Sunrooms & Patio Rooms in Westminster, CA
Premium Sunroom Construction installs custom sunrooms and patio rooms throughout Westminster — from the heart of Little Saigon to the quiet streets off Westminster Boulevard. When the lot is modest and the guest list isn't, an enclosed patio is how a Westminster backyard learns to live large.
Outdoor Living Spaces
YOUR LOCAL SUNROOM CONTRACTOR
Trusted Sunroom & Patio Room Contractor Serving Westminster Homes
Westminster's 1960s neighborhoods were platted with modest, efficient lots — which was fine until the household grew and the holidays started landing at your house. When twenty people show up for a celebration, the dining room surrenders fast. A patio room turns the slab behind the house into the gathering room that handles it: weatherproof, bug-free, and connected to both the kitchen and the yard.
We make the project painless. A design consultant comes to your Westminster home for a free in-home quote, we check the slab and footings, our office runs the engineering and City of Westminster permits, and factory-trained crews handle the install. The Buena Park showroom is fifteen minutes up the 39 if you want to stand inside the rooms before deciding — and with C-Thru building in Riverside, the materials are California-made and quick to arrive.
- Licensed, bonded & insured California contractor
- Compact-lot design experience — rooms that fit without crowding the yard
- Authorized dealer: Four Seasons, C-Thru & Duralum product lines
- All three product lines are manufactured right here in California
- Free in-home design consultations — 7 days a week
WHAT WE BUILD
Custom Sunrooms & Patio Enclosures in Westminster
Gathering rooms, quiet tea rooms, home offices — and patio covers when shade is all the yard needs. Sized to your lot, priced at your kitchen table.
Four-Season Sunrooms
Insulated glass rooms with CONSERVAGLASS NXT glazing — bright, cool, and usable every day of the year, even on a compact footprint.
Three-Season Patio Rooms
The Westminster favorite: enclose the existing covered patio into a real gathering room without sacrificing what's left of the yard.
Solid-Roof Patio Enclosures
Insulated EPS roof panels with C-Thru Alpha and Omega wall systems — a quiet, finished room that reads as part of the original house.
Screen Rooms
DuraScreen enclosures for mild coastal-adjacent evenings — open-air dining without bugs landing in the phở.
Aluminum Patio Covers
Duralum Weatherwood solid and lattice covers in 8 woodgrain colors — engineered to 130 MPH wind and Seismic D, never needs painting.
Conversions & Upgrades
Enclose the patio cover you already have into a full room, or modernize an aging enclosure with new glass, doors, and screens.
WHY HOMEOWNERS HIRE US IN WESTMINSTER
We Know Westminster Homes
Modest lots, busy households, and backyards that have to earn their keep. Here's how we deliver.
Rooms That Fit the Lot
On a 6,000-square-foot lot, every yard-foot matters. We design rooms that use the slab you already have and keep the rest of the yard open — no variance, no crowding the fence line.
Built for Big Gatherings
Tết at your house? Graduation party for forty? A patio room adds the overflow space that keeps the party together — connected to the kitchen, sheltered from the drizzle, and cleaned up in minutes.
Westminster Permit Experience
Plan submittals, building permits, and inspections with the City of Westminster — handled in-house from first drawing to final sign-off.
California-Made Product Lines
C-Thru builds in Riverside, Duralum in Sacramento, Four Seasons manufactures in California — and our Buena Park showroom is fifteen minutes away. See the rooms full-size before you sign.
OUR PROCESS
From Free Quote to Finished Room
Five steps, one point of contact, and a firm price before anything is ordered.
Free In-Home Consultation
A design consultant visits your Westminster home, measures the patio and lot, and prices options that genuinely fit — no pressure, no obligation.
Design & Product Selection
Choose your line — Four Seasons, C-Thru, or Duralum — plus glass, frames, and doors. The quote is firm and itemized.
Site Check, Engineering & Permits
We verify your slab and footings, then run engineering and City of Westminster permitting in-house.
Professional Installation
Factory-trained crews assemble your pre-engineered room in days to a few weeks on site — most projects complete within a few months of signing.
Final Inspection & Warranty
City final inspection, a complete walkthrough, and your transferable lifetime manufacturer warranty registered in your name.
WESTMINSTER SUNROOM FAQs
Common Questions From Westminster Homeowners
Enclosing an existing covered patio as a three-season room starts around $15,000-$25,000; a fully insulated four-season sunroom with premium glass runs $30,000-$70,000+. Because most Westminster projects build on the existing slab, site costs stay modest — and the total typically lands 50-70% under a comparable room addition. Exact numbers come from your free in-home quote.
Done right, the opposite. A glass-walled room doesn't visually wall off the yard the way a stucco addition does — you see straight through to the fence line, so both the room and the yard feel bigger. We design to your lot's setbacks so the remaining yard stays genuinely usable.
Yes — the City of Westminster requires building permits for sunrooms, patio rooms, and most patio covers. Our office prepares the engineering and plans, files everything, and meets the inspectors. You don't handle any of it.
A few months from contract to final inspection, with permitting taking the largest share. On-site assembly runs days to a few weeks — pre-engineered systems go up fast, and C-Thru's Riverside factory keeps material lead times short.
That's what most Westminster clients build it for. We plan wide openings to the kitchen and yard, durable flooring, ceiling fans or a mini-split for comfort, and lighting that works for a dinner that runs past midnight. It's the room that absorbs the party.
A patio room (or patio enclosure) is usually built on your existing patio slab for three-season use. A four-season sunroom is fully insulated and can tie into your home's heating and cooling for year-round comfort. We build both and we'll recommend the right fit at your free quote.
Three California-built lines: C-Thru Sunrooms (manufactured in Riverside), Four Seasons Sunrooms with CONSERVAGLASS NXT glazing, and Duralum (Sacramento). Every line carries a transferable lifetime warranty that stays with the home.
Yes — financing options are available, and your design consultant can lay out payment scenarios alongside the project price at your free in-home quote.
SERVING SOUTHERN CALIFORNIA
Sunroom & Patio Room Builder Throughout Orange County
Beyond Westminster, Premium Sunroom Construction installs sunrooms, patio rooms, and patio covers across Orange, Riverside, San Diego, and Los Angeles counties.
OUR QUOTE PROCESS
Schedule
Fill out a quick form or call to schedule your no-obligation quote.
Measure
One of our certified estimators will visit to measure for your project.
Quote
You'll have all the info and pricing to make an educated decision.
or call 951-634-7776
WHAT OUR CLIENTS SAY
Hear From Our Happy Customers
Real Stories, Real Transformations
Build Your Westminster Sunroom or Patio Room
Compact-lot smarts, gathering-ready design, permits handled for you, and free in-home quotes seven days a week. Let's make your backyard the biggest room in the house.