How the permit size limit is measured: floor area, roof area or inside the walls
The 15 permit exemptions here measure the size limit in different ways. Seattle and Denver count roof area. Portland measures floor area from the inside of the walls. Oakland and the City of San Mateo write the limit as less than 120 sq ft. The table lists the method for each city and county.
| Measured as | Cities and counties |
|---|---|
| Roof area | Seattle |
| Floor area inside the exterior walls | Portland |
| Floor area | Washington County, Austin, Los Angeles, San Mateo County (unincorporated), Citrus Heights, Sacramento County (unincorporated) |
| Projected roof area | Denver |
| Aggregate floor area | Phoenix |
| Area, basis not listed | San Jose, Oakland, San Mateo (city) |
| Floor area in the FAQ, projected roof area in the code text | San Francisco |
| Any dimension over 12 ft | Raleigh |
Source: the city and county pages listed under Sources and on each city or county page.
Roof area
Seattle counts the footprint of the roof, and Denver counts projected roof area. Roof overhangs extend past the walls, so roof area is larger than floor area. Calculated: a 10 x 12 ft floor is 120 sq ft. A roof that extends 1 ft past every wall covers 12 x 14 ft, or 168 sq ft. None of the three manufacturers here lists roof overhang or roof area.
Floor area inside the walls
Portland measures floor area from the interior of the exterior walls. Wall thickness is not counted under that method.
Less than 120 sq ft and 120 sq ft or less
Oakland and the City of San Mateo write the limit as less than 120 sq ft. A 10 x 12 ft building is exactly 120 sq ft, so it is not under that limit. The other 120 sq ft rules use the words “does not exceed”, “or less” or “not greater than”, which include 120 sq ft.
Sizes listed by the manufacturers
Studio Home and Kanga list sizes in feet, such as 10 x 12 and 12 x 14. Autonomous lists one floor area for each pod: 80, 102 and 105 sq ft. None of the three states whether its size is measured inside or outside the walls.
The building department for the address decides whether a permit is required. This site repeats published rules and compares them with published pod sizes. Zoning rules, HOA rules and setbacks can also apply.