This project takes advantage of a niche infill tool in Austin’s land development code called ‘Small Lot Amnesty’ to build a house for a family of four on a lot less than half the size of the city’s required minimum for single-family homes.
Using a series of ‘code tricks’ we enlarged the existing 700sf 1-bed/1bath house to a two-story 4-bed/2-bath house, while abiding by onerous setbacks intended for much larger lots. The existing house encroached into these setbacks by a few inches on both the east and west sides. The original desire was to build a simple second story box that extended over the first floor, making detailing and waterproofing straightforward. However, this goal was hampered by a limitation on increasing the height of non-conforming existing walls. The solution was an inventive ‘double wall’ section, qualifying as a passive energy feature, which located the conditioned envelope - window, insulation and waterproofing - within the allowable building area, while an outer metal-clad wall extends a foot over the setback.
On the interior, we kept the existing 8’ ceilings on the ground floor for simplicity and compensated with roomy vaulted bedrooms on the second floor and a double height stairwell. The plan is compact but livable, with three bedrooms sharing a family bathroom upstairs, an office nook tucked under the stairs and a flex room on the ground floor which is alternately used as guest room, play area and workout space. Skylights bring in generous natural light where a 1-hr fire rating limited windows on the west wall.
The density of this project is almost 75% higher than Austin’s base single-family zoning allows. Nonetheless, it sits comfortably in its neighborhood context, offering a prototypical housing model for retaining both neighborhood character and middle-class families in Austin’s increasingly expensive central core.