Two-Story Garage-Conversion ADU – Vanowen St, West Hills CA 91307
This project repurposes a detached garage at the rear of a 7,600 ft² RS-1 lot into a modern, 765 ft² accessory dwelling unit. Golden ADU added a new second floor above the original slab, delivering open living space below and two private bedrooms above—while staying inside Los Angeles’ 21-ft height cap and 4-ft side-yard setbacks.
Project Overview
- Address: 22406 W Vanowen St, West Hills, CA 91307
- Scope: Garage conversion + new second-story addition
- Total ADU Area: 765 ft² (373 ft² ground · 392 ft² second)
- Height: 21 ft parapet (flat roof, 2 % slope to scuppers)
- Construction: Type V-B wood framing · 2 × 6 exterior walls
- Zoning / Setbacks: RS-1 · 4 ft sides · 5 ft rear · >75 ft from main house
- Sprinklers: Not required (detached ADU < 1 200 ft²)
- Design Team: Anthony Bueno AIA · MLB Consulting Engineering
Floor-by-Floor Layout
- Ground Floor – 373 ft²: Open living / kitchen zone, stacked W-D closet, ½-bath, and a 95 ft² storage bay retained from the original garage.
- Second Floor – 392 ft²: Two equal bedrooms, a shared full bath, linen closet, and a south-facing balcony (7′ × 3′-6″) overlooking the pool.
- Circulation: Straight-run stair along the west wall meets CBC width and head-height clearances.
Design & Compliance Highlights
The flat-roof form keeps construction simple and provides a cool-roof membrane (SRI ≥ 78) with a dedicated solar-ready zone to meet Title 24. Plywood shear walls and Simpson HDU hold-downs resist Design-Cat D seismic loads, while new pad footings reinforce the existing slab for the second-story framing. CALGreen measures include low-flow fixtures, MERV-13 filtration, and an EV-capable branch circuit to the driveway.