied a lime and sand mortar finish on both the interiors and exteriors of their buildings.


Ladders, even rather steep ones, instead of stairs, to basements and attics were quite common. They ranged in size and materials: for example, of 6 by 7 pouce pine members, or even of four rafters.

Also popular were roof ladders. A fire precaution, they were permanently secured at the ridge by two iron clamps, with a shorter ladder propped against a wall providing access. In particular, roof ladders were probably of oak.


A potager was essentially a low rectangular masonry structure, perhaps 4 to 5 pieds long by 2 1/2 to 3 pieds wide, whose top surface featured two or three round or oblong holes, into which metal heating stands with pull-rings were placed. The masonry was either rubble-stone or brick, bonded with a lime and sand mortar. Flat and/or bar iron and iron relieving arches helped in the support of the masonry.

A potager had no flue of its own to vent toxic fumes, and so required the use of either a fireplace hood or a nearby window. Poor circulation and rising fumes might also provide the reason for installing ceiling boards above a potager.


Kitchen fireplace construction sometimes included bake ovens and/or potagers for keeping food warm. They were built only in a few of Isle Royale's better homes, however.

Ovens were built on occasion within and at the rear of fireplaces. Ovens also appeared in the sides of fireplaces or were independent of them but still under their hoods. Some were also not of original construction, having been added at a later date within an existing fireplace.

An oven could be half rubble-stone and half brick, and, like other ovens in the town, would have required iron relieving arches as well as doors.


Bearing partitions were more common to masonry structures than to those of wood which generally were not as wide. Such partitions occurred whenever a builder needed to transfer stress. If he raised them in masonry he often finished them like the main walls.

Some masonry bearing partitions ran the length of a building with similar ones set across its width, not only to handle stress but also to create rooms. In contrast. others would have divided a building into two separate residences, but would not have created individual rooms. Non-bearing plank partitions served that function instead.

A bearing partition of piquet or charpente was always a possibility.. In one case the framed members measured 8 by 8 pouces, perhaps the same size as those of the perimeter charpente walls. Several masonry structures had framed wooden partitions as well, one even being described as a separation de colombage.


The common partitions were non-bearing, consisting only of vertical boards. The boards were planed on both sides, tongued and grooved and fastened to the floor and ceiling with nails and a wooden tringle, a simple moulding perhaps only one-half to one pouce high. Such partitions could be easily moved when necessary, as was often the case.

Both one and 2 pouce partitions were assembled in the same house for no apparent difference of reason. Likewise, the degree to which partitions were finished could vary within the same building - for example, a mix of planed and un-planed partitions; or a mix of planed on one side only and not at all.

Other types of non-bearing partitions consisted of Boston boards with bevelled joints, boards with butt joints, a combination of panelled boards below and trellis work above, a brick wall built as a security precaution, and the ever popular piquet partition (second in use to the common board partition). Piquet partitions also often co-existed with board partitions in the same house.

Piquet partitions were built from small, split, hewn, re-sawn or round piquets. Those in a piquet buildings might be no different than the outer perimeter walls: made from logs set vertically in the ground with a caulking of clay. Even a fine residence could have several partitions, though plastered with gypsum, either on one side only, or on both sides was an alternate choice to clay. Gypsum, as a rendering however, was more expensive than line and sand, which would have been more frequently used.


Builders would have preferred to flash with sheet lead but lead was extremely expensive. Consequently, they probably more often caulked ridges and valleys with mortar or plaster, particularly since these were the usual materials for flashing chimney stacks and dormers.


Finally, a few roofs had gutters, most likely inexpensive wooden gutters, such as of 4 by 4 pouce timber. some having been placed to satisfy the terms of the Custom of Paris, others for more practical rather than legal requirements. More expensive gutters, like of lead, would not have been popular with private builders however.


The Custom of Paris, Isle Royale's civil code, could also colour design on occasion. A builder, wishing to place an attic window in an end wall, for example, could always do so by raising a gabled roof, but if the wall straddled a property line, he would have to adhere to Articles 199-202 of the Custom - articles which could restrict the window to a precise location while adding to its cost. Otherwise, he could reach an agreement with his neighbour to waive these building restrictions, not place a window at all, or raise a hipped roof with a dormer instead.

A dormer, unlike a window, did not usually provide a view within the meaning of Articles 199-202, since it did not normally allow a person "to look perpendicularly into the home of a neighbour." Unfortunately, a hipped roof created a problem which a gable avoided: it caused water to flow, and if that flow were upon a neighbour's property or building, a legal entanglement was always a possibility. On Isle Royale, as in France, roof gutters were a solution; the neighbour waiving his rights, either in writing or verbally, was another solution; or the builder might decide against a hip roof, and look to another design instead.


The design of a roof, usually hipped or gabled, depended upon personal preference, price, aesthetics or tradition. A mansard style roof was rare. The only other known roof structures of Isle Royale were the shed, the flat and the pyramid types. They were generally associated with secondary buildings, such as lean-to's and latrines.

Roof structures of Isle Royale, whether hipped or gabled, with either tied rafters, trussed rafters, or a trussed system of purlins carrying rafters, represented the range of choices builders had from the most simple system, being the use of common rafters only, to the most complex, being the truss. Typically, a truss consisted of one king post, two principal rafters, one collar beam, and two braces. In addition, there could be a cross beam running from one wall to another to replace or join a collar beam, or other secondary bracing and purlins in support of the roof.

Roof structures on Isle Royale were not unlike those of other towns of Europe and North America. Yet they were typically French. They usually had ridge beams, king posts and flared eaves, produced by a timber, generally 3 pieds long, attached to the ends of the rafters, to throw water clear of the walls.

The ridge beam was usually bevelled on top and on two sides to allow the other members to fit cleanly, usually passing over the king post. On occasion, however, it was framed into the king post instead. Ridge beams were not mandatory, however, and there were some exceptions.

