What is SB 1211? Unlock California’s ADU Law for Multifamily Properties

DRAMS Architects and Construction explain how to legally add 8+ detached ADUs—and convert even more interior space—without zoning battles.

As California scrambles to address the housing shortage, SB 1211 (2025) gives multifamily property owners a limited-time opportunity to add multiple Accessory Dwelling Unites (ADUs) by-right, boosting rental income and long-term property value—without needing variances, density bonuses, or discretionary approvals.

This legislation is already in effect, but it may not last forever. Future amendments or rollbacks are possible, so acting now could lock in your development potential.

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SB 1211: What’s Allowed on Your Multifamily Property

Under this new California ADU law, property owners can now:

Build up to 8 detached ADUs by-right per lot, regardless of lot size or existing zoning limits
Convert up to 25% of existing units into interior ADUs by repurposing non-livable spaces like garages, basements, storage rooms, and attics

Example: 15-Unit Apartment Building in Los Angeles

Let’s break it down:

Detached ADUs: Up to 8 allowed (capped regardless of unit count)
Interior Conversion ADUs: 25% of 15 = 3.75 → round down = 3 units

Total New Units = 8 Detached + 3 Interior = 11 ADUs

But if your property has multiple structures (e.g., duplexes, fourplexes, or multiple buildings on one parcel), each structure may qualify for its own set of interior ADUs. That means:

You may be able to add significantly more than 11 total ADUs.

Why You Need to Act Fast

While SB 1211 is currently law, it may be amended, restricted, or repealed as local jurisdictions push back or the housing crisis evolves. Getting your plans submitted early locks in your rights, even if the rules change later.

Turning SB 1211 Into Real Units: Our End-to-End ADU Process

We’re a California-based architecture and construction team with deep experience helping multifamily property owners add ADUs under current laws. From early feasibility to final construction, we guide each step of the process—so you can move forward with clarity and confidence.

Step 1: ADU Feasibility & Site Evaluation

Zoning and code compliance review
Lot size, parking, setbacks, and circulation analysis
Maximum ADU count projection with layout options

Step 2: Architecture & 3D Design

Smart layouts to maximize rentable square footage
Conceptual diagrams, massing studies, and renderings
Pre-permit visualization for owner or investor approval

Step 3: Construction Documents

Full permit-ready drawing sets
Structural, MEP, ADA, and Title 24 coordination
Fire, egress, energy, and sustainability compliance

Step 4: Engineering & Budgeting

Structural and civil engineering for detached and converted units
Value engineering to reduce cost
Cost breakdowns and ROI projections

Step 5: Permitting & City Navigation

LADBS, Planning, Fire, and Public Works coordination
Pre-submittal meetings, plan check responses
Keep your ADU count compliant with both SB 1211 and local codes

Step 6: Construction by DRAMS Construction

We’re a California licensed general contractor with experience building both detached ADUs and interior conversions:

Transparent bids and contract terms
Dedicated project management
Efficient build timeline with milestone tracking

Documents That Help You Start Faster

We recommend having:

A recent land survey
A soil (geotechnical) report

If you don’t have them, we’ll refer you to trusted consultants.

Start Now—Before SB 1211 Changes

The opportunity to add multiple units by-right without triggering variances or zoning hearings is rare—and it won’t be around forever. The sooner you act, the more you can build under the current law.

Book Your Free ADU Feasibility Call

DRAMS Architects and Construction help you unlock SB 1211 from start to finish—serving clients throughout California from our offices in Los Angeles and San Francisco.

Architecture. Permits. Construction. All under one roof.

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