LA County has no countywide BMO like LA City, but Title 22 Chapter 22.110 sets hillside grading and bulk limits, and several Community Standards Districts cap floor area ratio in unincorporated communities like Altadena, La Crescenta-Montrose, and Topanga.
Title 22 (Planning & Zoning) of the LA County Code regulates residential bulk through several pathways rather than one mansionization ordinance. Section 22.110.090 imposes hillside development standards: graduated height limits, ridgeline protection, and grading caps tied to slope. Roughly 20 Community Standards Districts in Title 22 Division 6 add neighborhood-specific FAR caps, lot coverage maximums, and second-story setback rules — Altadena CSD limits FAR to 0.45, La Crescenta-Montrose CSD adds daylight planes, and Topanga CSD restricts mass on visible hillsides. Department of Regional Planning reviews projects; large additions in CSDs need Director's Review or a hearing.
Stop-work orders and permit revocation for exceeding FAR or hillside limits. Title 22.60 administrative penalties run up to $1,000 per day. Illegal grading triggers separate Title 11 civil penalties and restoration orders under Public Works supervision.
Other ordinances people look up for this city. Green dot = verified primary-source excerpt.
Altadena, CA
LA County allows backyard chickens in R-1 zones in unincorporated areas (including Altadena) subject to coop setbacks under LA County Code Title 10 and Title...
Altadena, CA
LA County Code Section 10.32.010 prohibits dogs running at large in any public place or private property other than the owner's, unless restrained by a chain...
Altadena, CA
Trimming protected oak trees (≥8 in DBH) requires an Oak Tree Permit if the work enters the protected zone or removes >25% of crown. Street trees in the publ...
Altadena, CA
In Altadena's Very High Fire Hazard Severity Zones, grass and weeds must be kept under 3 inches under LA County Fire Code Title 32 defensible-space rules.
Altadena, CA
LA County Fire's Brush Clearance program also functions as the weed-abatement ordinance — vacant and improved lots must keep weeds and grasses cut to under 3...
Altadena, CA
Outdoor watering in Altadena (served by Lincoln Avenue Water Co., Las Flores Water Co., Rubio Cañon, and Kinneloa Irrigation District) is limited to 2 days p...
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