Builders wishing to transfer the weight of a roof to a perimeter wall generally, though not always, used a wooden plate, either single or double, between the wall - be it masonry, charpente or piquet - and the roof members. Walls of masonry structures were usually of sufficient width to require not only a double plate but also blockers in some cases, placed in the empty cavity that could result between plates.

Interior bearing walls appear not to have been common on Isle Royale, but were sometimes required to aid perimeter walls in support of a roof structure. One proposal stressed that the number of interior walls depended on the number of roof trusses, thereby sustaining the ridge beam, and the purlins at 6 pieds intervals.

Roofing members were often on the large side and, being timberwork, were usually hand-hewn rather than sawn. However. sawn members were used, particularly in less refined structures, two boards, for example, comprising the ridge of at least one inexpensive building. In some piquet buildings, half-squared off members and in the round (poles) were even tried. Piquet trusses and rafters were also fairly common.

Roof timbers - pine or red pine of Isle Saint Jean are mentioned - varied in size according to use: the smallest being 3 by 3 pouces for the accoyeau of a flared eave, to 11 by 12 pouces for a hip rafter. In between there was a large variety of sizes that were used.


The demand for stripped logs for piquet constructions and the stripping of live trees in the surrounding forest provided an inexpensive source of supply of bark as a roofing material. Damage was so rapid and pervasive in the latter case, however, that in 1717 an ordinance was issued forbidding outright the practice of live stripping and the use of bark as a roofing material.


Board roofs, second to only shingled roofs in popularity, were poorly described. What is known is that those of Isle Royale were laid either in single or double layers placed horizontally or vertically to the eaves with butt, with board (spaced apart in one example) and batten, or with overlapping (clapboard style) joints as required or desired. Boston boards and thicknesses of one pouce or 1 1/4 pouces were acceptable.

Boards next to another material on the roof of the same building were not unknown.


There were six major roofing materials in Isle Royale: bark, wood, slabs, sod, shingles, slate and boards. Slate, however, was not used during the early years of the settlement.


The rising number of building starts might also explain the source and popularity of plans de bois, or wooden roof slabs, flat on one side and curved on the other, with the bark still attached. Builders choosing to square off their piquet logs (rather than using them in the round) were an obvious source. Another were sawyers and hewers of timber who would have produced a similar by-product.

Plans de terre, or slabs of sod with grass and plants attached, were generally reserved for the roofs of crude buildings. Their use was never widespread. Then, in 1717, the year that Louisbourg was chosen capital of Isle Royale, the king, having banned bark roofs entirely from the town, implicitly included sod and plan de bois in the ban too. Bark, sod, and wooden slab roofs were costly maintenance headaches and fire hazards, and accordingly boards and shingles were to be used for roofs until slate became readily available.

The technique of laying a bark or plan roof was little discussed. Wooden slabs were the base material for one sod roof; bark the base for another.


The bevelled roofing board travelled the same evolutionary course, from Newfoundland to Isle Royale, as did the bevelled weatherboard. There, at Plaisance, prior to the 1713 settling of Isle Royale, builders who were versed in the traditional use of laths had already begun to experiment with board sheathings and shingle coverings. This development was out of necessity as neither slate nor tile could hold in the wind.

On Isle Royale, the military, though committed to the use of slate, often chose shingles because of a problem in the supply of slate. But in those early years neither slate nor shingles were effective against driven water and powdered snow, and the elements were easily penetrating buildings through the spaced laths to which the slate or shingles were nailed. As early as 1716 then, several proposals were put forth for one pouce thick roofing board (of a type also suitable for floors and partitions) in place of laths. Undaunted, however, royal officials continued to use laths for some time.

Finally, in the 1730s, the bevelled roof board made its appearance. Always one pouce thick, in every other way it met the same specifications of the bevelled weatherboard. A 1738 memoir also clarified its function: bevelled roof boards were a second line of defence against the elements. A tight fit was critical, uniform bevelling a necessity. Bevelled boards thus probably assured the continued use of slate on King's buildings, slate being particularly vulnerable to the climate of Isle Royale.


Wooden shingles eventually displaced both bark and plan materials, becoming the most popular roofing choice. The memoir of 1717 merely confirmed that trend. Shingles already cost one-quarter less than bark as a roofing material and a supply was readily available, first from local splitters working during the autumn and winter, then from New England merchants. By 1751 the New England shingle was totally dominant, having displaced the local product completely (excepting, of course, in time of war).

Several factors clouded the question whether there was a standardized approach to shingling on Isle Royale. Sources of supply were quite varied, though the New England shingle did dominate, and proposals that never advanced beyond the planning stage were numerous. Yet there were some common characteristics in all the descriptions: shingles were tapered with a reduced thickness from butt to head, they were placed in equal rows with the length of each shingle exposed no more than one-third, and, beginning in the 1730s they were nailed to a bevelled board sheathing. The New England shingle, in particular, was pine, 18 pouces long, 4-5 pouces wide and 4 ligne thick, and nailed with two nails to a shingle. Other shingles varied in description: of oak or white fir, supplied in lengths of anywhere from 12 to 14 pouces; in widths ranging from 5-6 pouces to 9-10 pouces; with a butt of one pouce and a head of one ligne; and nailed either with three nails to oak laths of 4 pieds long, 3 pouces wide, 6 ligne thick, or to Boston boards that were nailed in turn with two nails to each rafter.


