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 Westminster
Most Westminster homeowners don’t need a contractor until they open a wall and find something nobody planned for. That’s the moment the right general contractor matters. San Mateo Construction works across all three Westminster ZIP codes, 92683, 92684, and 92685, and we’ve been inside enough 1950s and 1960s ranchers in this city to know exactly what’s behind the stucco before we touch it. Our General Contractor team manages the full scope, roofing to foundation, and we’re one phone call away at (855) 901-7266. We quote honestly, write allowances into the contract for the things Westminster homes hide, and we never surprise a homeowner with a change order they didn’t approve in writing first.
Why San Mateo Construction Is Westminster’s Preferred General Contractor Company
Westminster isn’t a generic Orange County suburb. It’s a city shaped by Little Saigon, by multi-generational families who expand rather than move, and by permit histories that don’t always match what’s inside the walls. That matters when you’re hiring a contractor. We’ve worked up and down Bolsa Avenue, through the residential streets around Sigler Park, and into the neighborhoods east of Beach Boulevard. Our crews know how Westminster’s postwar tract homes were built and how they’ve been modified over the last fifty years.
Noel Carrington, who leads San Mateo Construction, built our approach around one principle: a contractor should write the real scope, not the optimistic one. That’s why we schedule a pre-inspection before demo on older Westminster homes. We look at the breaker panel, the galvanized piping, the framing in the attic, the stucco for dry-rot. Then we write a bid that already accounts for what we expect to find. Our Westminster clients consistently tell us the same thing: the number we gave them before demo matched the number at the end, because we did the legwork on the front side.
We also carry the brand access that most single-trade remodelers can’t offer. Need a kitchen with Cambria or Caesarstone countertops and KraftMaid cabinetry? A roof under GAF or Owens Corning? Windows from PGT? You get one contract and one accountable team, not four subcontractors pointing fingers at each other.
Styles & brands we work with
Hire a General Contractor in Westminster
Hire a General Contractor in Westminster when the project touches more than one trade. If you’re remodeling a kitchen, you’re dealing with plumbing, electrical, cabinetry, countertops, and probably flooring. A dedicated contractor coordinates all of it, pulls the permit, schedules inspections, and stays accountable for the finished work. In Westminster, where many homes are 60 to 70 years old, that coordination matters more than it does in newer cities. A kitchen remodel here typically runs $14,000 to $45,000, depending on whether we’re opening walls, moving plumbing, or replacing the electrical rough-in.
Full-Scope Remodels
We run whole-home remodels in Westminster where the kitchen, bathrooms, flooring, and lighting all get addressed under one plan. This is the most efficient way to handle a 1960s ranch that’s been piecemeal-updated for decades. One contract, one schedule, one accountable party.
Permit-Ready Planning
Before we write a bid, we check what the City of Westminster will require once walls are open. That means looking at the existing electrical, plumbing, and any prior unpermitted work. The goal is a permit set that passes the first time, not a surprise stop-work order mid-project.
General Contractor Services in Westminster
General Contractor Services in Westminster cover the full exterior-to-interior scope, from a re-roof to a rear addition. Many homeowners come to us because they want to add square footage instead of moving. Westminster’s ranch homes were built small, and multi-generational families have been expanding them for decades. A home addition here typically runs $45,000 to $130,000. An ADU construction project, including site work, utility work, and modern prefab options, runs $90,000 to $220,000.
Garage Conversions and ADUs
Westminster has one of the highest concentrations of garage conversions in Orange County, and many were built without permits years ago. We handle both legalizing older conversions and building new ADUs through vetted manufacturers like Abodu and Dvele. A legal garage conversion with the required electrical, insulation, and egress typically runs $30,000 to $80,000 here.
Exterior Systems and Envelope
A remodel isn’t just interior finishes. We replace windows, re-roof, install James Hardie siding, and rebuild damaged framing. If the exterior envelope is compromised, no amount of new cabinetry will fix a leaking wall. We address the shell and the finishes under one contract.
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.
Trusted Brands We Service in Westminster
We don’t push a single brand on Westminster clients. We help you choose from a curated set, based on your budget and the specific conditions of your home. For roofing, that includes GAF and Owens Corning. For windows and doors, PGT and Therma-Tru. For cabinetry, KraftMaid and Wellborn. For countertops, Cambria, Silestone, and Caesarstone. We keep supplier relationships across every major system so you’re getting name-brand materials that are actually available, not whatever the local yard happened to have in stock last week. When a Westminster homeowner near the 92683 ZIP needs a specific window line or a roof under Tamko or Boral, we can order it without a three-week sourcing delay.
See the difference
Before
After
Before
After
Before
AfterCommon General Contractor Problems We See in Westminster Homes
- Unpermitted rear additions and garage conversions: A huge share of Westminster’s ranch homes were expanded by multi-generational families over the decades, frequently without permits. Once we open a wall, legacy wiring and undersized framing in those additions has to be brought to code before the inspector will sign off on new scope.
