Commission signals it may scrap slope-based floor area limits after finding 65% of lots don't comply

A Planning Commission subcommittee — Commissioners Wagstaff and Campbell, working with Council member Margaliz — reported Wednesday that only about 35% of Larkspur's residential lots comply with the city's current slope-based floor area ratio rules. The finding framed a long discussion about whether a standard that most houses in town already fail is a standard worth keeping.

“My neighbors are just incensed and they're going, 'How did you let that happen?'”— a Planning Commissioner, on fallout from exception decisions

The alternative on the table is Corte Madera's model, which drops the slope adjustment entirely and tiers allowable floor area by lot size. Applied to Larkspur's lots, staff said roughly 86% would comply — and under that model, no exceptions would be allowed. Commissioners also weighed a more sweeping option: eliminating FAR altogether and regulating a house's bulk through lot coverage, height and setbacks instead. Much of the safety logic behind the slope-based reductions, commissioners said, has been overtaken by modern building and engineering codes.

New Community Development Director Andy Mogensson noted that state housing law doesn't account for floor area ratio at all — neither ADU rules nor SB 9 — which is part of why the local numbers no longer line up. He urged the Commission to ask what work FAR is actually doing, calling it one of the oldest tools in the box but not the only one. Commissioners returned repeatedly to enforceability: a rule most properties violate pushes decisions into case-by-case 'exceptions' (staff and legal noted the city uses that term, rather than 'variance,' which has a specific meaning under state law), which in turn invites the kind of neighbor blowback one commissioner described from personal experience.

No vote was taken. The consensus direction was that a Corte Madera-style approach looks promising, and staff will bring back worked examples for further review. The subject is also expected to surface at the City Council's broader zoning code discussion on February 7.

Also raised: how ADUs, which the state largely shields from local limits, eat into lot coverage math — one more reason commissioners want standards that are simpler and more objective.