Local slate, discovered two leagues from Port Toulouse in 1716, was of inferior quality and so builders, forced to use imported slate from France, looked towards Nantes, Angers and, in particular, to St. Malo, whose slate was considered to be the best. Roofing slates arrived on Isle Royale in pre-cut assorted widths of proportional lengths, in cases each containing from five to six hundred slates. An acceptable range of widths was 5-8 pouces (under 5 pouces was once declared unacceptable), although, inexplicably, a slate in the range of 5-7 pouces (with lengths proportional), described in a 1745 order for 26,000 slates, was thought to be large. A slate was dressed on three faces and nailed to the sheathing with two or three flat-headed nails, allowing for an average gauge of 3 1/2 to 4 pouces left exposed to the weather.


The construction details of a batten or emboîture shutter were very similar to those of a door. Two pouce thicknesses were unlikely, however, although 1 1/4 pouces was an alternative to the common one pouce thick shutter.

Shutters generally either equalled or were slightly larger than the window itself. Occasionally, though, their dimensions were given as less than the size of the sash; in other examples, their width might be the same, but their height was greater than the sash.


Shutters were popular for a variety of reasons: a desire for privacy or security, a need to shut out the elements, or a concern for protecting the glass. But shutters were neither mandatory nor always found on the exterior, though most were placed there. A street-facing boutique, a yard-side room and two smaller rooms on the ground floor of a building had exterior shutters but the two street-side rooms and a yard-side kitchen did not. In contrast another residence made use of interior shutters, but on the ground floor only, and only within the storehouse section. The windows were also barred, although not glazed.

Owners were also to place shutters on occasion in upper storeys, including those with dormers. They found them particularly useful when leaving their dormers unglazed. Shutters, though, did not have to shut out the outside completely to be effective. Some were pierced with an opening, or perhaps even had a window pane or two.

Finally, a glass door, here or there, may have been shuttered, as would the occasional shutter have been of the venetian type.


Hardwood stringers, treads and risers required the same day, tongued and grooved oak or merisier planks as for floors, and were usually 2 pouces thick. Stringers, which were to be planed and finished with a quarter round moulding, were at times 3 or more pouces thick, however. A staircase with 2 pouce thick hardwood treads and risers, and 3 pouce thick hardwood stringers was a possibility.

A hardwood staircase might have used 2 pouce thick merisier planks, for treads that were 10 pouces deep, stringers which were 10-12 pouces high and balustrade 4 pouces wide. Post and newel pieces could have been 6 pouces wide.

A hardwood plank newel post could have been 10 pouces wide. Risers could also in height throughout the same building, from 4 pouces 6 lignes through 6 pouces to 8 pouces for attic stairs.

While all the treads and risers of a stairway of one house night be of hardwood, in another house, only the first step of that material, with all the remaining of Boston planks, an imported softwood. Treads of pine planks, 2 pouces thick, 3 pieds wide were always a possibility.

The planks for a softwood staircase originated from the same stock reserved for common flooring: planks of pine (or fir), 2 pouces thick, planed one side, tongued and grooved. Ten and 11 pouce high stringers were perhaps common. Likely exceptional in staircase design was the use of planks planed both sides, normally intended for partitions, as well as the use of one pouce thick fir planks for risers, or the use of 3 pouce thick pine planks for stringers.


Military and privately built staircases were similar in materials and techniques, and in design, whether winding, horseshoe-shaped or in a straight run. Accordingly, a hardwood staircase, of three winders only and an upper landing, was a possibility.


Stairway width varied. Hardwood treads and risers which were 2 pieds 9 pouces wide were a possibility. In another case, the treads of a small pine staircase were 3 pieds wide, but they were 4 pieds wide for a larger pine staircase. Four pieds was another possible width.

Pine might be the choice for a 4 or 6 pouce square newel post. Pine sole plates and cross pieces might then be 4 by 5 pouces, or in other cases, 3 by 4 pouces thick. A larger staircase could have a newel post measuring 6 pouces square. Where a pine post and its banister were 5 pouces square, the large posts, sole plates and cross pieces of the pine staircase might be 6 by 7 pouces.

Sawn balusters, 4 pouces in width, might be curved and mortised and tenoned securely in place, 4 pouces apart.


Builders preferred hardwood for stair construction, yet many would have chosen softwood. Even the timberwork, if there was any, should be hardwood, declared one set of military specifications. Mitigating against hardwood for general use, however, was its high cost and the protracted time it took to work to proper form.

Pine was the practical, if not the only choice of most builders; oak, merisier and white fir were highly regarded however.


The second major building type, charpente, or half-timber, its frame a network of connected horizontal and vertical members, was superior to the piquet system in structural design. Half-timbering, which allowed craftsmen working with joinery, often mortises and tenons, rather than nails, to use wood to its greatest advantage, was a system that balanced or counterpoised competing forces in a tied frame that absorbed and transferred weight and stress. Pegs for the joinery, more an afterthought than a structural necessity, nevertheless helped the frame cope with unexpected strains that sometimes developed.

The hand-hewn, squared-off members, used in charpente constructions, were thick, often more than a foot, and were large even to piquet's standards. Assembling such timbers called for practiced workmanship, to ensure that the parts of the frame - the horizontal wall plates and ground sills, the widely spaced corner and intermediate posts, and the diagonal posts - fitted together as planned.

There were several techniques: intermediate posts tenoned into the plates and sills, ground sills and wall plates into the corner posts, intermediate posts (excepting the diagonal ones) severing ground sills, even the omission of ground sills beneath some windows. Procedures for the same technique, a ground sill tenoned into a corner post for example, varied too: one builder might sink the corner post into the foundation while another might place it directly on top of the foundation.

Finally, in charpente construction, there were the other members that stiffened the frame: headers, sills, joists, the occasional framing members high in a gabled end, and the diagonal wind braces that tied the plate to the corner post.


