Home Additions in Los Altos, CA
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Design Review for Los Altos Additions
Los Altos design review covers exterior alterations, additions and new homes in R1 zones, using the Residential Design Guidelines and a Neighborhood Compatibility Worksheet. An on-site Notice of Development Proposal sign and mailed notice let neighbors comment. In R1-10, floor area is 35% of the lot up to 11,000 sq ft, plus 10% of the area beyond that; lot coverage is 35% for one-story homes up to 20 feet and 30% for two-story homes; height is 27 feet with an 11-foot, 25-degree daylight plane at the side lines. We confirm current setbacks for your lot.
Addition Work
Sprinklers and Trees
Fire sprinklers (Los Altos local amendment): all new homes, and additions over 50% of living area, over 750 sq ft, or exceeding fire flow, counted cumulatively over 3 years and including garages. No waivers.
Trees: under Chapter 11.08, any tree 12 inches or more in diameter at 48 inches, and native trees at 10 inches, are protected, along with heritage trees. An arborist report is usually part of an addition submittal.
1 N. San Antonio Road, Los Altos, CA 94022 · City Hall (650) 947-2700
Building (650) 947-2752 · Planning (650) 947-2750 · Engineering and stormwater (650) 947-2780
Permits run through eTRAKiT, and Planning applications are electronic only. All inspections are scheduled online in morning (8:30 to noon) or afternoon (12:30 to 3:30) windows. Construction hours: 7 a.m. to 5:30 p.m. weekdays, 9 a.m. to 3 p.m. Saturday, none on Sundays or holidays.
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Other Los Altos services: Bathrooms · Kitchens · New Homes · Los Altos ADU builder · Los Altos overview
Same service nearby: Los Altos Hills · Palo Alto · Mountain View
Los Altos Home Additions FAQ
Does a Los Altos addition need design review?
Yes. Additions in R1 zones go through design review with a Neighborhood Compatibility Worksheet.
When does an addition need fire sprinklers?
Over 50% of living area, over 750 sq ft, or exceeding fire flow, counted over 3 years.
How tall can a two-story home be?
27 feet in R1-10, with a daylight plane at the side lines.
Are trees protected?
Yes, trees 12 inches or more in diameter, and natives at 10 inches.