Window Replacementin Westminster, CA
Window replacement in Westminster raises a federal rule and a local gap. Lead-safe work practices always apply when windows are replaced in housing built before 1978, which covers most of the city's stock. The City's permit exemption list never mentions windows, so ask the Building Division whether even a same-size swap needs a permit before ordering.
In the 1970s a refugee influx made the stretch of Bolsa Avenue between Magnolia Street and Brookhurst Street the city's best known district, according to Wikipedia, and the same decades built much of the housing around it. The Census Bureau's 2024 estimates count 8,578 homes from the 1960s and 7,104 from the 1970s among 28,953 units, with wide margins of error. Any window still original to those houses is now 45 to 65 years old, and we found no Westminster survey of how many are.
This page covers the permit question, the lead rule, glass and heat, who decides on windows in different housing types, new openings and egress, fire review, and how an install runs. The municipal code text we cite comes from GoCodebook, a third-party mirror, because the City's website and the usual code hosts refused our tools, so confirm points with the Building Division. Price figures are on our windows page.
Westminster Building Division and Planning rules that apply to window work
Where windows permits come from in Westminster: City of Westminster Community Development Department, Building Division.
- The City's exemption list has no item for replacement windows or doors; the nearest items are window awnings on R-3 and U buildings projecting no more than 54 inches from the wall, and finish work. Ask the Building Division whether a same-size window swap needs a permit, because the code text read here does not exempt it.
- The 2025 California Energy Code applies in Westminster without local amendments (Ordinance 2626), so replacement windows are governed by the state energy rules.
- A cantilevered bay window may project 18 inches into a required setback, and attached chimneys 20 inches, but neither may come closer than 3 feet to a side property line; enlarging or adding windows near a lot line is therefore a setback question as well as a building code one.
- Under EPA's Renovation, Repair and Painting rule, window replacement in housing built before 1978 is always covered, which means a certified firm and lead-safe practices are needed regardless of how much paint is disturbed.
Does window replacement need a permit in Westminster? The City's exemption list does not say
The City's Administrative Code lists the work that needs no building permit: sheds up to 120 square feet, masonry walls or fences up to 4 feet, retaining walls up to 4 feet, painting and cabinet finish work, some pools, decks, awnings, sidewalks and driveways. Replacement windows and doors are not on it. The nearest items are window awnings on R-3 and U buildings that project no more than 54 inches, and finish work.
That is an absence, not an answer. We found no City statement about a same-size swap, so the question for the Building Division is concrete: does a like-for-like change-out need a permit, and does a changed opening need plans? Ask by email so the reply is in writing. The code also says exempt work must still meet the technical codes.
Westminster's zoning code ties a Zoning Clearance to its review of any building permit, so a window job that does need a permit also gets checked against the zone. A like-for-like swap raises nothing there, while a larger opening near a lot line can, as the section on new openings below explains.
Lead-safe window replacement in a Westminster house built before 1978
Under EPA's Renovation, Repair and Painting rule, paid window replacement in a house built before 1978 always needs a certified firm using lead-safe practices, no matter how little paint is disturbed. Minor repair work is exempt only at 6 square feet or less of paint per room indoors or 20 square feet or less outdoors, and window replacement and demolition are carved out of that exemption.
The 2024 Census table puts 21,581 of 28,953 units, 74.5 percent, in the pre-1980 columns, and it cannot separate 1978 from 1979. The rule therefore reaches most jobs on 1960s and 1970s tract homes, but we cannot prove it reaches every house. If yours was built in 1978 or later, say so and ask for the permit record, and do not assume.
South Coast AQMD asbestos rules can also apply to remodels and demolition, which is worth a question if old putty, caulk or stucco is cut out around a frame.
- Is the firm EPA-certified for lead-safe renovation, and can you see the certificate?
- How are the old sashes removed, bagged and taken away?
- What is the plan for dust in the rooms where the windows come out?
Glass labels, heat and the 2025 Energy Code: what governs replacement windows in Westminster
The 2025 California Energy Code applies in Westminster without local amendments (Ordinance 2626), so replacement windows follow the state rules as written. We did not read the adopted section on replacement windows, and city handouts elsewhere disagree on U-factor and solar heat gain numbers, so we print none. Ask for dual glazing carrying the National Fenestration Rating Council label and meeting Title 24, Part 6 for your climate zone, and ask the seller to name the zone.
