1100 sq ft ADU Plan – Permit Ready

A 1100 sq ft single-story two-bedroom ADU with an open-plan layout configured for family rentals and multi-generational living. The layout configures 2 bedrooms and 1.5 baths within a clean, code-aware envelope. Suitable for tenants who want full-house features in an ADU footprint, or homeowners planning ahead for single-level living later in life. The plan includes an open porch.

Front 3D isometric rendering of a 1100 sq ft 2-bedroom 1-story ADU plan in California — Exterior rendering of the 1100 sq ft permit-ready ADU plan designed as a detached backyard cottage.

Plan A12-1100 Specifications

Base area	1,100 sq ft
Bedrooms	2 Bedrooms
Bathrooms	1.5 Bath
Stories	1-Story
Ridge height	14 ft
Ceiling height	9 ft
Roof slope	4:12
Open porch	100 sq ft

Code & Engineering

Delivered as a permit-ready architectural plan set, this 1100 sq ft single-story ADU configures 2 bedrooms and 1.5 baths for California parcels eligible under the state's detached-ADU statute.

The architectural plan set comprises the floor plan, exterior elevations, sections capturing the roof-line and interior heights, and dimensioned framing intent. The design follows the California Residential Code (CRC) and is engineered for structural detailing per ASCE 7 and the NDS.

The Structural Set package is offered as a separate scope and includes lateral analysis, gravity load takedown, shear-wall design, and component-level connection details — all sized to the specific site's seismic and wind conditions rather than to a generic California average.

Foundation design is provided as a separate scope to match the right system to each site. Common alternates include slab-on-grade for stable parcels, shallow crawl-space on stem walls for expansive-clay or moisture-prone sites, and pier-and-grade-beam systems for hillside lots, soft soils, or any site where the geotechnical report identifies a need for deeper bearing.

The plan's 14 ft ridge height fits within California's standard 16-foot detached-ADU height limit on any standard parcel — no special transit or zoning eligibility required. Side and rear setbacks of 4 feet are respected, and the plan is designed for ministerial review under §65852.2. For sites with stricter local height overlays (HOAs, hillside districts), plan customization is available to lower the ridge further if needed.

Available optional services: PE-stamped structural calculations, plan customization for site-specific adaptations (roof slope, elevation, interior layout), custom foundation design sized to the geotechnical report, structural observation visits during framing and finish, and permit support tailored to jurisdiction-specific requirements.