Free in-home measure and quote - PGT, CGI and CWS impact lines compared on your actual openings, style by style
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AfterFast, Reliable Window Replacement Across Los Altos
Window replacement in Los Altos typically runs $900-$2,400 per opening for insert replacements and $1,400-$3,800 for full-frame work, depending on the product line and whether the opening needs structural correction. Most projects we quote in Los Altos take two to four days to install, with the measured survey and written price completed before any tool is lifted. We know the specific failure patterns of the 1950s-1970s ranch stock here, and we schedule crews out of our San Francisco Bay Area office to serve Los Altos directly. Call (509) 265-6387 to get a written price, not a ballpark.
Why Sightline Windows & Doors Is Los Altos’s Preferred Window Replacement Company
Sightline Windows & Doors has installed 18,000+ windows and doors since 2012, every one under the Haven Standard. That means the measured survey you keep is the same document as the written quote. No separate sales visit. No re-priced change order after the work begins. For Los Altos homeowners researching contractors before they call, that distinction matters more than how long a company has been around.
Our technicians are background-checked, uniformed, and identified by license number before arrival. That’s Haven Clause 3, Verified Crews, and it means the person at your door in Los Altos is the person on the record. We don’t use subcontractors. The crew that measures your windows is the crew that installs them.
When a Los Altos homeowner brings us a competitor’s written estimate, we’ll review it at no charge. If our number is higher, we’ll show you exactly why, in dollars, on the same line items. Most people who see both documents side by side stay with us because the price was never the problem. The vagueness was.
Our Window Replacement Services in Los Altos
Full Frame Replacement
Full frame replacement means the entire existing window, including the frame and trim, comes out and a new unit is set into the rough opening. In Los Altos, this is the service we recommend for the original aluminum single-pane sliders on postwar ranch homes, because the frames themselves are usually corroded at the corners and the rough openings need shimming and flashing corrections that an insert can’t address. We measure the opening, document the condition with photos, and give you a written scope that cannot change once signed. Expect full frame work in Los Altos to run $1,400-$3,800 per opening, with the higher end covering wood-clad and fiberglass units specified by performance tier, not by what’s in stock.
Insert Window Replacement
An insert, sometimes called a pocket replacement, fits a new window into the existing frame. It’s the right move when the frame itself is still sound and square, which we see most often on Los Altos homes that had partial upgrades in the 1990s or early 2000s. Inserts preserve interior trim and reduce labor, so pricing lands lower: typically $900-$2,400 per window in Los Altos. We’ll tell you honestly if your frames are too far gone for this option. About a third of the Los Altos homes we survey that ask for inserts actually need full frame work instead, and we document why with frame readings and photos you keep.
Vinyl Replacement Windows
Vinyl is the budget-conscious choice, and we do install it, but it’s not what most Los Altos projects call for. The housing stock here is saturated with ranch homes being renovated to a much higher specification, and vinyl’s thermal expansion in our dry summers tends to underperform the fiberglass and wood-clad lines we specify more often. A straight vinyl insert in Los Altos runs $900-$1,600 per window. If you’re on a tighter budget and want the written price to reflect that, we’ll show you exactly what you give up in U-factor and SHGC performance before you commit.
Energy-Efficient Upgrade
Every permit-pulled window replacement in Los Altos must meet California Title 24 energy compliance, which means documented U-factor and SHGC values on the product you’re buying. Our measured survey includes those specs in writing, and the final invoice matches the survey. For Los Altos specifically, solar heat gain matters more than brute insulation, because summers are warm but rarely punishing and the morning marine layer condenses on old single-pane aluminum even in mild weather. We typically specify SHGC in the 0.25-0.30 range for west-facing openings in Los Altos and slightly higher for east-facing glass that benefits from morning warmth. Energy-efficient replacement packages here run $1,200-$3,200 per opening depending on frame material and glazing.
What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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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.
BeforeAfterTrusted Brands We Service in Los Altos
We install from eight manufacturer lines, including PGT, CGI, CWS, and ES Windows, specified by what the opening requires rather than what’s easiest to source. For Los Altos ranch homes where the original aluminum sliders are failing, we often specify ES Windows for their European lift-and-slide systems and PGT for impact-rated packages when the home sits on a lot with significant western exposure. We keep a working inventory of the parts and profiles these manufacturers require for Los Altos’s dominant architectural vocabulary, which means we’re not ordering blind and hoping the lead time works out. When you call, we can tell you in writing what the product costs, what it costs to install, and when it ships.
