Thinking about adding an accessory dwelling unit to your Morgan Hill property? You’re not alone. Many local homeowners want flexible space for family, a future caregiver, or steady rental income, but the rules can feel confusing. In this guide, you’ll get a clear overview of California’s ADU basics, how Morgan Hill typically applies them, what to budget for, and a step-by-step checklist to move from idea to permit. Let’s dive in.
ADU basics in California
California has set a strong baseline that makes ADUs broadly permissible. Cities like Morgan Hill must follow these statewide rules and can add only objective standards that do not block ADUs.
Types of ADUs you can build
- Detached ADU: A separate backyard unit or cottage.
- Attached ADU: Connected to your main home or added onto it.
- Conversion ADU: Created from existing space like a garage or part of the house.
- Junior ADU (JADU): A smaller unit carved out within the existing home.
For a high-level primer on what the state allows, explore the California Department of Housing and Community Development’s ADU guidance. You can find it by visiting the HCD site and reviewing the ADU pages at the California Department of Housing and Community Development.
Statewide protections that help you build
- Ministerial approval: Cities must process complete ADU applications without a public hearing and within state timelines.
- Reasonable standards: Local rules for setbacks, height, and design must be objective and consistent with state law.
- Parking limits: In many cases, cities cannot require additional parking for ADUs, especially for conversions or homes near transit.
- Owner-occupancy: State law has eased many owner-occupancy rules for new ADUs. Check what applies to your situation before you plan.
- Fees and utilities: California law limits certain impact fees for smaller ADUs, and jurisdictions can require reasonable utility connection fees. Exact amounts vary by city and utility providers.
For statewide context and policy insights, the Terner Center for Housing Innovation at UC Berkeley offers research and summaries that explain how these rules work in practice.
How Morgan Hill applies the rules
Morgan Hill implements state law through its Planning and Building divisions. The city can add objective local standards on size, height, placement, and design, as long as they align with the state baseline.
Where local standards apply
- Zoning and eligibility: ADUs are typically allowed in single-family zones and often in some multi-family zones. Always confirm your property’s zoning on the city’s official site.
- Size and height: The city may set maximum square footage or height for detached and attached ADUs and identify how square footage is measured.
- Setbacks and lot coverage: Expect objective standards for side and rear yard setbacks and overall lot coverage. These are usually more flexible for ADUs than for full-size homes.
Because numeric limits can change, it is smart to confirm the latest standards by searching the City of Morgan Hill’s site for “Accessory Dwelling Unit” and “Planning Division.”
Parking, occupancy, and utilities
- Parking: Morgan Hill follows state limits. You may be required to provide one on-site space only in specific cases. Exemptions often apply for ADUs created within existing space or near transit.
- Owner-occupancy: Many local owner-occupancy rules for new ADUs have been phased out under state law. Confirm what Morgan Hill requires for your property.
- Utilities and fees: Plan for water and sewer connection review. Some fees may be prorated or limited for smaller ADUs, but you should verify current schedules with the city or service provider.
Design review and safety
- Objective design: Materials, rooflines, windows, and exterior features may need to meet objective standards to match neighborhood patterns. These standards are applied without discretion.
- Fire and access: The Fire Department can require clearances, driveway access, and other safety measures. Ask early about any fire-related requirements.
HOAs and CC&Rs
Your city permit does not change private covenants. Homeowner associations and recorded CC&Rs can restrict ADUs. Review your governing documents and seek legal advice if needed.
Costs, value, and rental outlook in the South Bay
ADUs can be a smart long-term decision, but plan for Bay Area costs and timelines. With the right design and construction approach, you can create useful space and potential income.
Typical forms and tradeoffs
- Detached ADU: Highest privacy and rental appeal, often higher cost per square foot.
- Attached ADU: Good middle ground on cost and convenience, with easier utility tie-ins.
- JADU: Usually the least expensive option, often up to about 500 square feet with shared facilities.
- Garage conversion: Can be cost-effective since the structure exists. Always confirm conversion standards with the city before drawing plans.
Cost drivers to budget
- Site and structure: Foundation work, grading, retaining walls, and drainage.
- Utilities: Service capacity, trenching, and potential meter or panel upgrades.
- Design and compliance: Architect fees, engineering, and plan check responses.
- Access and safety: Driveway adjustments, fire access, and egress.
Financing options
Many homeowners evaluate cash, a cash-out refinance, construction loans, or specialized ADU financing programs. Review options with a lender familiar with local ADUs so you understand draw schedules and appraisal considerations.
