Kitchen remodeling
Bathroom remodeling
Home additions & ADU
Roofing
Windows & doors
Driveway & pavers
FenceFree written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable General Contractor Across Los Serranos
Finding a General Contractor who actually understands Los Serranos means more than hiring someone with a truck and a license number. It means working with a team that knows 91709 sits in unincorporated San Bernardino County, not the City of Chino Hills, even though Chino Hills wraps around it on every side. That single jurisdictional fact changes which permits you pull, which inspectors sign off, and how long your project takes. Square One Builders has managed full-scope remodels, additions, and ADUs across Los Serranos for years, and we coordinate every trade under one contract so you don’t have to chase separate specialists. Call (877) 688-9930 when you’re ready to talk about your project.
Why Square One Builders Is Los Serranos’s Preferred General Contractor Company
Los Serranos homeowners keep coming back to us for one reason: we know the difference between a county permit and a city permit before we touch a wall. That’s not a small thing here. A contractor who pulls a Chino Hills city permit for a job on the county side of the street creates weeks of delay, and we see that mistake all the time. Brent Calloway, our owner, has built the company around getting the jurisdictional details right from day one, so your project moves through plan check and inspection without stalls.
Our reviews from Los Serranos customers consistently mention two things: the permit work was handled without them getting stuck in the middle, and the material quality matched what was quoted. We spec brands like GAF, CertainTeed, and Owens Corning for roofing and fire-hardening work, and we coordinate the full scope from demo to final walk-through. One contractor, every system. That’s the Square One approach, and it’s what makes us a better fit for Los Serranos than a remodeler who only handles kitchens or a roofer who won’t touch structural work.
Styles & brands we work with
Construction Company in Los Serranos
When you hire us as your Construction Company in Los Serranos, you’re hiring a team that manages the ground-up work: demolition, structural framing, electrical and plumbing rough-in, roofing, siding, and final finishes. Los Serranos homes range from large-lot semi-rural properties near Los Serranos Country Club to older ranch-style houses along the Chino Hills border and newer tract infill. Each type comes with its own quirks. Older ranch homes often need panel upgrades and seismic tie-downs. Newer infill may need drainage corrections. We handle all of it under one contract.
Permit and Inspection Coordination
Because Los Serranos sits in San Bernardino County jurisdiction, every structural project needs a county building permit, not a Chino Hills city permit. Our team verifies jurisdiction before we file anything. We also handle county inspection scheduling, so you’re not calling for inspectors or wondering where your project stands.
Custom Additions and Ground-Up Work
For a Los Serranos room addition or a full custom build on a large lot, we manage site prep, grading, foundation work, framing, and every finish trade. Home additions in Los Serranos typically run $45,000 to $130,000. A full custom build goes higher, but the work is scoped line-by-line before we start so you know exactly what you’re paying for.
Remodeling Contractor in Los Serranos
As your Remodeling Contractor in Los Serranos, we take the same full-scope approach to interior renovations that we bring to new construction. A full kitchen remodel in Los Serranos runs $14,000 to $45,000 depending on cabinet grade, countertop material, and whether walls move. A bathroom remodel lands between $9,000 and $28,000. We install brand-sourced materials from KraftMaid, Wellborn, Cambria, Silestone, Kohler, and Moen, so you’re not limited to whatever a single trade happens to stock.
Kitchen and Bath System Coordination
Most remodels fail when the cabinet installer and the plumber aren’t talking to each other. We eliminate that. Your cabinet layout, plumbing fixture placement, countertop templating, and backsplash installation all get coordinated by one project lead. No finger-pointing, no “that’s not my trade” phone tag. Your remodel, fully managed.
Whole-Home and Multi-System Remodels
If you’re updating a 1970s ranch near the Chino Hills border and the project touches bedrooms, baths, the kitchen, and the exterior, we’re built for that. We handle structural changes, window replacement, siding, and even hardscaping under the same contract. That’s the single-source advantage most local remodelers can’t offer.
