Detached units, garage conversions, and in-law suites — designed, permitted, and built by one licensed local team from first sketch to keys.
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KHB Construction designs, permits, and builds accessory dwelling units across the Central Valley — Modesto, Stockton, Ripon, Manteca, Tracy, and Turlock. As a licensed design-build general contractor (CSLB #1070537), we handle the entire ADU path in one contract: feasibility on your actual lot, unit design, structural and Title 24 documents, city submittal under California’s 60-day ADU review clock, and construction through final inspection and occupancy.
Whether it’s rental income, a place for parents, or space for an adult kid saving for their own home, an ADU is the highest-leverage square footage you can add in California right now — and the Central Valley’s lot sizes make it especially practical here.
Last updated: June 2026 · Reviewed by the KHB Construction team
Every unit is designed for its actual purpose — a rental pencils differently than a parent suite, and the design should reflect which one you’re building.
Small footprint, complete home. A modern detached ADU concept.
State law has systematically cleared the obstacles that used to kill ADU projects. Cities must review conforming ADU applications ministerially — no discretionary hearings — and act within 60 days. Setbacks for new detached units are capped at four feet on side and rear. Cities can’t require owner-occupancy on most new ADUs, and units under 750 sq ft are exempt from impact fees. Several local jurisdictions sweeten the deal further: Turlock, for example, maintains pre-approved ADU plan sets that cut review time dramatically.
The catch: those protections apply to conforming applications. Setback lines, lot coverage, utility routing, and fire separation drawn wrong put you back in correction purgatory. That’s the part we get right the first time — see our plans and permits service for how we run submittals in every local jurisdiction.
Realistic 2026 numbers for our service area: garage conversions typically start in the low six figures; detached new-construction units run higher depending on size, finish level, and utility distances. Against that, Central Valley ADU rents commonly run from the mid-$1,000s to mid-$2,000s monthly depending on city and unit size — and the unit adds appraised value to the property permanently.
In our design phase we price your specific unit on your specific lot — utility runs, site work, and finishes included — so the investment math is real before you commit to anything.
Built like a home, because it is one. KHB construction in progress.
1. Lot feasibility. Setbacks, lot coverage, utility locations, and access on your actual parcel — before you spend on design.
2. Design & budget. The unit designed for its purpose, priced as it develops by our in-house design team.
3. Permits. A conforming application filed with your city under the 60-day clock — our specialty across Modesto, Stockton, Turlock, and every local jurisdiction.
4. Construction. Foundation to final inspection with a dedicated project manager and published schedule.
5. Occupancy. Certificate issued, keys handed over — rental-ready or family-ready.
On most single-family lots in California, yes — state law requires cities to allow at least one ADU (and often a JADU too) on residential parcels. The real questions are placement, utility routing, and budget, which is exactly what our feasibility step answers for your specific property.
State law protects at least 800 sq ft; detached units typically range up to 1,200 sq ft depending on local standards and lot coverage. JADUs cap at 500 sq ft within the existing home. We design to what your lot and city actually allow.
Typically 2–4 months for design and permits (the state’s 60-day review clock helps once a conforming application is in), then 4–7 months of construction depending on type — garage conversions fastest, detached new construction longest.
Garage conversions generally start in the low six figures; detached units run higher with size and site conditions. We fix the price during design — utilities, site work, and finishes included — so there’s no estimate-to-invoice drift.
Usually not required for units under 750 sq ft (cities can’t demand new connections or impact fees for them in most cases), but separate metering can make sense for rentals. We design the utility strategy around how you’ll use the unit.
Yes — where cities offer them (Turlock’s program is the local standout), pre-approved sets can cut review time dramatically. We’ll tell you honestly whether a pre-approved or custom design fits your lot and goals better.
Start with a feasibility conversation — setbacks, utilities, budget, and honest numbers on what your property can carry.
Or call (209) 528-0255 · CSLB #1070537
