Free in-home measure and quote - PGT, CGI and CWS impact lines compared on your actual openings, style by style
Sliding glass doors
Impact garage doorsPGTCGI
Before
After
Before
After
Before
AfterFast, Reliable Window Replacement Across San Marcos
Window replacement in San Marcos, TX typically runs $600-$1,400 per window for insert replacements and $900-$2,200 per opening for full-frame work, depending on glass package, frame material, and whether Chapter 7A fire-rated glazing applies to your street. Most San Marcos homes we see were built between 1988 and 2005, and that matters: the builder-grade vinyl windows those tracts went up with are now failing en masse from the inland valley’s brutal thermal cycling. We schedule estimates across San Marcos every week, and crews arrive with manufacturer spec sheets on paper so you see exactly what you’re buying before any work begins. Call (888) 635-0804 to set up a free estimate.
If you live in a 1990s stucco tract home anywhere from Twin Oaks Valley down to the flatter neighborhoods near San Marcos Creek, you’ve probably noticed fog creeping between the panes on more than one window. That’s not coincidence. That’s seal failure happening on a subdivision-wide timeline. Our Window Replacement team deals with it every week in San Marcos, and we’ve learned that a window built for coastal San Diego conditions simply will not survive here the same way.
Why TruePane Windows & Doors Is San Marcos’s Preferred Window Replacement Company
TruePane was founded by second-generation glazier Dale Kessler in 2008, and the whole operation runs on one rule Dale keeps on the whiteboard: if the pane is not true, the job is not done. That’s not marketing language. It’s a trade standard that dictates how every opening gets measured twice, how every flashing detail gets checked behind the old frame, and how every warranty gets registered before the truck leaves your driveway. Homeowners in San Marcos who’ve been burned by a fogged seal and a contractor who stopped answering the phone tend to appreciate that.
The San Marcos work we do is covered by our Done Right Promise under The Keystone Standard. Both manufacturer warranty layers get registered in writing, with durations stated, before we leave the job. If something isn’t right within 90 days, we make it right. No paperwork fights, no arguing. That promise applies to every full-frame replacement, insert job, and energy-efficiency upgrade we do in the 92069 and surrounding San Marcos neighborhoods.
We’ve been serving local communities since 2008 through a heritage that started well before the company was formally founded. TruePane hires local, trains apprentices into journeymen, and acts like a company that plans to be in town in thirty years. When a live person answers our phone 24 hours a day, seven days a week, that’s the same crew culture showing up. Background-checked, uniformed technicians measure every opening twice and quote manufacturer lines side by side on paper. No voicemail trees. No callback forms. You call, a person answers.
Our Window Replacement Services in San Marcos
Full Frame Replacement
Full-frame replacement means we pull the entire old window, frame and all, down to the rough opening. For San Marcos homes built in the 1990s, this is often the right call because it’s the only way to inspect and repair the flashing that builders frequently installed wrong or skipped entirely. In the Twin Oaks Valley corridor, our crew replaced two second-story west-facing Milgard vinyl sliders in a 1998 stucco tract home where fog between the panes confirmed argon loss from seal failure. We discovered the original head flashing was missing on both openings, so we installed full-frame replacements with stainless steel flashing tape, fusion-welded frames, and low-E/argon insulated glass units rated for Chapter 7A fire zones. The job passed inspection the first time. That’s what happens when you can actually see the rough opening before the new window goes in.
Insert Window Replacement
Insert replacement keeps your existing frame and fits a new window inside it. It’s less invasive and typically runs $100-$300 less per opening than full-frame. But here’s the San Marcos-specific truth: inserts only make sense when the original frame is still square, flashed correctly, and dry. If you have water stains developing on drywall below a second-story window, or if the old builder flashing tape has peeled back behind the stucco, an insert will cover the problem without fixing it. We’ll tell you which route is honest for your opening, and we’ll show you why on paper before you spend a dollar.
Storm Window Replacement
Storm windows in San Marcos are less about hurricane protection and more about what Santa Ana winds do to west- and south-facing elevations. Sustained positive pressure during wind events pushes water and air hard against rough openings, and original 1990s builder flashing tape typically peels or fails under that repeated load. We carry storm-rated replacement packages that account for those pressure differentials, and we always verify that the rough opening gets sealed properly before the new window goes in. The cheap builder work from thirty years ago simply was not built for the wind loads this valley sees.
Energy-Efficient Upgrade
Replacing fogged dual-pane windows with modern low-E/argon insulated glass units is the single biggest improvement most San Marcos homeowners make to their cooling bills. Summer highs here routinely top 100°F while overnight lows drop into the 50s, and that 40-50°F daily swing drives heat gain through degraded seals all afternoon. A properly specified low-E package cuts that solar gain dramatically. The difference between an inland-spec window and one specified for San Marcos’s thermal cycling is measurable within the first summer, and we can show you the glass performance numbers side by side.
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 San Marcos
We’re an authorized installer for more than a dozen manufacturer lines, including, PGT, CGI, and ES Windows. For San Marcos’s fire-zone neighborhoods, we stock and quote PGT and CGI lines with Chapter 7A-rated glazing, and we also carry ES Windows for homeowners in the Twin Oaks Valley corridor who want custom sizing on second-story replacements. Every quote we give you lists manufacturer options side by side on paper, with the glass package, frame material, and warranty duration spelled out. You see exactly what you’re buying, and you don’t get pushed into a house brand that gets marked up by the installer.
