- Typical cost
- Varies by parcel, unit count and site work
- Typical timeline
- 12–24 months including entitlement and permitting
- Permits through
- LADBS
- Service area
- Brentwood, Westside
What SB9 Allows
Two paths, sometimes combined: splitting one parcel into two, or building a second unit on the existing parcel. Both are ministerial approvals when the criteria are met.
- Urban lot splits into two parcels
- Two-unit developments on a single parcel
- New duplexes and detached second homes
- Combining SB9 with an ADU where allowed
- Tear-down and rebuild scenarios
SB9 Lot Splits & Two-Unit Development Conditions in Brentwood
On hillside lots, delivery and staging are genuine planning items: concrete pumps, crane picks and material drops all have to be sequenced around streets that cannot hold two trucks. Grading review, geotechnical reports and retaining work are normal scope here. Homes are largely 1930s through 1960s, so a remodel of any depth touches wiring, plumbing and HVAC.
- Narrow hillside streets that limit deliveries and require staged logistics
- Grading review, geotechnical reports and engineered foundations
- Retaining walls and drainage as part of the base scope
- 1930s to 1960s homes needing full rewire, replumb and new HVAC
- Higher finish allowances, which changes cost per foot rather than structure
Eligibility Comes First
A lot has to be in a single-family zone, meet minimum size after the split, and sit outside certain hazard and historic categories. Recent rental or eviction history can also disqualify a property. We check all of it before you spend money on design.
- Zoning and parcel size verification
- Fire-severity, flood and hazard zone screening
- Historic district and HPOZ constraints
- Rental and eviction history review
- Owner-occupancy and deed restriction requirements
From Parcel Map to Keys
SB9 projects involve a survey, a parcel map, utility separation, and then a full building permit for each unit. Because we design and build, one team carries it from the eligibility letter through the final inspection.
- Survey and tentative parcel map
- Separate utility services and meters
- Architectural plans and structural engineering
- Plan check corrections handled by us
- Construction with our own crews
FREQUENTLY ASKED QUESTIONS
Do you do sb9 lot splits & two-unit development in Brentwood?
Yes. Brentwood is part of our regular service area. We'll come out for a free on-site consultation, walk the property, and tell you what's realistic before you spend anything on design.
What does sb9 lot splits cost in Brentwood?
Varies by parcel, unit count and site work. Site conditions in Brentwood and your material selections move the number, which is why we price after walking the property rather than over the phone.
Who issues the permit in Brentwood?
Permits for this work go through LADBS. We handle the submittal, plan check corrections and inspections as part of the project.
Does my lot qualify for an SB9 split?
It has to be in a single-family zone, be large enough that both resulting parcels meet the minimum, and avoid certain hazard, historic and rental-history disqualifiers. We run the eligibility review before any design work.
How long does an SB9 project take?
Plan on 12 to 24 months from eligibility review to finished units, with the parcel map and plan check often taking as long as construction.
Can I build an ADU on an SB9 lot?
Sometimes, depending on the path you take and your city's implementation. We map out the maximum unit count for your parcel up front so you can compare options.
Do you handle SB9 projects near me outside the City of Los Angeles?
Yes. SB9 is state law, so it applies across California, but every city implements it differently. We handle SB9 lot splits and two-unit developments throughout the greater LA area within about 100 miles of our Woodland Hills office.
Similar Projects We've Built
SB9 Lot Split with Two New Homes, Highland Park
A single 6,800 sq ft Highland Park lot split under SB9 into two parcels, each with a new two-story detached home.
SB9 Lot Split with Two New Homes, Fullerton
A 9,000 sq ft Fullerton lot split under SB9 into two parcels, each with a new two-story modern farmhouse.
SB9 Lot Split with Two New Homes, Newbury Park
A 10,000 sq ft suburban lot split under SB9 into two parcels, each with a new single-story contemporary ranch.
DISCUSS YOUR PROJECT WITH 1 SMART BUILD
Licensed, bonded and insured design-build general contractor serving Los Angeles County and Southern California. Tell us about your property and goals, and we'll walk you through feasibility, permitting and a clear plan.