







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Rialto, CA
Lodgewick ADU Riverside builds accessory dwelling units (ADUs, or small second homes on your existing lot), garage conversions, and home additions in Rialto. Rialto’s mix of 1950s – 1970s ranch homes on 7,000+ sq ft lots makes it one of the easier Inland Empire cities for a detached ADU or garage conversion, but the hot, dry summers and Santa Ana winds change how we think about materials and cooling. Whether you’re pricing a backyard unit or a room addition, call us at (831) 292-4191 for a written estimate.
Why Rialto Homes Are Different

Most Rialto homes are single-story tract builds from the post-war decades: wood-frame construction, stucco exteriors, concrete slab foundations. That’s good news for ADU work. Slab foundations mean we’re not cutting through a basement or crawl space, and the deep backyards common on Rialto lots give us real room to position a detached unit without crowding the main house.
The climate shapes the build. Rialto summers run hot and dry, and Santa Ana winds push dust and embers across the Inland Empire. For detached ADUs, we lean toward fire-resistant siding options like James Hardie fiber cement, and we pay close attention to passive cooling: window placement, roof overhangs, and insulation that keeps a small unit livable in August without running the AC nonstop. Winters are mild, so heavy insulation isn’t the priority here, but tight air sealing matters because dust gets into everything during wind season.
On the east side of Rialto, near the old citrus groves, you’ll still find homes with original detached two-car garages set back on long driveways. Those conversions are often the fastest path to an ADU in Rialto because the setback is already solved and the structure is already there.
Our Main Rialto Services
Rialto homeowners call us most about two things: adding square footage to the existing house and converting underused garage space into livable square footage. Here’s how each works in Rialto specifically.
Home Addition Contractor in Rialto
Room additions in Rialto usually mean building out from the back of a ranch home or adding a second-story bump-out over the garage. The concrete slab foundations on older Rialto homes are generally in decent shape, but we always check the footing depth before framing because some 1950s builds were poured thinner than today’s code allows. Santa Ana wind season also affects framing schedules, so we plan exterior work around the windiest weeks. Home Addition Contractor in Rialto page has the full scope.

Garage Conversion Contractor in Rialto
A garage conversion turns an attached or detached garage into a studio, bedroom suite, or home office. In Rialto, the single-car attached garages on post-war tract homes convert well because they already share a wall and roofline with the house. Detached garages on the east side, near the old citrus groves, are even simpler: the structure is already there, and many sit far enough from property lines to meet setback rules without variances. Garage Conversion Contractor in Rialto page covers the process.

ADU Builders in Rialto
Detached ADUs in Rialto work especially well on the 7,000+ sq ft lots common across the city. There’s room for a 600 – 1,000 sq ft backyard unit without sacrificing the yard the family already uses. We match each lot to the right build method: prefab units from brands like Boxabl and Dvele for faster timelines, or site-built for irregular lot shapes and custom layouts. ADU Builders in Rialto page has the details.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Brands We Service in Rialto
We work with established prefab ADU manufacturers including Dvele, Boxabl, and Cover, plus James Hardie siding for fire-resistant exteriors that hold up through Rialto’s wind and heat. See our brands page for the full list of what we service and recommend across the Inland Empire.
Pricing for ADU Company in Rialto, CA
Here are the ranges Rialto homeowners typically see for the work we do. These are written-price ranges, not ballpark guesses pulled from another market.
| Service | Typical range in Rialto |
|---|---|
| Detached ADU (prefab, 400 – 600 sq ft) | $180,000 – $265,000 |
| Detached ADU (site-built, 600 – 1,000 sq ft) | $245,000 – $390,000 |
| Garage conversion (attached, studio) | $85,000 – $135,000 |
| Garage conversion (detached, full ADU) | $135,000 – $210,000 |
| Home addition (master suite, 300 – 500 sq ft) | $115,000 – $190,000 |
| Home addition (family room or kitchen bump-out) | $90,000 – $175,000 |
| JADU (converted interior space) | $65,000 – $110,000 |
What pushes prices up in Rialto: older slab foundations needing seismic retrofits, long utility runs from the main panel to a backyard ADU, and fire-resistant material upgrades for homes near the foothill edges of the city. Every estimate is a written line-item price, delivered before any work starts, under The Kingswell Guarantee. That means the number we give you is the number you pay.
Neighborhoods We Serve in Rialto
We work across Rialto, from the older tracts near downtown to the newer developments on the north and east sides. Response time for an estimate visit is generally one to three business days depending on where you are in the city.
- Downtown Rialto
- Las Colinas
- North Rialto
- East Rialto (near the old citrus groves)
- West Rialto
Service Area – Cities Near Rialto
We serve Rialto and the surrounding Inland Empire communities from our Riverside – San Bernardino area office. Crews work locally in Fontana, CA, Riverside, CA, Highland, CA, and Mira Loma, CA, with the same written pricing and 365-Day Done Right Promise on every job.
Serving Rialto, CA - Our Local Coverage Area
We’re based in the Rialto area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About ADU Company in Rialto

Once permits are approved, most Rialto ADU projects begin within two to four weeks. Permit timelines vary by project scope and the city’s current review volume. Call (831) 292-4191 and we’ll give you a realistic schedule for your specific lot.
Most Rialto neighborhoods are not governed by active HOAs, but a few newer subdivisions are. State ADU law overrides many HOA restrictions, though architectural review clauses can still apply. We’ll check your specific situation during the estimate.
It’s our written guarantee on every project: if the work isn’t done right, we come back and make it right within 365 days of completion, at no charge. It’s in writing, on every job, before we start.
Ready to talk about your Rialto property? Call us at (831) 292-4191 for a free, written estimate. A live person answers, day or night.
What happens when you call
- 1A real person answersNo phone trees - talk to a local adu pro.
- 2You get an upfront price rangeHonest numbers before anyone is dispatched. No surprises.
- 3We come out and measureLicensed & insured, at a time that suits you - the visit and the quote are both free.
- 4You get the price in writingLine-itemed, yours to keep, and nothing starts until you say go.
What Rialto Customers Say
"A whole backyard ADU from scratch. Terrified me going in, but they kept me updated weekly and there were no nasty surprises. Quality work and a fair price."
- Noreen Fletcher"Detached unit in the backyard for rental income. They handled design and permits and gave me a real schedule. Came in close to on time and exactly on the written price."
- Benjamin Stahl"Added a suite for my dad. They walked us through every cost before a hammer swung and stuck to it. The written price is what we paid, no change orders."
- Ingrid Salazar