- Knob-and-tube wiring and galvanized plumbing: Homes built between the 1950s and early 1970s often still have original electrical or supply piping. A remodel that opens walls triggers code requirements to replace what’s exposed, which is a real cost and a real safety improvement.
- Dry-rot and termite damage in stucco and wood framing: Westminster’s coastal-inland climate, mild wet winters and warm dry summers, is easy on foundations but hard on old wood. We regularly find termite-damaged subfloor and dry-rotted window framing once demo starts.
- Failed waterproofing in older bathrooms: Lead pan shower construction and tile-over-drywall were common in postwar bathrooms. We see failed waterproofing constantly, which is why we use Schluter systems on every wet-area install.
Pricing for General Contractor in Westminster, CA
Westminster pricing reflects what’s actually inside the walls. A kitchen remodel runs $14,000 to $45,000. A bathroom remodel runs $9,000 to $28,000. A home addition runs $45,000 to $130,000. A legal garage conversion runs $30,000 to $80,000, and an ADU runs $90,000 to $220,000. Those ranges account for what we know Westminster homes hide: legacy wiring, galvanized pipe, unpermitted framing, dry-rot. The low end assumes minimal surprises. The high end assumes full rough-in replacement and structural repair. We write allowances into every contract so the number doesn’t move without your written approval. Call (855) 901-7266 to schedule your free estimate, and we’ll put the real number in writing before you commit to anything.
| Project | Westminster Price 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 |
| Garage Conversion | $30,000 – $80,000 |
Because Westminster’s 1950s and 1960s ranch homes were often expanded by multi-generational Vietnamese families without permits, opening walls frequently reveals unpermitted garage conversions or rear additions whose legacy wiring and framing must be brought up to current code before any new scope can be signed off. We’ve built our entire quoting process around this reality. We inspect first, write allowances into the contract, and price any surprise in writing before we touch it. On a Bolsa Avenue pho restaurant build-out, our crew opened the wall for a new Type I hood and found the original 1960s knob-and-tube wiring feeding the kitchen line. We added a change order for a full rough-in electrical upgrade and had the city inspector sign off before the hood was set. In a nearby ranch home off Bolsa, a bathroom remodel exposed failed lead pan waterproofing and termite-damaged subfloor, which we priced in writing and corrected before tile went down. That’s how we operate everywhere in Westminster, from the commercial corridor to the residential streets.
We Also Serve Cities Near Westminster
San Mateo Construction covers Westminster and the surrounding Orange County cities. Our General Contractor in Westminster team also serves Midway City, Garden Grove, Stanton, and Huntington Beach. If you’re a few minutes outside the city line, the same crews, same brand access, and same honest quoting process apply. Call (855) 901-7266 and tell us where the project is.
Serving Westminster, CA — Our Local Coverage Area
We’re based in the Westminster 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 Westminster
Because Westminster’s postwar housing stock routinely contains legacy wiring, galvanized plumbing, unpermitted framing, and dry-rot that no visual estimate can catch. A responsible contractor writes allowances into the contract for exactly these conditions, so the final number reflects what was actually behind the stucco, not what a low bid hoped was there. We inspect before bidding and price changes in writing. Call (855) 901-7266 for an estimate that accounts for Westminster’s real housing stock.
Yes. Westminster requires permits for garage conversions used as living space, and the city enforces parking and zoning requirements for multi-generational housing. A conversion that skips this becomes a liability when you sell or refinance, and inspectors can flag it during any future permitted work. We handle the permit set and inspections. Call (855) 901-7266 to discuss your specific property.
We stop work, document what’s there, and bring the affected scope up to current code through a permit revision. The homeowner sees a written change order with the exact cost before we proceed. This is the only legal path, and it’s the path that protects the value of your Westminster home. Call (855) 901-7266 to talk through what we’re likely to find on your block.
The big four are knob-and-tube wiring, galvanized steel plumbing, termite-damaged or dry-rotted wood framing, and failed waterproofing in older bathroom dry-pack construction. Homes off Beach Boulevard and around Sigler Park show these issues consistently. We price them as allowances rather than surprises. Call (855) 901-7266 for a pre-inspection walkthrough.
Yes. Many of our Westminster commercial projects run through Bolsa Avenue’s Little Saigon corridor, where permits, inspections, and client communication routinely happen in Vietnamese and English. We coordinate with bilingual subcontractors and work with city inspectors on the schedule that makes sense for a restaurant or retail build-out. Call (855) 901-7266 to discuss your commercial scope.
Written by Noel Carrington, Owner at San Mateo Construction, serving Westminster and Orange County’s postwar housing stock with honest, written-in-advance pricing.