Value, rent, and taxes
- Property value: An ADU increases usable living area and the potential for income, which can improve resale value when done thoughtfully.
- Rental income: Rents depend on size, finishes, and current local demand. Many owners choose long-term tenants for stability and straightforward insurance.
- Taxes and assessment: An ADU can affect your property’s assessed value. For county-level guidance and related contacts, start with the Santa Clara County official site and review assessor resources.
Step-by-step checklist for Morgan Hill homeowners
Follow this local checklist to reduce surprises and keep your project moving.
Preliminary steps
- Confirm zoning and parcel eligibility. Search the city’s official site for “Morgan Hill zoning map” and “Accessory Dwelling Unit.”
- Review the municipal code and objective standards, including size, height, setbacks, lot coverage, and design.
- Check HOA and CC&Rs. Request approvals or legal guidance if your community has restrictions.
- Confirm utilities. Contact the City’s Building or Utilities departments about water and sewer capacity and connection fees.
- If not on city systems, check septic or well feasibility with Santa Clara County Environmental Health.
Design and pre-permit
- Select your ADU type and sketch rough plans that fit your lot and goals.
- Consult the Fire Department about access and any defensible space requirements.
- Get preliminary estimates from local architects and ADU-experienced contractors.
Permit application and approvals
- Prepare and submit a complete application to Planning and Building. Include a site plan, floor plans, elevations, and utility plans.
- Respond quickly to completeness checks and plan-review comments.
- Record any required documents, such as easements or deed restrictions, if the city requires them.
Construction and occupancy
- Obtain building permits, schedule inspections, and address corrections promptly.
- Secure a certificate of occupancy or final permit approval before using or renting the unit.
After you move in or rent
- Update records for tax reporting and, if renting, comply with local rental rules or licenses.
For background on state rules throughout this process, review the HCD’s ADU guidance at the California Department of Housing and Community Development and policy research from the Terner Center for Housing Innovation.
Common pitfalls to avoid
- Skipping early zoning checks. Confirm your lot’s eligibility and basic standards before spending on design.
- Underestimating utilities. Connection capacity, trenching, and panel upgrades can add cost and time.
- Overlooking fire access. Driveway width and clearances can affect site layout and approvals.
- Ignoring CC&Rs. Private covenants can restrict ADUs. Read them before you apply.
- Designing before budgeting. Align size and finishes with total cost and expected rent or family use.
Resources to verify your plan
- California ADU rules and homeowner guidance: California Department of Housing and Community Development.
- Policy research and case studies: Terner Center for Housing Innovation.
- County-level links for assessor, planning, and environmental health: Santa Clara County official site.
- City-level standards and checklists: Search the City of Morgan Hill site for “Accessory Dwelling Unit,” “Planning Division,” and “Building Permits.”
Ready to plan your ADU?
If you want help aligning your ADU plan with resale goals, rental potential, or timing a move, I’m here to advise. I can connect you with local architects, contractors, and lenders who understand Morgan Hill’s process, then help you position your property for long-term value. When the time is right, we can market your home’s new flexibility to the right buyers and tenants.
Reach out to discuss your property and goals with Erica Trinchero.
FAQs
How large can an ADU be in Morgan Hill?
- Morgan Hill sets objective size limits by ADU type. Check the municipal code or request a pre-application review with Planning to confirm current square footage caps and measurement methods.
Do I need to provide extra parking for an ADU in Morgan Hill?
- Parking rules are limited under state law. You may need one space only in specific cases, with common exemptions for conversions or locations near transit. Confirm your parcel’s requirements with the city.
How long does the ADU permit take in Morgan Hill?
- ADU permits are processed ministerially once your application is complete and must meet state timelines. Ask Planning and Building for current average processing times and how to submit a complete package.
Will I have to live in the main home if I build an ADU in Morgan Hill?
- State law has eased many owner-occupancy requirements for new ADUs, but details vary. Verify whether any owner-occupancy rules apply to your property with Morgan Hill Planning.
Can my HOA stop me from building an ADU in Morgan Hill?
- City permits do not override private covenants. Review your HOA’s CC&Rs, as private rules may restrict ADUs, and seek legal guidance if needed.
Will an ADU change my property taxes in Morgan Hill?
- An ADU can affect your assessment. For county guidance and next steps, start with resources available through the Santa Clara County official site and consult the Assessor’s office as needed.