Common Window Replacement Problems We See in Los Altos Homes
- Corroded aluminum sliders on postwar ranch homes. The original single-pane aluminum sliders installed on 1950s-1970s ranch homes in Los Altos are now 50-65 years old, and the frame corners are corroding where the marine layer moisture settles. Once the frame fails, inserts are no longer viable. We see this on nearly every survey in neighborhoods like Woodland Acres and North Los Altos.
- Backyard sliding glass doors that won’t roll. The 1960s-era 6- or 8-foot aluminum slider is the single most common failure point we encounter in Los Altos. The original track corrodes into the concrete threshold because of the alkaline soils, and the rollers were discontinued decades ago. Repair is almost never economical. This is also covered by our Door Installation in Los Altos service.
- Sill rot from morning marine layer condensation. Los Altos sits inland enough to escape heavy coastal fog, but the morning marine layer still condenses visibly on aged single-pane aluminum frames, and that moisture sits on the interior sill. Over years, the result is soft wood and peeling paint at the sill, which we document with photos before recommending full frame replacement.
- Renovations that outpace the original windows. Los Altos has seen a wave of teardowns and custom rebuilds, and we regularly see homeowners who have remodeled an entire interior but left the original aluminum windows in place. The visual and thermal mismatch is the issue, and the fix almost always requires new-construction window packages rather than inserts, because the rough openings have been re-framed during the renovation.
Pricing for Window Replacement in Los Altos, CA
Here’s what we’re actually quoting in Los Altos today. A single insert replacement in a standard 3-foot-by-5-foot opening runs $900-$2,400. Full frame replacement on the same opening runs $1,400-$3,800. A 6-foot sliding glass door replacement, the most common project in Los Altos, runs $2,800-$6,500 installed. Factors that move the number: frame material, glazing package, Title 24 documentation requirements, and whether the rough opening needs structural correction. You get the written price before we start, and that price cannot change unless you change the scope. Haven Clause 1, Have it in writing, is the whole point. Call (509) 265-6387 for your measured survey and written estimate.
We Also Serve Cities Near Los Altos
Our Window Replacement team covers the full mid-peninsula corridor. We serve Mountain View, Palo Alto, Menlo Park, and Sunnyvale with the same measured survey and written price process, and same-week scheduling is typical. If you’re in Los Altos but your project is in a rental property in one of those cities, we can handle both scopes under one written estimate.
Serving Los Altos, CA - Our Local Coverage Area
We’re based in the Los Altos 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 - Window Replacement in Los Altos
We schedule measured surveys in Los Altos within three to five business days, and the written price is delivered at the end of that visit, not later. Call (509) 265-6387 and a live person will schedule the survey. We don’t route to a voicemail queue.
Yes. We work across Los Altos, from North Los Altos and Woodland Acres to the Country Club area and South Los Altos. The housing stock shifts block by block, from original ranch homes to new-construction replacements, and we survey each property individually.
Yes, typically 10-20% above Mountain View or Sunnyvale, because Los Altos projects skew toward full frame work, wood-clad and fiberglass products, and Title 24 documentation for every permit-pulled replacement. A straightforward vinyl insert is roughly the same price as neighboring cities. The difference shows up in what gets specified.
Yes. Every replacement that requires a permit in Los Altos gets the U-factor and SHGC documentation from us in writing, and the measured survey you keep includes those specs. We work with the Los Altos Building Department process directly. The paperwork travels with the job.
Every job is covered by our 365-Day Done Right Promise: if it’s not done right, we make it right, and that’s written into the Haven Standard, not offered as a courtesy. Manufacturer warranties on PGT, CGI, CWS, and ES Windows products are documented and transferred to you in writing. Call (509) 265-6387 to get the full warranty scope in writing with your estimate.
Get a Written Price for Window Replacement in Los Altos
If you’re researching contractors, you want the price on the page and the details in writing before anyone touches a window. That’s how we work. Call (509) 265-6387 to schedule your measured survey in Los Altos. You’ll get a written line-item price, a documented photo record of what we find, and the same crew from measurement to install. Sonia Raman leads our team, and she’ll make sure the document you sign matches the work we do.
Written by Sonia Raman, Owner at Sightline Windows & Doors, serving Los Altos since 2012.