French builders, who normally used the term charpente to mean a half-timber structure, also used the word colombage on occasion. They usually, though not exclusively, employed the term when referring to the prefabricated half-timber buildings that the English occupation forces had brought to Louisbourg between 1745 and 1748. Upon their return, the French found three of these buildings unfinished, their fills en colombages missing in both the upper and lower storeys. At other times, they used the two terms, colombage and charpente indiscriminatingly, when describing the same building, even those of their own manufacture, with either masonry or wooden fills.


Rubble-stone masonry with its expensive and labour intensive load-bearing stone walls, was the least common of the major construction types on Isle Royale. The royal authorities built the majority, but few private individuals, wishing to enjoy the inherent qualities of strength and beauty which stone buildings appeared to exude, could afford the high initial construction costs.

Local government propaganda openly encouraged private masonry construction. But private builders took a more cautious approach, noting the slippage and warpage in the fortified works, the nature of local rubble-stone generally too round or too small, and the required level of workmanship necessary for a building strong, plumb, level and on a firm base. Lime mortar needed to be well mixed and sieved, one-third lime and two-thirds granulated sand; the sand, being sea sand, needed be exposed to a rain/snow cycle to leach out the harmful salts; the stones, being quite irregular at Louisbourg, needed be first shaped with sledge hammers; and the raising of walls needed be a course at a time, allowing the mortar of one course to dry before raising the course above.

A completed wall, some perhaps strengthened with iron reinforcing rods, was as thin as one pied, and as thick as 3 pieds. Quite common though was the 2 pied thick building wall, its largest stones at the bottom, rising up with many long headers, to a summit whose dimensions might be less than below. This reduction might have been achieved in several ways: either by setting back the wall at each floor level, or by introducing a natural inward slope: 2 pieds thick at the bottom but only one pied 8 pouces at the top.

Alternating stretches and headers, of brick or cut stone for example, strengthened the corners of masonry buildings, added to the cost, sometimes substantially, of a building when of a material different than the main walls, and were a fashionable aesthetic touch for an owner wishing to impress a neighbour or an entire town. The cut stone quoin, particularly when used with cramps, to counter frost heave, was the superior quoin. Brick quoins was an alternative choice.

Imported brick from New England (which early on displaced the inferior local brick of the pre-1745 siege period) measured only 7 pouces long by 3 pouces 6 lignes wide, by one pouce 8 lignes thick, and was smaller than that of Isle Royale: 8 pouces 3 lignes by 4 pouces 2 lignes by 2 pouces 1/2 ligne. In construction, for chimneys and ovens for example, its mortar recipe was the same fine mortar as required for rubble-stone constructions.


Migrant and less well-to-do fishermen who required a building erected on a jetty or fish stage jutting into a harbour often put up simple sheds, with light roofs and walls of conifer branches, set on equally flimsy stages. Other more sedentary fishermen may have built more substantial structures, perhaps like those depicted in several harbour views, apparently with sod roofs and walls.

Another type of light construction were the board buildings raised as temporary shelters for construction workers. Easy to erect and remove upon completion of a project, they were relatively inexpensive in materials and labour. Here the boards might be as thin as one pouce thick, required nail in their construction, and fitted with doors that locked.

Open air shelters were another possibility. To cover an exterior oven, one might utilize a charpente structure, with its shingled roofed shed-like, with open walls of framed posts and cross-pieces. For a market place, one might place spaced vertical poles set checkerboard fashion.

Another building type might consist of exterior walls made-up of 2 x 3 pieds thick spaced masonry pillars, each perhaps 7 pieds high. Across their tops stretched a wooden wall plate and in between the pillars, framed and open partitions serving as a partial infill. Beneath the floors, its sleepers could rest on a 3 l/2 pieds thick layer of back fill secured from the initial surface excavation for the building.

Structures with a small 2 pieds high foundation walls supporting 8 pieds high wooden posts were other possibility. Between each post and the foundation was to be a small square of masonry; the roof was to be shingled.


The few Isle Royale builders who chose the pièce-sur-pièce building type have left a poor record. In one case they were described as having vertical corner and intermediate posts, grooved top to bottom, placed 10 pieds apart, between which would be dropped the horizontal posts that built up the walls. In another instance, a pièce-sur pièce à machicoulis tower was to be constructed of one pied square horizontal members, with dovetail joints at each of the corners and mortises and tenons at each of the large or intermediate posts. The finish of the horizontal charpente members in the upper storey of this charpente tower was to have been on all four sides - but of all other members, on three sides only.

A common belief was that pièce-sur-pièce structures might last 40 to 50 years.


Piquet, brought to Isle Royale from Newfoundland in 1713 by the original colonists, was a wooden wall construction technique. Not the dominant type after 1721, as in the first eight years, it remained popular until the final siege of 1758. Such buildings were both quick to erect and usually inexpensive.

Piquet walls required logs 9-10 pieds long, round or squared-off. Builders stood them vertically, close together and without a foundation, instead staking the logs directly in the ground. These walls were then stiffened, in one or two places: across the wall, near the tops of the piquets, with a length of wooden rail or ribbon nailed to the wall; or on top of the wall with a length of mortised wall plate fitted over tenons on the ends of the piquets.

Builders, wishing even more rigid walls, added arch boutants, accords or contebouts, wooden struts that they jammed up against an exterior plate, which, in turn, were attached to the wall plate. Such a procedure was less possible in those urban settings which issued building regulations that forbade similar like projections, struts for fences, from advancing too far into a street. As an option were interior corner bracings, diagonal wind braces in the walls or even a dependence upon floor and ceiling joists to keep walls rigid.

Piquet structures, their walls solid, without famed openings and rarely built with a wooden solle or sill (buried in the ground) - even those with wall plates - were not framed constructions in the traditional sense. Moreover, they appeared not to have distinct corner posts, discernible in function from the other piquets, suggesting that builders probably raised such walls a single piquet, a larger section or entire wall at a time.