Heat varies across the county. The NOAA Santa Ana Fire Station averages 30.0 days a year at or above 90 F and 2.2 days at or above 100 F, while John Wayne Airport, about 8.9 miles southeast, averages 12.8 days and an August high of 80.4 F. Neither station is in Westminster and we do not know which one the city resembles, so a west-facing living room and a shaded bedroom are separate glass questions for the seller.
Many web pages and old articles still advertise the federal window tax credit. The IRS says the 25C Energy Efficient Home Improvement Credit is not allowed for property placed in service after December 31, 2025, according to its 2025 law FAQ. We did not verify any state or utility rebate.
Replacement windows for a 1960s tract house, a mobile home or an apartment: who decides
Single-family detached homes are 53.6 percent of Westminster's units, single-family attached homes 7.6 percent, buildings of two to four units 10.3 percent, buildings of five or more 18.3 percent and mobile homes 10.2 percent. The person who decides on windows changes with the type: the owner of a detached house, the association or owner of a multiunit building, and the park and the owner of a mobile home.
In a condominium the frames, the glass and the exterior wall may be common property, so get the board's written approval and ask for its list of approved styles. We read nothing about HOA coverage in Westminster, and we did not research mobile home park rules or the state rules for mobile homes, so ask before ordering.
For a detached house, the code text we read sets no style rule for a like-for-like swap. New construction is another matter: an addition must be compatible with the existing materials, color palette and architectural theme, and an ADU must match the main house, so windows become part of that review. See the Westminster room addition page and the Westminster ADU page.
Changing a window opening, adding egress or replacing a sliding door in Westminster
A bigger or new opening is a different job from a swap. It cuts framing, may need a new header and disturbs the exterior finish, and it can raise a setback question. A cantilevered bay window may project 18 inches into a required setback, and attached chimneys 20 inches, but neither may come closer than 3 feet to a side property line. Enlarging or adding windows near a lot line is therefore a zoning matter as well as a building code one.
Bedroom egress and safety glass in hazardous locations have size and sill rules in the California building and residential codes. We did not read those sections, so we print no dimensions, and your designer should cite the section on the permit drawing. A sliding glass door is the same kind of question as a window: a same-size swap is the open permit question above, and a wider opening is a framing job.
A window in a garage wall is not a problem in the code text we read, which says a garage may have windows and drywall but must stay available for parking and may not be habitable space. A garage turned into living space belongs on a legal unit, and our Westminster ADU page covers that route.
Windows and fire: OCFA, an unconfirmed hazard zone and what to ask about glass
Fire review in Westminster comes from the Orange County Fire Authority, which the City's code names as the authority having jurisdiction and which lists Westminster among its member cities. The CAL FIRE zone data we could read, a 2011 layer, showed no zone polygons around the city, and a May 2025 report on Orange County cities added to the 2025 maps did not name Westminster. We did not read the 2025 maps, so we do not say your parcel sits outside a zone.
Westminster adopted the 2025 Wildland-Urban Interface Code without local amendment, and its local roof rule is written for areas outside zones and wildland-urban interface areas. A parcel inside a mapped zone follows state-set rules that can reach glazing, so check the parcel on CAL FIRE's viewer, then ask the Building Division what applies to a replacement window.
The San Diego Freeway and a short stretch of the Garden Grove Freeway cross the city. We found no Westminster rule on sound ratings for windows, so if traffic noise is the reason you are replacing glass, ask each seller for the sound transmission class of the unit and compare the numbers in writing.
Lead times, install day and paperwork for window replacement in Westminster
A whole-house job runs about 1 to 2 weeks of measuring and quoting, then 4 to 8 weeks while the factory builds each unit to size, then 1 to 3 days of installation for a typical house of 10 to 15 windows, done one opening at a time so the house stays closed. Stucco and trim repair adds 1 to 3 days. Custom sizes and special glass take longer, so ask for the manufacturer's date in writing.
A retrofit unit fits inside the existing frame and keeps the stucco and trim, while a full-frame replacement removes the frame and usually means patching and painting around it. Ask which one your quote assumes, because the price and the repair work differ.
MDG Builders, CSLB #1040337, handles the order, the schedule and any permit step as general contractor, and a licensed installer sets the units. CSLB's C-17 Glazing classification covers glass work in any structure, and its text does not name windows, so we claim no class and you can ask the installer for its license. Under Section 303.8 of the City's Administrative Code a permit ends if the contractor changes mid-job. State law limits a down payment to the lesser of $1,000 or 10 percent of the contract price.
