ADU Company in Mentone, CA
Mentone is one of the more interesting places in the Inland Empire to build an accessory dwelling unit, because the lots are big enough to actually do it and the permit path runs through San Bernardino County, not a city hall. We’re Lodgewick ADU Builders, the ADU company of the Kingswell family. Every project we take on in Mentone starts with a written price before any work begins. If you’re wondering whether your half-acre lot can hold a detached ADU or whether your garage conversion will clear County requirements, call (254) 602-5618 and we’ll walk you through it.
Why Mentone Homes Are Different
Mentone grew up as a citrus-belt community, and the housing stock still reflects that. Most homes are mid-century ranch houses and older bungalows sitting on lots that run a half-acre or more, sometimes much more. That’s good news for a detached ADU, because there’s actual room to build one without crowding the main house. The tradeoff is what’s underneath and behind those older homes: electrical panels sized for 1960s demand, galvanized supply lines, and a meaningful number of private septic systems instead of public sewer. Any of those can add scope to an ADU project, and we’ll tell you before you’re surprised by it.
Mentone sits at the transition from valley floor to foothills, which does two things. First, summer temperatures regularly climb past 105°F, so HVAC sizing and attic insulation in an ADU matter more here than they do ten miles downhill. Second, the Santa Ana wind corridor pushes through this area, and many parcels fall within a High Fire Hazard Severity Zone. That triggers Chapter 7A fire-resistive construction requirements on exterior materials, vents, and glazing, which adds real cost to a build compared to lower-valley neighbors. We plan for that from the first site visit, not after the permit review comes back.
Our Main Mentone Services
Most Mentone homeowners come to us for one of three things: room to grow without moving, a use for a garage that hasn’t held a car in years, or a full second home in the back yard. Each service has its own Mentone page with local pricing and details.
Home Addition Contractor in Mentone
A home addition in Mentone means working around existing ranch-home layouts and, often, bringing the electrical service and septic system along with the new square footage. We handle the full scope: foundation, framing, roofing, mechanicals, and finish work, with the County permit pulled before we start. The Kingswell Guarantee means a written price, a real arrival window, and a clean job site while we’re on your property. See what a Mentone addition involves, including local cost ranges, on the Home Addition Contractor in Mentone page.
Garage Conversion Contractor in Mentone
Converting a garage in Mentone usually means converting an attached garage on an older ranch home, which brings its own set of questions: is the slab sound, does the electrical panel have room for a new circuit, and will the County require fire-rated separation between the new living space and the rest of the house? We answer those with a written scope of work and a fixed price before anything gets torn out. For a full breakdown of what a Mentone garage conversion costs and how the septic evaluation fits in, visit the Garage Conversion Contractor in Mentone page.
ADU Builders in Mentone
Mentone’s large lots make it one of the better places in the region for a detached ADU, and we build them from the ground up or as prefab units placed on a prepared foundation and tied into utilities. The County’s septic adequacy evaluation is a step many homeowners don’t know about until it hits the timeline, and we handle it as part of the permit package. If you want a back-yard home with a written guarantee and a price that doesn’t move after you sign, start with the ADU Builders in Mentone page.
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 Mentone
We work with established ADU and materials brands including Abodu, Cover, and Dvele for prefab builds, and James Hardie for fire-rated siding that meets Chapter 7A requirements on Mentone’s hillside-adjacent parcels. Parts and finishes are ordered through our Inland Empire supply network, which keeps most projects moving without weeks of waiting. See the full range on our brands page.
Pricing for ADU Company in Mentone, CA
Here are the ranges we typically see for Mentone jobs. These are ballpark figures; your written quote depends on your specific lot, the septic evaluation, and fire-zone requirements.
| Service | Typical range in Mentone |
|---|---|
| Detached ADU (new build, 400 – 800 sq ft) | $180,000 – $420,000 |
| Prefab ADU (foundation, utility tie-in, finish) | $150,000 – $320,000 |
| Garage conversion to ADU | $95,000 – $190,000 |
| Junior ADU (interior conversion within existing home) | $60,000 – $130,000 |
| Home addition (400 – 800 sq ft ground-up) | $140,000 – $330,000 |
| Fire-resistive upgrades (Chapter 7A siding, vents, glazing) | $8,000 – $35,000 |
| Electrical panel upgrade (100A to 200A) | $2,500 – $6,000 |
| Septic adequacy evaluation and system upgrade (if required) | $1,500 – $30,000 |
| HVAC sizing and installation for ADU | $7,000 – $18,000 |
| Attic insulation upgrade to meet current code | $2,000 – $6,500 |
What pushes Mentone pricing upward is the combination of fire-zone material requirements and older infrastructure. A home in the flat citrus-belt section with a modern panel and public sewer will land toward the low end; a hillside-adjacent parcel on septic with a 1960s electrical service will land higher. Whatever the number is, we put it in writing before work starts and it does not change at the door.
Neighborhoods We Serve in Mentone
We work across Mentone’s residential areas, from the older ranch-home streets near the old citrus packing districts up to the foothill-adjacent parcels where fire-zone rules kick in. We schedule site visits across the area within a few business days of your call.
- Mentone downtown corridor and surrounding ranch-home streets
- Parcels east toward Greenspot Road and the Santa Ana wash
- Foothill-adjacent lots along the Highway 38 approach
- Semi-rural acreage south of the rail line
- Neighborhoods near Crafton and the Redlands boundary
Service Area – Cities Near Mentone
While this page focuses on Mentone, our crews also handle ADU and addition work in nearby Inland Empire communities. You can find city-specific pricing and permit notes for Redlands, CA, Yucaipa, CA, Highland, CA, and Calimesa, CA on their own pages.
Serving Mentone, CA - Our Local Coverage Area
We’re based in the Mentone 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 Mentone
Because Mentone is unincorporated, permits go through San Bernardino County Land Use Services rather than a city building department. You can generally expect the County review to take longer than a city review, and the septic adequacy evaluation, if your parcel requires one, adds weeks on top of that. We handle the submittal and tracking as part of your project.
Many Mentone parcels, especially those toward the foothills, fall within a High Fire Hazard Severity Zone that triggers Chapter 7A fire-resistive construction. That affects exterior siding, vents, windows, and some decking. We check your specific parcel’s designation before quoting so the price reflects what the County will actually require.
Yes. If your Mentone property is on a private septic system, San Bernardino County requires an adequacy evaluation before it will approve an ADU that adds new dwelling-unit load. We coordinate that evaluation and include any required system upgrades in your written quote up front. Call (254) 602-5618 and we’ll help you figure out whether your parcel needs it.
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 Mentone Customers Say
"Junior ADU conversion inside the house. They protected the rest of our place with plastic and daily cleanup. Done nearly on schedule and on the number they quoted."
- Sabrina Veld"Garage conversion into an office and guest room. Fair written price, finished close to on schedule, and they fixed a small drywall crack under warranty months later without any hassle."
- Diana Cho"The ADU came out beautiful and the permitting, which terrified me, was handled start to finish. They kept me updated every week so I was never wondering what was happening."
- Shauna Mills