Walls during initial construction consequently much resembled piquet or palisade fences in type of wood chosen and in the techniques employed. Fence specifications, recognizing a supply problem, had quickly substituted fir, spruce and pine in place of oak. Piquets for posts were to be straight, 9 pieds long, 6 pouces in diameter, with a ribbon 4 pouces wide, 2 pouces thick, embedded one pouce deep into the piquets, near the top. A single 6 pouce spike, driven through the ribbon at each post - alternatively, one spike at the top of the ribbon, the next at the bottom - made the fence rigid.

A common belief was that piquet structures, with walls planted in the ground, would last 12 to 15 years. In fact, they often lasted much longer.


Shared constructions along property lines for party walls and fireplaces was a common technique. The Custom of Paris, a written common law, was the controlling regulatory reference for all exigencies, including the sharing of initial construction costs, future repairs and alterations. Neighbours, however, could mutually choose to ignore the Custom and agree to alternate approaches, both verbally and in writing, but at their peril if by word alone. Therefore, common walls might produce attractive savings, but they could also result in expensive legal entanglements for those not properly versed in the law. The Custom, whose principles were both basic and few, was itself not complicated, but in complex constructions, builder, neighbour or new owner might not always agree in their interpretations of the law. Indeed, in France, a large body of jurisprudence grew up around the Custom for guidance.


The Isle Royale climate could be harsh and varied: temperature, while moderate compared to the Canadian interior, would fluctuate widely, producing destructive frost/thaw cycles; cold summer fogs moving in routinely from the sea would mean that dampness would never entirely disappear; and winter gales springing up suddenly would drive rain, snow, sleet, ice or spray against buildings built on the edge of the Atlantic Ocean. Building damage mounted yearly and repairs were excessive. Some traditional protections failed and new ones were tried in a frantic attempt to save investments, and the technology quickly changed.


Exterior painting was always a possibility, but in reality a lack of sustained military or civilian commitment to the idea and a continued problem with supply meant that painting was not general practice. Notwithstanding, the military wanted to paint all its exposed wood, a deep red - for reasons of protection rather than aesthetics - all doors, shutter, window frames, gates, railings, sentry boxes, gun carriages, even iron cannons, but this plea was not made until 1739. By then the problem with rot was critical. In conclusion: exterior painting was not generally practiced on Isle Royale. Even private building contracts, even those sufficiently detailed to provide precise details on the size of bevels for the weatherboards, did not include any rider concerning exterior painting.


The common protection in the early years, the covering of an exterior surface like a wall or chimney, first with an earth-based or a lime-mortar-based finish, followed perhaps by a lime-wash (whitewash), or perhaps even paint, took two forms: crépi or crépissage, the rough coat applied either as a preliminary or as a final covering; or enduit, a crépi more expensively refined through a screen, to produce a final, fine, uniform finish less apt to crack, and technically, though not always, trowelled over a crépi.

Local clay, suitable and inexpensive as an earth-based finish, by itself would have demanded constant attention since it lacked staying power, and so a builder sometimes combined it with lime. This combination was only a slight improvement, and a rendering based solely on lime proved to be more popular. The common recipe was one part lime to two parts sand, but did not include directions regarding thickness or precisely how much of a wall to cover.

Local kilns provided a relatively inexpensive source for the lime. Gypsum, found in great quantities on the island, was also the base for some renderings. An enduit en plâtre, however, was rare and specifications reserved its use to inside work alone.

Building views also suggest the sparing use of renderings on piquet structures, revealing visible joints and the occasional rounded piquet. Had these owners used only enough of a crépi to cover the caulkings alone? In contrast, views of charpente buildings, certainly some with piquet infilling, illustrate structures with exposed framing members but with hidden fills.

With laths, it was possible to maximize the degree to which a wall might be covered. A common practice may have been to nail small exterior laths (to which later was applied an enduit of lime and sand) to the framing members of a charpente building. The lathing could even be applied both inside and out.

Rubble-stone structures also required the protection of a rendering, traditionally a jointing or pointing procedures, known as crépi à pierre apparente. As the name suggests, the crépi shielded bonds and bedding joints while leaving a degree of the stone exposed. The greater the amount of crépi the less the face of visible stone. Two less frequent but more expensive lime and sand renderings were: a rustic crépi finish by itself, or a polished enduit to follow.

In Europe a lime-wash often followed an exterior crépi or enduit, although the degree to which this practice was followed on Isle Royale is unknown. The standard Isle Royale military recipe for lime-wash specified two coats of lime slaked that day, with the second, containing glue, to be applied only after the first had dried. Unfortunately, these specifications were meant for interior crépis and enduits only (and never for wood).


Mortar and non-mortar renderings were no match for the Isle Royale climate, particularly when questionable techniques such as salt in the mortar reduced their effectiveness to an average life span of just three years, and expensive annual repairs to both fortification works and king's buildings became the result. By the early 1730s the situation with bonds and caulking had reached a critical state; it was simply becoming too costly to replace the earthen caulkings that were routinely falling from buildings each year. It was, therefore, inevitable that a change in technique, the introduction of the bevelled weatherboard, occurred. The course of change was also evolutionary.

The bevelled weatherboard, although used as a sheathing beneath clapboards in New England, at least as early as 1700, likely evolved on Isle Royale out of local roofing techniques. By 1713 Newfoundland builders had switched from laths to boards as a sheathing for wooden roofing shingles. On Isle Royale laths again reappeared, and boards too, with butt joints, but as a sheathing for slate and shingled roofs they were a failure. Then, in the 1730s, the bevelled roof sheathing board appeared, along with the bevelled weatherboard.

The use of weatherboards was not regarded as an opportunity to dispense with a fill entirely, as was the practice in New England.

