Plan Check Language Library · Mount Washington
Section 6.A of Ordinance 168,707 sets a sliding-scale Floor Area Ratio that grows more restrictive as lot size grows. Five brackets, two of them flat, three of them formulas. The Specific Plan’s Floor Area definition in Section 3 expands what counts — covered parking and basement storage are in. The April 2025 application checklist requires the calculation to appear on the cover sheet of the architectural plans, performed using the Specific Plan definition rather than the LAMC’s. The combination produces a smaller buildable envelope than most owners assume from the lot record alone.
The Five Brackets
Section 6.A overrides LAMC Section 12.21 for One-Family Projects in the Specific Plan area and sets the ratio by lot size in five brackets. The brackets at the small and large ends are flat. The middle three are formulas.
| Lot Size | Maximum FAR | Worked Example |
|---|---|---|
| < 5,000 sq ft | 0.5 : 1 (flat) | 4,500 sq ft lot → 2,250 sq ft FA |
| ≥ 5,000 and < 10,000 | 0.50 − [(LA − 5,000) × 0.10] ÷ 5,000 | 7,500 sq ft lot → 0.45 FAR → 3,375 sq ft FA |
| ≥ 10,000 and < 15,000 | 0.40 − [(LA − 10,000) × 0.08] ÷ 5,000 | 12,500 sq ft lot → 0.36 FAR → 4,500 sq ft FA |
| ≥ 15,000 and < 20,000 | 0.32 − [(LA − 15,000) × 0.05] ÷ 5,000 | 17,500 sq ft lot → 0.295 FAR → 5,162 sq ft FA |
| ≥ 20,000 sq ft | 0.27 : 1 (flat) | 25,000 sq ft lot → 6,750 sq ft FA |
The slope of the formula brackets is what catches owners. A 9,999 sq ft lot lands at the bottom of the second bracket — FAR 0.40, max 4,000 sq ft. A 10,000 sq ft lot lands at the top of the third bracket — same 0.40 FAR, but the formula now drops more steeply. Each additional square foot of lot above 10,000 reduces allowed Floor Area faster than each square foot below it added.
The Floor Area Definition That Catches People
Section 6.A’s brackets sit on top of the Specific Plan’s own Floor Area definition in Section 3:
“Floor Area is that area in square feet confined within the exterior walls of a building of a One-Family Project, including the area of stairways, shafts, covered automobile parking areas and basement storage areas, and excluding uncovered outdoor decks.”
Ordinance 168,707, Section 3
Three pieces of that definition do work the LAMC’s definition does not. Covered automobile parking areas count. A 400 sq ft attached garage adds 400 sq ft to the Floor Area number used in the Section 6.A bracket calculation. Basement storage areas count. A finished basement with storage rooms is counted whether or not it is habitable space. Uncovered outdoor decks are excluded — but only uncovered. A deck with a roof or other covering should be evaluated before the Floor Area calculation is finalized rather than assumed exempt.
The April 2025 Checklist Requires the Calculation on the Cover Sheet
Item 12.a.i of the April 2025 application checklist requires the architectural cover sheet to show:
“Total (gross) Floor Area (including covered parking area) based on definition (refer to Specific Plan Section 6.A) in Specific Plan, for maximum allowed and proposed.”
April 2025 Checklist, Item 12.a.i
For additions, the same item requires separate figures for total existing permitted, total existing unpermitted, and the new addition. The checklist is a current procedural filing requirement published by the Department of City Planning, not a provision of Ordinance 168,707; verify the current checklist before filing.
Why Section 2.B Matters Here
Section 2.B of the ordinance resolves the relationship between the Specific Plan and the LAMC. Where the Specific Plan contains more restrictive Floor Area Ratios than the underlying zone would allow, the Specific Plan prevails. For most Mount Washington and Glassell Park lots — particularly larger hillside lots — the Section 6.A brackets are more restrictive than the LAMC R1 base. The Specific Plan controls.
For owners running early feasibility, the practical sequence is: pull the lot area, apply the correct Section 6.A bracket, calculate the maximum Floor Area, then back out the program against the Specific Plan’s expanded Floor Area definition (covered parking and basement storage included). Programs sized against the LAMC’s Floor Area definition will overshoot the bracket once the Specific Plan calculation runs.
Design 1 Studio is a building design firm based in Pasadena, California. Over a decade serving Los Angeles County with residential and commercial design, including ADUs, hillside projects, multifamily, and historic-district work. Inspector-led methodology focused on producing drawings that anticipate plan check rather than react to it. Specialty work in Mount Washington / Glassell Park Specific Plan navigation. Contact through design1.studio.
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Design 1 Studio runs the Section 6.A bracket calculation against the Specific Plan’s Floor Area definition before drawings begin. The maximum allowed Floor Area, the program against the bracket, and the cover-sheet calculation the April 2025 checklist requires — all addressed at feasibility, not at correction.