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Call (916) 436-3776Build an ADU California
How Do I Build an ADU in California and Pay for It in 2026?
Building an ADU in California typically costs $150 to $400 per square foot, most projects run $180,000 to $360,000, and you pay for it with home equity, a renovation loan, or a construction loan. California's 2026 rules help: a CalHFA grant of up to $40,000 covers predevelopment costs, SB 937 lets you defer most impact fees until final inspection, and units under 750 sq ft are exempt from most impact and school fees. With metro rents of $1,500 to $3,500 a month, a well-planned ADU often returns 8 to 12% a year. Ashlar Lending arranges the financing; Serve First values the result.
Building an accessory dwelling unit (ADU) can add income, house family, and lift your property's value, but it's mostly a financing and permitting project. California's 2026 rules are the most ADU-friendly in the nation: 60-day approval timelines, pre-approved plans, no owner-occupancy on standard units, a state grant of up to $40,000 for predevelopment costs, and a law letting you defer most impact fees until final inspection. This guide walks through what an ADU costs, how to pay for it, and how to make the rent cover the payment, then links to a guide for your area. Ashlar Lending arranges the financing; Serve First tells you what it adds to your home's value.
One family. Financing, property, and paperwork.
Fund the build, and make the numbers work
Building an ADU is largely a financing project. The Ashlar Brands family helps you pay for it and put it to work:
- Ashlar Lending Inc. (NMLS #2699657) can arrange construction or renovation financing to build your ADU, tapping home equity, a renovation loan, or a construction loan, and can model the rent-vs-payment math so the project pencils. We can also point you to programs like the state’s CalHFA ADU grant.
- Serve First Realty can tell you how much an ADU will add to your property’s value and rentability, useful before you spend, and essential if you may sell later.
- Ashlar LDA, Inc., a bonded and registered Legal Document Assistant, can prepare related deeds and documents at your direction.
These are separate businesses in the Ashlar Brands family. Serve First is a real estate brokerage, not a lender or contractor; loan terms are set by the lender and construction is performed by your licensed contractor. A Legal Document Assistant prepares documents at your direction and is not a substitute for an attorney.
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