Weatherboards, known locally as Boston boards, a softwood probably pine, occasionally planed but usually left rough, and imported from New England as a board (one pouce thick) or as a plank (2 pouces), were placed horizontally but not in the overlapping clapboard style that was popular in the American colonies. Rather a bevel of 2 to 4 pouces along their lengths (it is not known whether or not they were imported pre-bevelled) made for ease of application: the boards were nailed directly to the walls of piquet and charpente buildings, bevel overlapping bevel, to produce a flush finish. Masonry constructions, of course, would have required the added expense of wooden nailers. A cross-section of the Frederick Gate and an elevation of the Block 13 hospital illustrate weatherboard characteristics quite clearly.

Weatherboards with bevels would not have been suitable in vertical applications such as suggested. Boards or planks with tongues and grooves instead, always in good supply, would have proven more weatherproof.

Weatherboards, whether applied horizontally or vertically, or shingles, were natural choices for the upper triangular gabled areas of roofs.

It is not known if builders routinely infilled the upper gables prior to the placing of weatherboards or shingles. A few non-weatherboarded piquet building views illustrate piquets at these locations, but those contacts that called for weatherboards, suggest, albeit ambiguously, that builders did not always first insert a fill.

A proper retrofit of masonry with bevelled boards or planks, according to military specifications, meant not only the use of wooden nailers but, significantly, the added task of embedding them in the rubble-stone. Iron cramps were to fix them firmly. Embedded nailer dimensions and spacings varied: 4 by 4 pouce common rafters or 7 by 8 pouce pine timbers, for example, were usually spaced 4 pieds apart; though in one case the distance was 4 pieds 10 pouces. Planks not exceeding 12 pieds in length, or 14 pieds 6 pouces (given the use of four vertical nailers) or 9 pieds 8 pouces (three nailers) of at least one pied in width, fastened by two 6 pouce nails to a nailer, were acceptable.

Some military variations included half-laps rather than bevels, and possibly no embedding of nailers at all if, for example, a building wall were only one pied 6 pouces thick. In this case the nailers were probably fixed with iron clamps against the wall, not unlike the procedure for the interior finish of a certain powder magazine. Embedding, quite obviously, would have weakened any wall and, in fact, was a technique of some were quite critical. They believed that the practice of embedding the nailers in fortification works, to prevent the enemy from using them to scale the walls once the wooden facings had rotted away, was causing more damage to the walls than if no protection had been taken in the first place.

Others disagreed, inferring that previous engineers had shown a total disregard for quality control in the construction of masonry works, and so wooden facings could not but help. Certainly a wooden covering would allow the original mortar to at least dry, preventing further buckling. However, they did not favour wooden facings on new works, instead encouraging the use of better materials in original construction.


Aesthetic reasons perhaps lay behind much of the desire to whitewash or paint interior walls. Yet it was a practice with few followers. Those that did bear the cost were lime washing a mortar finish in every case (never a wooden wall). Even fewer chose to use paint.

Painters could choose to use either an oil or a water-based distemper paint, with a variety of pigments. Available mixing materials were water, linseed oil, nut oil, milk, glue, turpentine, lime, white lead, whiting, a variety of ochres, vermilion and other pigments. Required equipment included paint brushes and stone pestles for grinding the paint.


Owners might chose to finish off interior walls with earth-based, mortar-based, or gypsum-based renderings, or with wood. Of the renderings a lime-based crépis or enduit of the same range of quality as for an exterior wall finish was the most popular choice (the smoothing enduit being about 2 1/2 times more expensive than the coarser crépis). Laths were optional. Despite the added cost, one owner might prefer an enduit inside and out. In contrast, another might place the expensive enduit-crépis combination finish to particular walls only; for others, crépissage à pierre apparente was the finish, a technique which would have left the faces of the stones visible.

Clay-based and gypsum-based renderings, though used, were not popular finishes. Laths, for clay-based renderings, were a possibility, A clay finish with a lime-based rendering could be used in a kitchen. Gypsum (plaster) found its way into some fireplaces, onto some masonry walls, and over the interior piquet partitions and window and door jambs of some houses. Plaster, however, was not readily available, stockpiling was expensive, and wastage was high.


A more popular interior finish was wood, by itself, or together with a nearby mortar rendering. Known as a lambris, it consisted of one pouce tongued and grooved boards (local or from Boston), planed on the visible side, and then nailed vertically with top and bottom mouldings or tringles, perhaps only 1/2 pouce high. Tringles were in general use, but cornices and moulded tringles en facon de corniche (perhaps anywhere from 4 pouces to one pied high) did get placed on occasion: cornices, an architectural detail, were expensive, time consuming to produce, and required skilled labour to develop the proper angles. Moreover, they used a considerable quantity of wood, whether they were made of oak (which was preferred) or pine or fir.

As with a rendering, lambris was placed anywhere it was thought necessary: walls, dormer and window embrasures, around stair wells, above doors, beneath windows, or on door casings - even to hang a tapestry. There were, however, more elaborate finishes as well. Carpenters might install panels above and below doors and windows, or place lambris with panels (wainscot) and cornices. Remodelled with panelled lambris was also a possibility. Panelling, produced from dry, good quality boards of one pouce thickness, planed one side and assembled with tongues and grooves, and including the tringles and the nails, was an expensive proposition costing 27 livres the square toise (compared to 12 livres, and sometimes considerably less, for common lambris).


In either case, casement or double hung, the clear - sometimes specified white - rectangular panes, which were small and always in good supply owing to the traditional French mass production techniques of the time, were held in place by iron points or nails at each corner. The caulking was either paper glued in place, or beginning in the 1730s, a lime/cement mastic putty (possibly linseed oil and white lead were ingredients too).