Common Window Replacement Problems We See in San Marcos Homes
- Simultaneous seal failure across whole subdivisions. Fusion-welded vinyl frames from the late 1990s expand and contract so aggressively during San Marcos’s 40°F daily swings that the sash jamb and insulated glass unit seals crack within 15-20 years. When one house on the street fogs, the neighbors are usually right behind it.
- Peeled builder flashing behind stucco. Santa Ana wind events push sustained positive pressure against west- and south-facing rough openings. Original builder flashing tape from the 1990s typically peels or fails, letting water run down inside stucco walls behind second-story windows. The first sign is often a water stain on the ceiling below.
- Fire-zone replacement failures. In Very High Fire Hazard Severity Zones like Twin Oaks Valley, replacement windows without Chapter 7A fire-rated glazing fail final inspection. That’s a costly re-do that coastal contractors almost never encounter, and it catches homeowners off guard mid-project.
- Improper frame sizing on builder-grade 6/0 sliders. The standard 6/0 sliding glass doors and vinyl dual-pane windows installed throughout San Marcos’s stucco tracts were manufactured to loose tolerances. When we measure twice and compare to the rough opening, we frequently find the original frame is racked or undersized, which means an insert won’t seat correctly. Full-frame replacement solves it.
Pricing for Window Replacement in San Marcos, TX
Insert window replacement in San Marcos typically runs $600-$1,400 per window. Full-frame replacement runs $900-$2,200 per opening, with second-story work and Chapter 7A fire-rated glazing pushing toward the upper end. A standard 1990s stucco home with 12 windows and two sliders will usually land between $12,000 and $26,000 for a full-house project. The coastal-spec version of the job costs less up front. The inland-spec version costs less over ten years. Cheap vinyl frames without fusion-welded corners and proper low-E/argon glass will fog again within a decade in this valley. We quote manufacturer lines side by side so you can see the actual price difference before deciding. Call (888) 635-0804 for a free written estimate with no line-item surprises.
We Also Serve Cities Near San Marcos
Our crews regularly work in Driftwood, Buda, Manchaca, and Kyle, and we know the housing stock and fire-zone boundaries across the whole Hays County corridor. If you’re outside San Marcos proper but still dealing with 1990s builder windows, call us. We’ll bring the same no-hassle upfront pricing and the same Done Right Promise.
Serving San Marcos, TX - Our Local Coverage Area
We’re based in the San Marcos 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 San Marcos
Those tract homes were built with builder-grade dual-pane vinyl windows that used fusion-welded frames and early-generation insulated glass units. San Marcos’s inland valley thermal cycling, with summer highs over 100°F and overnight lows in the 50s, expands and contracts those vinyl frames daily. That repeated stress cracks the sash jamb and glass unit seals within 15-20 years, which is why entire subdivisions now show fogged windows on the same schedule. The windows didn’t all fail at once. They hit their design failure point at once. Call (888) 635-0804 and we’ll tell you which of your windows are worth replacing versus repairing.
Yes, if your home falls within a mapped Very High Fire Hazard Severity Zone, which includes parts of the Twin Oaks Valley corridor and other hillside and canyon-adjacent neighborhoods in San Marcos. California Building Code Chapter 7A requires multi-pane tempered or fire-rated glazing on any permitted window or door replacement in those zones. A contractor who misses this will fail final inspection and you’ll pay for a re-do. We check fire-zone mapping on every San Marcos estimate before we quote, and we carry PGT and CGI lines that meet Chapter 7A. Call (888) 635-0804 for an exact quote on your street.
The most common problem is missing or failed head flashing above the original window opening. Builders in the late 1990s frequently skipped flashing tape entirely or used a product that peels under Santa Ana wind pressure. Water then runs down behind the stucco and shows up as stains on the ceiling below the window. When we pull the old frame during a full-frame replacement, we install stainless steel flashing tape and correct the rough opening so water stays on the outside. An insert replacement can’t fix this because the damaged flashing remains hidden behind the old frame.
Full-frame. Water stains below second-story windows in a 1990s San Marcos stucco home almost always mean the original head flashing has failed or was never installed. An insert replacement fits inside the existing frame and leaves that failed flashing in place, which means you’ll be paying for the same leak again in a few years. Full-frame replacement lets us pull the whole frame, inspect the rough opening, repair the flashing correctly, and then set a new window that will actually stay dry. It costs more up front, and it’s the honest call for that condition. Call (888) 635-0804 and we’ll walk you through what we see on your specific openings.
Yes. Fogged dual-pane windows have lost their insulating gas, which means the glass unit is now performing close to a single pane. In San Marcos, where summer afternoons routinely top 100°F and overnight lows drop into the 50s, that thermal cycling is what drives your cooling load. Replacing failed dual-pane units with modern low-E/argon insulated glass cuts solar heat gain and slows nighttime heat loss, which reduces how hard your AC runs. The savings are larger here than in coastal cities because the temperature swings are larger. The exact dollar figure depends on your window count and orientation, but the physics of the valley’s thermal load is clear. Call (888) 635-0804 for a free estimate and we’ll give you glass performance numbers side by side.
Written by Dale Kessler, Owner at TruePane Windows & Doors, serving San Marcos since 2008.