Thinking about adding a second front door or splitting a large Los Gatos lot to unlock more value? California’s SB 9 opened two clear, ministerial paths to create housing on single‑family parcels, but the rules on the ground still matter. You want a practical playbook that shows what is allowed, what to check first, and how to move from idea to income without surprises. This primer gives you a local, investor‑friendly overview so you can evaluate opportunities with confidence. Let’s dive in.
SB 9 basics in Los Gatos
SB 9, effective January 1, 2022, created two ministerial approvals on single‑family‑zoned parcels: a two‑unit path and a ministerial lot split. Ministerial means your project is reviewed against objective, numeric standards rather than subjective design opinions or public hearings. If you meet the rules, the Town must process the permit.
SB 9 does not override every local control. Objective standards in Los Gatos still apply, including height, setbacks, floor area, tree protection, hillside limits, fire safety, and stormwater rules. The statute also contains exclusions, such as certain historic resources. Always confirm parcel‑specific eligibility with Los Gatos Planning.
The two‑unit path: how it works
What you can build
Under SB 9’s two‑unit path, you can create up to two residential units on a single‑family parcel. You might convert an existing home into two units, add a second principal unit alongside the existing house, or build a new two‑unit structure if the lot and envelope allow it.
Common local use cases
Investors often add a second principal unit to boost rental income, convert a larger single‑family home into two units, or combine a modest remodel with a new attached companion unit. Parcels with reasonable width, depth, and gentle slopes tend to pencil best in Los Gatos where hillside and tree rules are common.
Key constraints to check
- Objective standards for height, setbacks, lot coverage, and floor area. These rules define the buildable envelope.
- Replacement and tenant protections if demolition is involved. Confirm any replacement obligations before planning a teardown.
- Private covenants and easements. HOA CC&Rs and recorded restrictions can block multi‑unit conversions even if SB 9 would otherwise allow them.
- Utilities. Separate sewer and water service, capacity, and connection feasibility are essential for two lawful dwellings.
- Parking, drainage, and stormwater requirements. These are objective but can shape site design and cost.
Expected outcomes
The two‑unit path can raise rental yield, improve exit options for resale, and enhance flexibility for multigenerational living. In many Los Gatos neighborhoods, privacy, scale, and parking will drive design choices. Projects that fit the established pattern of development typically face fewer technical hurdles.
SB 9 lot split: what to expect
Mechanics and eligibility
The SB 9 lot split allows a qualifying single‑family parcel to be split into two legal lots through a ministerial map process. You must meet statutory size and configuration rules and any local objective standards that apply to parcel width, frontage, access, and services.
After the split is recorded, you can pursue per‑lot construction subject to objective standards. In some scenarios, combining the lot split with the two‑unit path can result in up to four units total. Local rules and parcel constraints can limit that theoretical maximum.
Investor use cases
- Acquire a larger parcel, split it, and build one home per lot.
- Develop both lots for rental income or for sale.
- Retain one lot and sell the other to de‑risk the project or recapitalize construction.
Los Gatos checks that matter
- Recent subdivisions and affordability protections can limit eligibility.
- Frontage improvements, curb cuts, sidewalks, and utility separations can be required as objective conditions.
- Slope, grading, and geotechnical constraints are common in hillside areas and can drive both design and cost.
What “ministerial” means locally
Objective standards, not hearings
Ministerial review uses measurable rules, not subjective design opinions. If your drawings meet the numeric standards, the Town processes the permit without discretionary hearings.
Standards you will see
- Maximum height and number of stories
- Front, side, and rear setbacks
- Lot coverage and floor area ratio
- Building envelope limits on sloped lots, including cut and fill caps
- Privacy and window placement rules expressed in measurable terms
- Parking counts or objective parking exemptions near transit, where adopted
- Landscaping, tree protection, and any required replacements
- Fire safety and defensible space in wildfire areas
- Stormwater treatment and site drainage controls
Los Gatos‑specific considerations
Los Gatos has hillside neighborhoods and combining districts with geotechnical and grading requirements. The Town maintains tree protections that can affect site planning and timing. Historic resources are treated carefully, and parcels in or near historic districts may be excluded or handled differently under SB 9. Utility and frontage upgrades can be triggered by a lot split or new principal unit.
Due diligence checklist
Work through this checklist before you buy or apply.
- Title and CC&Rs. Identify HOA covenants or private restrictions that prohibit multi‑unit use or lot splits.
- Historic and conservation status. Check local historic inventories and any conservation easements.
