Free in-home measure and quote - PGT, CGI and CWS impact lines compared on your actual openings, style by style
Window Company in Foster City, CA
Window and door work in Foster City runs into two problems most Peninsula contractors rarely see: salt air off the lagoon grid and a housing stock that’s aging all at once. Most homes here were built between the mid-1960s and mid-1980s, and the original single-pane aluminum sliders are now at the end of their service life all over town. We’re Westlight Windows & Doors, an independently owned and operated Kingswell location, and we work Foster City every week. Call (903) 354-7134 and a live person answers, day or night.
Why Foster City Homes Are Different
Foster City is built on engineered bay-fill, not native soil, and the ground settles unevenly over decades. Practically every contractor who’s worked here long enough has seen the result: door and window frames that rack out of square by an eighth of an inch or more, binding at the latch, gaps at the corners, sashes that won’t track. You don’t see this pattern in San Mateo or Belmont. The fix is a full-frame replacement that gets shimmed and squared on site, not an insert job that inherits the old frame’s problems.
The lagoon network adds a second layer. Homes within a few hundred yards of the water eat aluminum frames and door hardware fast. Persistent salt-laden marine air, combined with strong afternoon bay winds, drives premature corrosion of aluminum sliders and weatherstripping breakdown. We regularly see lagoon-facing units needing full window replacement within 15 to 20 years of the last install, roughly half the lifespan the same product achieves a mile inland. That’s not a product defect. That’s Foster City.
Most of the housing stock is two-story condos, townhomes, and tract single-family homes, many governed by HOAs with their own architectural review processes. The practical consequence: product choices often have to match what the association will approve, and noise rules can limit work hours. We’re used to both and can talk through the specifics before you commit.
Our Main Foster City Services
Foster City homeowners call us most often for two things: replacing windows that have fogged, corroded, or stopped opening, and installing new doors that seal properly against bay wind. Here’s what each job actually involves here.
Window Replacement in Foster City
Replacing windows in Foster City usually means pulling the entire old frame, not just swapping glass. The original aluminum sliders from the 1960s through 1980s were built for a different climate, and most have warped or corroded at the corners. We assess each opening for racking caused by bay-fill settlement before ordering anything, so the new window sits square. Learn more about Window Replacement in Foster City including pricing and what a typical lagoon-facing condo job looks like.

Window Installation in Foster City
Some Foster City homeowners already have their windows picked out, or they’re replacing broken glass after storm damage, and need a careful install that actually seals. The salt air here is unforgiving on flashing and sealant, so we use materials rated for coastal exposure and check the existing opening before the new window goes in. See Window Installation in Foster City for how we approach installations in condos, townhomes, and single-family homes across the city.

Door Installation in Foster City
Doors in Foster City take a beating from afternoon bay wind and salt mist, and a door that’s out of square because the ground settled will never latch right until the frame is corrected. We install entry doors, patio sliders, and French doors with thresholds and weatherstripping chosen for marine air, and we square the rough opening before the door goes in. Door Installation in Foster City covers the common door jobs we handle and what they cost here.

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.
Brands We Service in Foster City
We install product from eight manufacturer lines, including impact-rated PGT and CGI for wind-driven rain, energy-efficient ECO Window Systems for Foster City’s fog and salt exposure, and Therma-Tru entry doors built for coastal air. Parts are stocked locally in the Bay Area, so most service visits happen within a short window. See our brands for the full list.
Pricing for Window Company in Foster City, CA
| Service | Typical range in Foster City |
|---|---|
| Full-frame window replacement (per window) | $800 - $1,500 installed |
| Insert window replacement (per window) | $500 - $900 installed |
| Patio slider replacement | $1,800 - $3,500 installed |
| Bay window replacement | $2,500 - $5,000 installed |
| New construction window installation (per window) | $400 - $800 installed |
| Entry door installation | $1,200 - $2,800 installed |
| Patio door installation | $1,500 - $3,200 installed |
| French door installation | $2,000 - $4,500 installed |
| Storm door installation | $400 - $900 installed |
In Foster City, prices tend to run toward the upper end of these ranges when the opening is out of square and needs framing correction, or when HOA review adds time before work can start. Every Westlight customer receives a written price before any work begins, and that price does not change at the door.
Neighborhoods We Serve in Foster City
We work across all of Foster City, from the lagoon-front townhomes near Gull Park to the tract single-family streets south of Hillsdale Boulevard. Most Foster City homes are within a short drive of our Bay Area dispatch office, so we can usually schedule a visit within a day or two of your first call.
- Dolphin Bay
- Isle Cove
- Whale’s Tail
- Beach Park
- Bay Vista
Service Area – Cities Near Foster City
Westlight Windows & Doors serves Foster City and the wider Bay Area from our San Francisco Bay Area office. If you own property in a neighboring city, we can help there too, including San Francisco, CA, San Jose, CA, and Los Angeles, CA for larger projects. We also cover San Diego, CA for clients with property in both regions.
Serving Foster City, CA - Our Local Coverage Area
We’re based in the Foster City 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 Window Company in Foster City
We’re familiar with the architectural review process used by Foster City’s condo and townhome associations. We can provide product cut sheets, color samples, and specification details to help your HOA application move forward, and we’ll schedule work around any noise-hour restrictions the association imposes.
Most Foster City addresses are a short trip from our Bay Area dispatch office, so we can usually schedule an estimate within a day or two. Calls are answered by a live person 24 hours a day, so you can call (903) 354-7134 any time to get on the schedule.
When a Foster City job requires a permit, we pull it and handle the inspection. That’s part of the written price you receive before work starts. If your project doesn’t require one, we’ll tell you that too and explain why.
If you’re ready to get a written price for window or door work in Foster City, call (903) 354-7134. A real person answers, and your estimate is free.
What happens when you call
- 1A real person answersNo phone trees - talk to a local windows & doors pro.
- 2You get an upfront price rangeHonest numbers before anyone is dispatched. No surprises.
- 3We come out and measureLicensed & insured, at a time that suits you - the visit and the quote are both free.
- 4You get the price in writingLine-itemed, yours to keep, and nothing starts until you say go.
What Foster City Customers Say
"Got quotes from three companies. Westlight wasn't the cheapest but they were the only one who measured everything carefully and put it all in writing. Worth it. No surprises on install day."
- Craig Dillard"Our sliding patio door had come off its track years ago and we just lived with it. New one is smooth as butter. They hauled off the old one and vacuumed up before they left."
- Jessica Landry"Replaced eight drafty old windows that were basically single pane. The house is warmer already and the street noise is way down. Crew was on time both days and the price was exactly the quote."
- Harold Bemis










Before
After
Before
After
Before
After