The sworn master masons systematically report the number of floors but rarely their height. If our study does reveal a notable increase of the height on the street line, we can also state that over 40 % of the building patterns are rarely, if ever, represented in the printed models. Buildings with only a ground level and those with more than five floors are extremely rare. Houses with one or five floors are somewhat more ordinary while those with four floors increasingly so acccounting for 20 % of ordinary house construction from the second half of the 17th century through the 18th century. Meanwhile buildings with two or three floors decrease in number over this same period. The increase in height is illustrated through reconstructions of houses from the middle of the 18th century, with two floor houses replaced by four floor houses.
The architectural grammar of Parisian ordinary houses is a contrast of openings and walls, as evidenced by the size and spacing of the doors and windows whose height progressively increased in the upper levels. The reports often specify the number of the bays facing the street but rarely their dimensions (a bay is not a mesure). In the mid 18th century, a new generation of houses was characterised by more openings and fewer walls. Four-bay façades gradually replaced the two-bay ones often without any increase in size. This developement corresponds to the advances in glass production from the second half of the 17th century, with the introduction of wooden framed square glass panels. Recent and uniform models are thus reported in the street façades, as is the re-use of old and often mixed windows for the secondary façades (filled with paper, textile, glass in lead pannels and/or modern square glass pannels in wood). Our study counts houses with between one and seven street-facing bays, of which about a third were two-bay façades measuring 5 to 9,6 m. Other houses with a façade of similar dimensions were divided into three, four or even six bays; the broader façades, measuring 10 to 34 m, were divided into three to seven bays. According to our written sources single bay façades seem to have been more ordinary inside the plots of land.
Although the design of the façades largely followed a tripartite formula comprised of a ground level, “floors” and a roof, the balance of the composition often depended upon the organization of the ground level that was distinguished by the door, shop/s and often an entresol (a half-floor). The entrance door was traditionally placed on one side of the façade and opened onto a corridor leading to the stairs and a courtyard. Several drawings reveal an attempt to hide this asymmetry. The entrance door, frequently maintained when the house was reconstructed, was a prestigious element of the structure and its size or category allows for classification of the house: piétonne, bâtarde or bourgeoise, charretière or carriage door. The central space consisted of two to four floors, divided into regular, sometimes false bays that were often contrasted by horizontal mouldings. Since additional ornamentation increased the price of construction and any overhanging required explicit, administrative authorisation and thus an extra cost for the builder, only some newly built houses from the second half of the 18th century reveal the use of more elaborate doric ornaments. Black iron works, brackets, keys, masks and mouldings were more ordinary. For the upper level our period corresponds to the progressive abandon of the gable for the gutterwall on the street line, through which the broken Mansart roof became a classical feature of Parisian ordinary houses. Adorned with dormer windows these roofs enhance the overall aesthetical design of the ordinary house. The slope of the roof facing the street was sometimes covered with slate and the dormer windows either crowned the bays or were placed intermittently between them should there be fewer windows than bays. They could be supported by the entablature or sunk into the roof and their framing, in stone or wood, could be more or less elaborate (rounded, square, with a pediment or doubled).
The architecture of Parisian Ancien Régime ordinary houses thus demonstrated a simplified yet wider array of designs and scales than the printed models suggest. Though the typology is far from being consistent, we can distinguish two main groups according to scale and interior organisation, as suggested by François Loyer: shared houses, buildings with a superposition and a juxtaposition of unspecialized rooms that might also be defined as primitive houses; and bigger rental houses including a succession of horizontal “apartments” opening on a ordinary staircase. The development of the latter was recently studied by J.-F. Cabestan.
Oriented on a rectangular plot of land with the shorter side facing the street and one or more somewhat identical buildings inside, the simple primitive house was the basic feature of the Parisian ordinary house. The ground floor was divided into an entrance corridor with one or two rooms on either side that opened onto a court-yard with a stair-case leading to a superposition of rooms. The juxtaposition of two primitive houses behind one façade created a twin house that was ordinary in Paris throughout modern times. This model was regularly used in larger urban programs and corresponds to the floor plan of many houses built during the 18th century. A third feature, not represented among the printed models, was the double-twin house.This category of house, for which we can establish three manners of use, evolved over time: those clearly divided on all the height of the house, those with a single appartment on each floor and those with open planning possibilites. Those houses built on a larger scale could otherwise be classified as a “pre-apartment house”. A fourth feature of the primitive house was a split layout with a succession of composite primitive houses on a bigger plot of land. The first, larger-scale ordinary houses present a juxtaposition of primitive house plans behind a uniform façade. Other structures include mansion houses that had been divided into bigger rental houses.
Economical, flexible and consistent, were the main characteristics of the Ancien Régime Parisan ordinary house. Under these unifying characteristics we can establish how, much like a puzzle, this architecture could be adapted easily through a juxtaposition of dwelling units or rooms and thereby establish a clear connexion between the different layouts of collective housings. In fact the primary difference between a primitive ordinary house and a pre-apartment house is one of scale: going from a vertical to a horizontal composition. We can also state that the primitive house was not replaced by the apartment-house, but rather that their coexistence is obvious all through the Ancien Régime.