One of the most distinctive features of art deco houses is their parapet walls, which conceal flat or low-pitch roofs.
A principal feature of art deco houses was the parapet wall. Behind the parapet, the roof was low to enable the parapet height to be kept to a minimum. The roof was either flat, if it doubled as a deck or roof terrace, or was very low-pitched, typically 10º or less.
Parapets could be:
- continuous around the building, or
- partial around front and side walls only.
If the parapet was continuous, the roof was either flat or had a ‘butterfly’ shape, i.e. the highest parts of the roof were on opposite sides of the building with slopes falling towards a central gutter that, in turn, drained to a rainwater head (Figure 1). In a variation of this roof configuration, the roof was effectively an inverted hip with two valley gutters running from corners of the roof to the central gutter.
If it was a partial parapet only, the roof was a single slope or mono-pitched, with the slope falling towards an external eave gutter. The eave gutter was generally located at the rear of the house and there was seldom an eaves overhang. Where a single parapet wall stepped down, the highest part would be located facing the street and indicate the highest part of the roof.
Some houses also had a shelf running around the house below the parapet but above the windows (Figure 2).
The configuration of some art deco houses, such as those with the main house layout as a simple rectangle, featured one or more smaller, flat-roofed rectangular or semicircular add-ons. The main part of the house was defined by a higher parapet than the add-ons, and the walls of the add-ons generally reduced in height towards the rear of the house, particularly if there were several additions.
Entry porches were generally only a shallow recess in the front or a side wall of the house but, to increase the level of shelter provided, there was often a flat-roofed canopy projecting out beyond the wall (Figures 2-3). The canopy roof often had no specific drainage provided from the roof surface. If the canopy did not have a small fall away from the house, there could be a tendency for water to pond or gather at the junction between the canopy roof and the external wall.