- Zoning and General Plan. Confirm the parcel’s single‑family status and Los Gatos’ SB 9 applicability for that site.
- Parcel size, shape, and slope. Map topography and identify hillside overlays or geologic hazard areas.
- Trees. Inventory protected species and size thresholds. Factor mitigation or removal permits into your plan.
- Utilities and sewer capacity. Locate laterals, confirm separate service feasibility, and verify connection fees.
- Access and frontage. Evaluate driveway access, frontage width, and curb cut limits. Shared driveways can complicate splits.
- Easements and rights‑of‑way. Confirm private and public constraints that limit building envelopes or access.
- Wildfire and environmental. Review fire hazard zones, FEMA flood maps, and debris flow areas that can trigger added requirements.
- Permitting history. Check for recent SB 9 activity, prior violations, or open permits.
- Cost plan. Estimate entitlement and permit fees, tree mitigation, grading and geotech, utility connections, frontage improvements, and any tenant‑related obligations.
- Market analysis. Review rents and sale comps for small multi‑unit properties and duplexes in Los Gatos and nearby markets. Consider how neighborhood character could influence resale.
Timelines you can actually use
SB 9 avoids discretionary hearings, but it still requires careful preparation and plan checks. Typical ranges look like this.
- Pre‑purchase due diligence: 1 to 4 weeks
- Application preparation, surveys, plans, and studies: 2 to 8 weeks, longer if geotechnical work is needed
- Ministerial SB 9 review or lot split processing: about 30 to 120 days after a complete submittal
- Building permit plan check: 4 to 16 weeks, often overlapping with final ministerial sign‑off for simple projects
- Construction: 4 to 9 months for small duplex or addition projects, 9 to 18+ months for full builds with grading on slopes
- Total from purchase to occupancy: 6 to 24 months depending on complexity
- Financing lead time: confirm construction or permanent financing terms, covenants, and draw schedules early
Risks and how to manage them
- Private restrictions. HOA CC&Rs and easements can block SB 9 outcomes. Resolve early or move on.
- Hillside and tree constraints. Expect added studies, retaining walls, and mitigation. Build contingency into budget and time.
- Utility separation costs. New or split sewer and water laterals can be material. Verify locations and fees before design.
- Historic resource exclusions. A parcel may appear eligible but be in a historic area. Confirm with Planning before you invest.
- Neighborhood pushback. SB 9 limits discretionary review, but opposition can surface other requirements. Design with privacy, parking, and scale in mind.
- Finance and insurance. Some lenders restrict nonstandard conversions. Wildfire zones can raise insurance costs. Shop terms early.
- Resale fit. Some buyers prefer single‑family character. Weigh rental yield against potential resale perceptions.
Making SB 9 work in Los Gatos
A successful SB 9 project blends compliance with objective standards and a design that respects neighborhood scale and privacy. Start with a clean title review, a site walk focused on slope and trees, and a quick call with Los Gatos Planning to confirm feasibility. Line up a land surveyor, civil and geotechnical engineers, and an experienced architect who knows how the Town applies SB 9 checklists.
If you are weighing parcels or comparing hold‑versus‑split strategies, you want local comps and realistic rent assumptions. The Brian Flack Team pairs hometown insight with data‑driven analysis so you can choose the right site, set the right timeline, and plan for the costs that matter. Ready to explore SB 9 opportunities or assess your current property’s potential? Get your instant home valuation and let’s talk about next steps.
FAQs
What is SB 9 and how does it apply in Los Gatos?
- SB 9 creates ministerial approvals for up to two units on a single‑family parcel and allows a ministerial lot split, subject to objective standards and statutory exclusions that Los Gatos applies through its local rules.
Can I build four units on a single Los Gatos parcel using SB 9?
- In some cases, combining a lot split with the two‑unit path can yield up to four units, but local objective standards, parcel constraints, and statutory limits can reduce that maximum.
How long does an SB 9 lot split usually take in Los Gatos?
- After you submit a complete application, ministerial lot split processing commonly ranges from about 30 to 120 days, followed by building permit plan checks that can take 4 to 16 weeks.
Do HOA rules or private covenants affect SB 9 projects?
- Yes, private CC&Rs and easements can prohibit multi‑unit conversions or block lot splits, and SB 9 does not override lawful private restrictions.
What are the biggest cost drivers for SB 9 projects in Los Gatos?
- Utility separations, tree mitigation, grading and geotechnical work on hillsides, required frontage improvements, and building permit fees are frequent cost drivers to plan for.