Trusted Brands We Service in Los Serranos
Square One Builders sources from 50+ nationally recognized material brands, including GAF, CertainTeed, Owens Corning, and IKO for roofing. We also work with James Hardie for siding, Cambria and Silestone for countertops, and Kohler and Moen for plumbing fixtures. For Los Serranos customers, that means you get real brand options at different price tiers without switching contractors. We spec the right material for your project, and we coordinate delivery and installation so materials arrive when the job needs them, not three weeks early or two weeks late.
Common General Contractor Problems We See in Los Serranos Homes
- Wrong jurisdiction permit. A job on one side of a street in Los Serranos can be county while the other side is Chino Hills city. Pulling the wrong permit stalls plan check for weeks, and most homeowners don’t discover the mistake until an inspector shows up.
- Skipped fire-hardening details. Hot inland summers and Santa Ana winds make Class A roofing and ember-resistant vents a real necessity here, not an upsell. Homes that skip these details can hit insurance eligibility problems after a wind event.
- Hillside drainage failures. Los Serranos has sloped lots near the country club and along the Chino Hills edge. When winter rains hit, poor grading shows up as slope erosion, foundation seepage, and failed county drainage inspections.
- Aging electrical panels on ranch homes. Original ranch-era panels often can’t carry the load of a modern kitchen or an addition. We check panel capacity early in the scope so you’re not surprised by an electrical upgrade mid-project.
See the difference
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AfterPricing for General Contractor in Los Serranos, CA
Los Serranos pricing tracks closely with Chino and Chino Hills because we’re in the same regional market, not a discount zone. Here’s what current projects are running across the 91709 ZIP:
| Project Type | Typical Los Serranos Range |
|---|---|
| Kitchen Remodel | $14,000 – $45,000 |
| Bathroom Remodel | $9,000 – $28,000 |
| Home Addition | $45,000 – $130,000 |
| ADU Construction | $90,000 – $220,000 |
| Roof Replacement | $8,000 – $20,000 |
What moves the number is scope, material grade, and site conditions. A kitchen with a load-bearing wall removal and custom cabinetry lands at the higher end. A cosmetic bath refresh lands lower. Call (877) 688-9930 for a free, line-item estimate from our team.
We Also Serve Cities Near Los Serranos
Square One Builders serves Los Serranos plus the surrounding communities of Chino, Yorba Linda, Montclair, and Pomona. If you’re right on the Chino Hills border and unsure which jurisdiction you fall under, call us and we’ll verify before you file anything. That’s part of why Los Serranos homeowners trust General Contractor in Los Serranos services from our team.
Serving Los Serranos, CA — Our Local Coverage Area
We’re based in the Los Serranos 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 General Contractor in Los Serranos
If your property is in the 91709 ZIP and sits on the unincorporated side of Los Serranos, you need a San Bernardino County building permit, not a City of Chino Hills permit. We verify jurisdiction using county parcel data before we file anything. Call (877) 688-9930 and we’ll check your address.
Los Serranos is in a high-fire-risk zone, and county inspectors enforce Class A roofing material with ember-resistant vent covers. We install GAF, CertainTeed, and Owens Corning Class A systems that meet county requirements, and we document the installation for your insurance records.
We start with a site grade and drainage assessment before any structural work begins, then coordinate drainage corrections with the foundation and grading plan. County inspectors in Los Serranos check drainage closely during winter rainy season. We build to pass the first time and document what was done.
A compliant Los Serranos quote includes county permit fees, fire-hardening materials like Class A roofing and ember-resistant vents, drainage and grading work, and electrical panel upgrades where needed. A cheap quote leaves those out and you pay for them later as change orders. Call (877) 688-9930 for a written, line-item quote.
Insurers increasingly ask for proof that fire-hardening and structural work was done to current county code, especially after a Santa Ana wind event. We hand you a documented compliance packet after every job, and that packet is what your insurer uses to verify your risk profile. It’s a small detail that saves real money later.
Call Square One Builders in Los Serranos
One contractor, every system. From the ground up, built to stay that way. If you’re planning a remodel, addition, or ADU in Los Serranos, call (877) 688-9930 to schedule your free estimate. We’ll walk the property, verify your jurisdiction, and give you a line-item quote that covers the full scope.
Written by Brent Calloway, Owner at Square One Builders, serving Los Serranos and surrounding communities.