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 San Antonio Heights
Most construction in San Antonio Heights isn’t a simple flat-lot job. It’s a hillside project with county permits, fire-clearance rules, and narrow private roads that limit how materials arrive. We plan for all of that before the first day of demolition. If you’re weighing a kitchen remodel, an ADU, or a full home addition in 91784, call us at (877) 688-9930 and we’ll walk you through what your specific property actually needs. No generic scope, no surprises after the contract is signed.
Why Square One Builders Is San Antonio Heights’s Preferred General Contractor Company
Homeowners around Euclid Avenue, Mountain Avenue, and the foothill roads above 23rd Street call us because we already know the county’s fire-safe construction details and fuel-modification rules. Our crews have worked steep lots where the driveway grade alone dictates crane scheduling and phased material staging. Brent Calloway, our owner, has built our reputation on one idea: scope it right from the ground up, and the build stays on schedule.
We’re not a specialty trade. We’re a General Contractor that handles the full project under one contract, from foundation and drainage to cabinetry and roofing. San Antonio Heights homeowners choose us because they don’t want to coordinate five separate crews on a hillside where every sub needs the same narrow access road. One contractor, every system.
Styles & brands we work with
General Contractor Services in San Antonio Heights
General Contractor Services in San Antonio Heights mean managing the entire build, not just framing and finish work. On hillside properties, that includes erosion control, retaining-wall coordination, and fire-rated construction details the county checks at multiple inspection points. A full home addition here typically runs $45,000 to $130,000. An ADU, which requires separate fire-safe approvals and often a fuel-modification zone review, lands between $90,000 and $220,000.
Hillside Additions and Structural Work
Most lots in San Antonio Heights slope enough that a simple room addition becomes a foundation-and-drainage project. We scope grading, retaining requirements, and utilities before we quote, so the price you see is the price that holds through inspection.
Coordinated Remodeling
A kitchen or bathroom remodel here still triggers county review when you move walls, reroute plumbing, or change venting. We run that from the first drawing to final sign-off, including material spec that meets hillside fire exposure. Your remodel, fully managed.
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.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Construction Company in San Antonio Heights
As a Construction Company in San Antonio Heights, Square One Builders handles scopes most remodelers won’t touch: detached garages with living space above, retaining walls on sloped lots, and site work that includes vegetation clearance and drainage basins. A garage conversion in this area usually runs $30,000 to $80,000, depending on whether the existing slab can support living-space loads.
Detached Structures and ADUs
Building a detached ADU on an acre lot means septic setbacks, well clearance, and county fire standards all come into play before the first inspection. We map out those distances early and design accordingly, so you’re not redesigning after the foundation is poured.
Grading and Drainage
Winter rains and debris flow from burned slopes change how any flat lot math works. We build erosion-control measures into every hillside scope, not as a change order later. The county expects it, and so should you.
Trusted Brands We Service in San Antonio Heights
We spec the right material for your project, not whatever is easiest to source. For roofing on fire-exposed hillside lots, we work with GAF, CertainTeed, and Owens Corning because their Class A fire-rated shingle systems hold up under Santa Ana wind conditions and pass county inspection without argument. For siding and exterior envelopes, James Hardie fiber cement is our standard recommendation on slopes where ember exposure is a real concern. We stock common components locally and can have special-order parts staged in phases when your drive limits how much material can sit on site at one time.
See the difference
Before
After
Before
After
Before
AfterCommon General Contractor Problems We See in San Antonio Heights Homes
- Fuel-modification clearance caught late. Skipping the county’s brush-clearance review until after foundation work begins forces expensive redesigns for roof overhangs and ember-resistant vent placement. We file that from day one.
- Narrow private roads breaking the schedule. Underestimating material haul distance and staging limits on drives like those off Euclid and Mountain Avenue leads to missed inspection sign-off windows. We plan crane dates and delivery phases before demo starts.
- Grading treated as a flat-lot exercise. Burned-slope runoff and debris-flow risk mean erosion control has to be engineered, not added as an afterthought. We design drainage into the foundation scope.
- Older utility lines on mid-century ranch lots. Many homes in 91784 run on electrical and plumbing that pre-dates current code. We factor upgrade costs into your quote rather than surprising you at rough-in.
Pricing for General Contractor in San Antonio Heights, CA
Pricing in San Antonio Heights reflects the hillside reality. Flat-lot pricing from Upland doesn’t transfer here because county fire clearances, slope engineering, and material staging change the labor and timeline. Here are the ranges we quote most often:
| Project | Typical Range in San Antonio Heights |
|---|---|
| Home Addition | $45,000 – $130,000 |
| ADU Construction | $90,000 – $220,000 |
| Garage Conversion | $30,000 – $80,000 |
These are full-scope numbers, not shell costs. They include county permit time, fire-safe detailing, drainage, and material delivery staged for your specific driveway. Call (877) 688-9930 to schedule your free estimate and get a written line-item quote based on your lot, not a flat-lot template.
We Also Serve Cities Near San Antonio Heights
While this page focuses on General Contractor in San Antonio Heights, our crews regularly work the foothill corridor through Upland, Claremont, Rancho Cucamonga, and Montclair. Each area has its own permitting body and fire-zone rules, and we adjust scope accordingly.
Serving San Antonio Heights, CA — Our Local Coverage Area
We’re based in the San Antonio Heights 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 San Antonio Heights
Yes. Because San Antonio Heights is unincorporated, every construction permit goes through San Bernardino County, not Upland or a local city. On top of standard building permits, the county requires fire-safe construction details and a fuel-modification clearance zone for detached ADUs. We handle both tracks from the first site visit, so your ADU isn’t held up at framing by a brush-clearance inspection. Call (877) 688-9930 for a site-specific fee breakdown.
We engineer it before we quote it. A sloping acre lot in San Antonio Heights needs erosion-control measures, debris-flow consideration, and often a retaining wall, none of which are optional additions here. We include those items in your original scope so the price doesn’t move once grading begins.
It can delay the entire project if it isn’t planned for. Narrow private roads off Euclid Avenue and the foothill drives force us to stage materials in phases and sometimes schedule a crane for truss delivery. We map that out before demolition so rough-in and inspections don’t slip.
You should expect to pay for what the slope demands. A bathroom remodel in San Antonio Heights runs roughly $9,000 to $28,000, while a kitchen remodel spans $14,000 to $45,000. The hillside adds cost when venting, water lines, or structural supports must be rerouted around grade changes. We quote those items line by line, so you know exactly what you’re paying for. Call (877) 688-9930 for your exact number.
Upland runs its own building department with its own timeline. San Antonio Heights goes through San Bernardino County, which adds fire-safe construction review and fuel-modification clearance on top of standard structural inspections. That means more documentation up front and a longer pre-construction phase, but we handle every submittal and inspection for you.
Building in San Antonio Heights takes a contractor who already knows how the county, the fire clearance, and the slope interact. Square One Builders handles all of it under one contract, one schedule, and one accountable team. Brent Calloway started this company to give foothill homeowners exactly that. Call (877) 688-9930 to schedule your free estimate, or stop by and show us your lot. We’ll tell you straight what it will take.
Written by Brent Calloway, Owner at Square One Builders, serving San Antonio Heights and the surrounding foothill communities.