Residential Floor Area

Residential Floor Area is the total floor area count used for residential plan check, defined inclusively. What counts toward RFA is broader than typical owner intuition: covered parking counts unless it qualifies for the limited exemption, solid-roof porches and patios count, areas with high ceilings count twice, and basements may count when the elevation thresholds above natural or finished grade are exceeded. RFA is the central floor-area number on a residential project — the figure that determines whether the design fits the lot.

LAMC §12.03, definition of Residential Floor Area, sets what counts. LAMC §12.21 C.10(b) and §12.21 C.10(c) govern hillside RFA calculation, verification, and the bonus increase pathways. PC/STR/Corr.Lst.20A Part II.L and PC/STR/Corr.Lst.107A Part II.A.2 walk through the inclusion and exemption rules in plan-check terms.

A correction that the proposed RFA exceeds the maximum allowed for the lot, often paired with a line-by-line accounting request: the covered parking count, the basement count, the high-ceiling count, the detached accessory building count. Plan check may also flag an internally inconsistent set of RFA numbers across the plan-set cover sheet, the floor plans, and the BHO calculations — a common pattern when the design has been revised mid-process and not all sheets were updated.

Treating the parking exemption as automatic, when the exemption is capped at 200 square feet for a single space and 400 square feet for two spaces; treating a solid-roof patio as not counting (it does); miscounting the basement when the floor or roof above exceeds the height threshold above natural or finished grade; or running the RFA math on an addition without including the existing footprint.

RFA may govern the buildable program more than any other single rule on a residential project. Getting it wrong typically produces a redraw, which could be substantial if upper floors have to be reduced to bring the total within the limit. Where the lot qualifies, an RFA bonus increase under §12.21 C.10(b)(3) may be available, but pursuing the bonus typically requires meeting specific landscape, design, or open space conditions and is not a remedy that resolves quickly.

Slope Band Analysis (where the maximum allowable RFA on a hillside lot is calculated), Maximum Envelope Height under the BHO (because RFA distribution typically interacts with the height envelope), Lot Coverage (because RFA and lot coverage are independent caps that may bind separately), and the State Preemption Footnote entry (where RFA limits may be overridden for protected ADU configurations under state law).

Verification: RFA definition lives at LAMC §12.03. Hillside RFA framework at §12.21 C.10(b) and (c). PC/STR/Corr.Lst.20A Part II.L and PC/STR/Corr.Lst.107A Part II.A.2 are the plan-check forms of the inclusion/exemption rules. The 800-square-foot Guaranteed Minimum Residential Floor Area exemption pathway under §12.21 C.10(b)(2) confirmed at LAMC line 15445 with Table 12.21 C.10-3 reference. The 200/400 square-foot parking exemption caps and the high-ceiling double-count rule live within the §12.03 RFA definition; the definition itself is loaded but specific line citations for each sub-clause were not individually re-verified for this entry and may be added in a future revision pass.