Finally, there was the Custom of Paris, in part a building code based on principles of privacy, which, given the proper circumstances, could inspire window design or even dictate their absence. Articles 200-02, which discuss the close relationship of windows, their distance from a neighbour's property line and the joint ownership of a party wall, set these circumstances. If, for example, a building wall were greater than 6 pieds distant from a property line, and it faced a neighbour's property directly, there were no restrictions with respect to the placing of any opening, be it a window, doorway or similar viewing advantage. There were also no restrictions if the wall were at right angles to a property line and the opening was greater than 2 pieds from the line.

A closer distance, however, was another matter; whether a neighbour had developed this property or not was meaningless. Unless there was a written or verbal agreement to the contrary the sill of a ground floor window had to be at least 9 pieds above floor level. For upper storeys, excluding those with dormers (except if one could look perpendicularly at a neighbour's house), the height of the sill could be no less than 7 pieds. In either case, a home owner had to fix such windows in plaster so they would not open, and he had to insert bars - in trellis form with no more than a 4 pouce opening between the bars.

The Custom of Paris had a strong legal grounding on Isle Royale. Consequently, it was always best, though not always done, to surrender by written title any rights the Custom guaranteed. Otherwise, oral agreements notwithstanding, litigation proceedings sometimes developed.


Most owners preferred the traditional French style croisée a deux battants or French style 2-leaf window where the two sashes opened inwards. There were those, however, who chose or proposed to use the English style chassis a coulisse or double hung window. Among them were private builders, who used them throughout the period, and the military, who often proposed their use.

Many of these double hung windows were imported from New England.


Fir frames rotted quickly and required early replacement, and so carpenters preferred those of oak or even of pine. One and one-quarter pouces was a common thickness, as was that size for the sash and muntins too. Width, however, varied: 2 1/2 pouces for oak, 3 pouces for pine. In yet other examples some frames were derived from one and 2 pouce boards and planks normally reserved for partitions while others, of a special nature, for the Louisbourg lighthouse, were of oak, 3 pouces wide and 2 1/2 pouces thick with sashes 2 pouces by 2 1/2 pouces deep.

Quarter round mouldings for sashes, half-round profiles for muntins with mitred joints, mortise and tenoned frames, and sash drip mouldings were common. Pane size varied, however, though 7 by 8 pouce panes, arriving from France usually pre-cut, dominated the local economy. Six by 9 pouces was a large domestic pane and 5 by 6 pouces was a small one, with a variety of sizes in between, even on the same house. Most unusual, though, were the panes required for the Louisbourg lighthouse, rebuilt after the fire of 1736: 9 pouces 11 lignes by 7 pouces 7 lignes by 2 lignes thick.


An alternate practice would have been to set the panes in lead rather than to caulk them in wooden muntins as above. It is difficult to say whether this approach was ever taken on Isle Royale. Certainly the diamond shaped panes were sometimes proposed, but, as several cleaning payments reveal, it was glass panes caulked with paper that were being maintained.


Glazing was not mandatory in every case - one owner even used glued sailcloth - and sometimes shutters alone sufficed, with or without window frames. A storehouse, a forge or even an inexpensive home were strong candidates. Sometimes only iron bars and/or shutters were introduced to finish off a window. Bars, 2 pieds long, one pouce thick, were one type used.


The joinery work and glazing were prime candidates for maintenance, with twice-yearly inspections, in April and October, thought prudent. Broken panes would be replaced with those of equal size and quality and, at least once a year, all panes might be washed (probably using brushes), and re-caulk by gluing new paper in place.

Repairs were apparently effected with glass panes pre-cut to size in France and shipped to Isle Royale by case or box.

The degree to which window frames, indeed the exterior surface of any part of a building at all, was painted is a moot point, and is a question which comprises the larger issue of exterior finishes in general. An inescapable conclusion, however, is that few window frames were painted, owing to a supply problem.


The popular window opening size was 3 by 5 pieds, though of course almost any size was possible. Within these openings builders preferred a window with two sashes, totalling either 20 or 24 panes, but as many as 48 or as few as two occurred. Even the number of panes to a window varied for the same house. For example, one residence had windows of 4, 8, 12, 16 and 24 panes, while another might have 24-pane windows for the ground floor but only 20-pane ones in the upper storeys.

A window with 12 or fewer panes was unlikely to have had a double sash. A small window, it might be fixed in place. If it opened, then it was probably of the single casement type.

Windows were often placed on the inner side of the walls. In a masonry house that might mean flat stone jambs with an inside rabbet to take the window frame.


Exterior storm windows, perhaps of pine or oak, are a possibility but how often used, or even if placed on every window opening of a building, is unknown. Although storms cost less than an ordinary window, their fittings would have adding substantially to the final price. Also, the need to caulk their exterior joints with a mastic of slaked lime and cement would have been a routine procedure.



Formed by cutting down many entire trees, the branches of which are turned towards the enemy, they are made, for example, before a redoubt, to render an attack difficult.


A step running inside the parapet for the troops to stand on while firing over the parapet.


A platform on which cannon are placed to fire over the parapet.


A projecting part of a fortification, usually having two faces which are connected to the curtain walls by two shorter walls called flanks.


A number of guns placed regularly for combined action; also a platform where cannon are placed within a fortification.


A fieldwork of earth thrown up breast-high, a sort of makeshift parapet.


A passage made in a dry ditch from one work to another; a structure to provide flanking fire to cover the ditch.


A vaulted chamber built into the rampart.


A heavily constructed structure, generally raised 10 to 12 feet above the body of other works, to command the adjacent works and the country about it. A battery, protected by stone parapet, is often located on its flat roof.


The uppermost course of masonry on a wall, usually sloping to avoid accumulation of water.


A round projection of stone near or on the top of walls and escarp to obstruct scaling ladders.


A solid piece of masonry built behind the walls to strengthen them; often placed at 18 foot intervals.


Wall of the covered wall, on the outer side of the ditch.