Window photos from Westminster and nearby homes
Window scenes tied to Westminster and the Orange County communities around it, from flashing and glass details to finished openings. Tap a photo to enlarge it.
What windows costs around Westminster
On our windows page, vinyl replacement windows are priced at about $550 to $1,200 each installed, a whole house of 10 to 15 windows lands near $14,000 to $28,000, and wood and fiberglass cost more. The ranges sit among three Los Angeles sources: Remodeling magazine's 2025 Cost vs. Value report, which prices vinyl replacement at $23,783 with about 83.2 percent recouped and wood at $27,913 with 81.9 percent; Angi's July 2026 Los Angeles average of $19,356, with a typical range of $16,359 to $22,377; and a ConsumerAffairs page that states no cost method. None is a Westminster quote, the City's fee schedule was not readable, and any permit fee shows as a separate line in a written proposal. The license check guide shows how to verify a firm, and the subcontractor guide explains how a general contractor hands off the install. Nearby cities set their own rules, so compare window replacement in Garden Grove, Huntington Beach, Santa Ana and Los Angeles. A bathroom window belongs on the Westminster bathroom page, and the Westminster area page lists every trade we cover in the city.
| What it covers | Typical range |
|---|---|
| Vinyl window, installed, each | $550 to $1,150 |
| Wood or fiberglass window, installed, each | $950 to $2,400 |
| Whole house, 10 to 15 windows | $14,000 to $28,000 |
| Glass options, per window | Double-pane $500 to $2,000. low-E $300 to $1,100. tempered $200 to $700. |
| Remodeling Cost vs. Value 2025, Los Angeles | Vinyl $23,783. wood $27,913. |
| New or enlarged egress opening | $3,200 to $6,500 |
Other work we manage in Westminster
Westminster window replacement questions, answered
Do I need a permit to replace windows in Westminster?
Ask first, because the City's text does not answer it. Westminster's list of work exempt from a building permit names awnings, finish work and small structures but not replacement windows or doors, and we found no City statement on a same-size swap. A larger opening is a framing change and should be treated as permit work. Ask the Building Division by email.
Do replacement windows need to be lead-safe in Westminster?
Yes if the house was built before 1978. EPA's rule always covers window replacement in housing from before that year, so a certified firm and lead-safe practices apply however little paint is disturbed. About 74.5 percent of Westminster units were built before 1980 and the data cannot separate 1978 from 1979, so assume the rule applies unless the build year says otherwise.
How much do replacement windows usually cost?
Plan on roughly $550 to $1,200 per vinyl window installed, which puts a whole house of 10 to 15 windows near $14,000 to $28,000, and wood or fiberglass costs more. The figures come from Los Angeles sources, not a Westminster quote, and fire-rated glass, custom sizes and stucco repair push them higher.
How long does it take for new windows to be installed?
Installation takes 1 to 3 days for a typical house of 10 to 15 windows, but the order takes longer: 4 to 8 weeks for the factory to build the units, plus 1 to 2 weeks of measuring and quoting beforehand. Custom sizes and special glass add time, and the manufacturer quotes the date.
Are double pane windows required in California?
Typically yes for replacement windows, with a gap in what we read. The 2025 California Energy Code applies in Westminster without local amendments, and NFRC-labeled dual glazing is the usual compliance path, but we did not read the adopted section and print no U-factor numbers. Ask the seller for the NFRC label and the climate zone it assumes.
Which is better, replacement windows or new construction windows?
It depends on the frame. Replacement (retrofit) windows fit inside the existing frame and keep the stucco and trim, while new construction or full-frame windows replace the frame and usually mean patching and painting around them. Choose full frame when the frame is rotted or the opening changes, and ask the quote to say which it assumes.
Is replacing home windows worth it?
Partly. Remodeling magazine's 2025 Cost vs. Value report for Los Angeles shows about 83.2 percent of a vinyl replacement job recouped at resale and 81.9 percent for wood. We print no energy savings figure because we found no Westminster source, and the federal 25C tax credit does not apply to windows placed in service after 2025.
What size egress window is required in a bedroom?
The California codes set a minimum size and sill height for bedroom egress, but we did not read those sections, so we print no dimensions. A new or enlarged egress opening is also a framing change, and near a lot line it falls under the City's setback rules. Have your designer cite the section on the permit drawing and ask the Building Division.
Tell us about your Westminster windows
Tell us the street or neighborhood, roughly when the house was built, how many windows and doors you want replaced and whether the frames are original, and we will plan the visit around the lead rule and the permit question.