A kind of road around the fortress on the outer side of the ditch which is protected by a small parapet created by the glacis and equipped with a banquette for the infantry to cover the glacis.


The part of the fortification which connects two bastions.


A bastion having only one face and one flank.


Originally a crescent-shaped earthwork to protect the front of a curtain or flank a bastion. Later evolved into a detached bastion.


An uncertain number of men drawn out from several regiments or companies.


A large, deep trench made around the whole body of works, generally 15-18 feet deep and 50-100 feet wide. Earth excavated from this trench serves to raise the ramparts, parapets or glacis. When it contains water, it is called a wet ditch. Most engineers preferred dry ditches because of maintenance problems. The ideal solution is where the ditch can be inundated during a siege 46


An opening made in a parapet for cannon. They have widening angles from within to allow maximum sweep while affording cover for the cannoneers.


The entire system of walls comprising the fortifications; the interior wall or rampart which surrounds a place, sometimes composed of bastions or curtains.


A kind of breast-work to cover the troops in front, and sometimes in flank; term frequently used for any work thrown up to defend the flank of a post, or any other place.


The exterior face of the rampart.


That is the two front sides, reaching from the flanks to the salient angle of the bastion.


They are a kind of faggots, made of small branches of trees or brush-wood, tied in 3-6 places, and can be of of various dimensions. (e.g. 1 1/2 feet to 10 feet long).


That part which joins the face to the curtain, comprehended between the angle of the curtain and that of the shoulder.


A small fortified place, enclosed on all sides with a ditch, rampart, and parapet.


They are a kind of baskets, without a bottom, made of ozier-twings, of a cylindrical form, having different dimensions (e.g. 1 to 5-6 feet high).


A gentle, sloping earthwork, commencing from the covered way and stretching towards the countryside.


A shelter for sentries.


A small round or oval work, with a parapet, generally made in a ditch, or in a marsh.


A narrow vertical opening, normally wider on the inside, for musket fire.


In ancient, and sometimes in modern fortification, that upper part of the wall which is sustained by brackets or corbels, jets out and overlooks the gate or ditch.


The summit of the parapet between two embrasures.


That part of a bastion, near the shoulder, which serves to cover the retired flank from being seen obliquely.


Strong, pointed wooden stake. A number of them fixed deep in the ground and in close proximity create a defensive work. Often placed parallel to the covered way on the glacis.


A defence of earth or stone to cover the troops and armament from the enemy's fire and observation.


Essentially any place where the troops may gather.


A tunnel, serving as a means of access to the ditch or outer works.


A mound of earth for the defence of a place and capable of resisting artillery fire.


Type of indented (like the teeth of a saw) work, consisting of lines or faces, that form sallying, or re-entering angles, flanking one another.


A detached work beyond the glacis, but within small arms' reach; small self-defensive, heavily constructed works without flanking protection, and located at strategic points.


Angle created by the joining of the flank of a bastion with the curtain; that which turns its point towards the centre of the place.


Any work raised to cover a post, such as fascines, loaded with earth, gabions, sandbags, etc.


A retaining wall of masonry supporting the face of the rampart; a strong wall, built on the outside of the rampart and parapet, to support the earth.


A rising ground or eminence, commanding a plain, sometimes almost parallel to the works of a place, serving to cover a camp, or to give an advantage to a post.


Angle created by the joining of the bastion's two faces; that whose points turn from the centre of the place.


An opening in the main body of the fortified works to allow passage of troops.


Angle created by the joining of the face and flank of a bastion.


A low rectangular work in the ditch for musket fire.


Level surface of a rampart between the parapet and the rampart's slope or talus; also the level surface enclosed by a bastion.


Obstruction placed on the covered way to hinder enemy movement and to protect covered way from enfilading fire.



  • 12 Lignes = 1 Pouce
  • 12 Pouces = 1 Pied
  • 6 Pieds = 1 Toise
  • 1 Pouce = 1/72 of a Toise
  • 1 Pouce = 1.0656 Inches (1 1/16 Inches) or 2.707 Centimetres
  • 1 Pied = 1.066 Feet (1 Foot 0 13/16 Inches) or 32.479 Centimetres
  • 1 Toise = 6.396 Feet (6 Feet 4 3/4 Inches) or 194.874 Centimetres


  • 12 Deniers = 1 Sol
  • 20 Sols = 1 Livre
  • 1 Livres = 24 Deniers



10 Livres 13 Sols per Toise


8 Toise 5 Pieds 8 Pouces


95 Livres 5 Sols 2 Deniers


(01) 10 Livres 13 Sols = 213 Sols = 2556 Deniers)

(02) (8 Toise x 2556 Deniers = 20,448 Deniers)


(5/6 Toise x 2556 Deniers = 2,130 Deniers)


(8/72 Toise x 2556 Deniers = 284 Deniers)


22,862 Deniers

(03) (22,862 Deniers 240 Deniers = 95 62/240 Livres)

(04) (62/240 of a Livre x by 20 Sols = 5 40/240 Sols)

(05) (40/240 of a Sol x 12 Deniers = 2 Deniers)



10 Livres 13 Sols per Toise


8 Toise 5 Pieds 8 Pouces


95 Livres 5 Sols 2 Deniers


(01) (8T x 10 L = 80L) + (8T x 13S = 104S [5L 4S ) = 85 Livres 4 Sols

(02) (5/6T x 10L = 8 2/6L [8L 6 4/6S or 8L 6S 8D])


(5/6T x 13S = 10 5/6S [10S 10D] = 8 Livres 17 Sols 6 Deniers

(03) (8/72T x 10L = 1L 8/72L [1L 2 16/72S or 1L 2S 2 2/3D]


(8/72T x 13S = 1 32/72S [1S 5 1/3D] = 1 Livres 3 Sols 8 Deniers


95 Livres 5 Sols 2 Deniers