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Therma-Tru Window Replacement: The Westchester Owner’s Guide
Therma-Tru window replacement in Westchester typically runs $450 to $1,800 installed per window, depending on the series, glass package, and whether the frame itself needs rebuilding. We stock common Therma-Tru hardware, sashes, and glass units on our trucks, so most Westchester replacements happen same-day once we confirm your measurements. Most owners find out something’s wrong when a window won’t latch, the glass fogs between panes, or a crank spins without moving the sash. Ed Winslow has seen it plenty of times in Westchester homes, especially the older ranches off Bird Road where original Therma-Tru units have logged fifteen-plus Florida summers.
Which Therma-Tru Models This Applies To
Therma-Tru builds several window lines, and the replacement approach differs by series. The Classic-Craft and SlimLine series are common in Westchester homes, and each uses slightly different sash profiles and hardware spacing. Here’s the compatibility gotcha we run into constantly: Therma-Tru embeds a product ID on a sticker inside the frame channel, usually on the top or left side of the sash. If that sticker is gone, you need the glass dimensions and the sash thickness to match the correct part. Guessing based on a photo of the outside trim rarely works.
On the OEM versus aftermarket question, our honest take: OEM Therma-Tru parts are worth it for seals, weatherstripping, and sash locks where tolerances matter. Quality aftermarket equivalents exist for balances and shoe springs, and we use them when they genuinely match spec. We’re an independent service provider, not affiliated with Therma-Tru, so we choose parts based on what will last in Westchester’s salt-tinged air and afternoon thunderstorms, not on a brand requirement. We also stock parts for PGT, CGI, and CWS windows, which helps when a Westchester home has mixed brands across different rooms.
Signs Your Therma-Tru Window Replacement Is Failing
- Fog or haze between the glass panes. The seal on the insulated glass unit has failed, and Florida humidity is now condensing inside. This is not cleanable. The glass unit gets swapped, not the whole whole frame.
- The sash won’t stay up or drops hard. The balance shoes or spring mechanisms have worn out. Therma-Tru sashes are heavier than people expect, and a failing balance is not just annoying, it’s a finger-pinch waiting to happen.
- You can hear more street noise than you used to. Weatherstripping has compressed or the sash is no longer seating tight. Westchester’s traffic off the Palmetto makes this noticeable within a week of failure.
- The crank turns but the window barely moves. The gearbox inside the operator is stripped. This is especially common on casement and awning styles that get opened daily for the sea breeze.
- Visible rot or softness at the sill corners. Water has been getting past the seal. In Westchester’s rainy season, this spreads fast, and it usually means you need more than just a part, you need the sill rebuilt before a new sash goes in.
Replacement Cost & What’s Included
In Westchester, here’s what we typically see for installed Therma-Tru window replacements:
- Glass unit only (seal failure): $250-$550 per window
- Sash replacement (hardware issue): $400-$900 per window
- Full unit replacement (frame damaged): $900-$1,800 per window
What moves the price: window size, glass package, whether the frame needs rebuilding, and how many windows you’re doing at once. Every estimate we give in Westchester is a written line-item quote, upfront. No change orders down the road. The labor, the part, the cleanup, the haul-away, it’s all on the page before you say yes. And everything we install is covered by our 36500-Day Done Right Promise. If it’s not done right, Ed makes it right, period.
DIY or Call Us?
You can safely check a few things yourself: whether the window is square in the opening, whether the weep holes are clogged with dirt, whether the caulking around the exterior frame is cracked. That’s diagnosis. The actual replacement work on a Therma-Tru window involves tensioned balances, sharp glass edges, and sashes that weigh more than they look like they should. A sash that drops while you’re working on it can break a finger or worse. We’ve fixed enough DIY attempts in Westchester to say this plainly: the money saved rarely covers the repair. If you’d rather have it done right the first time, call (863) 251-5864. We’ll send a technician who does this every week, not someone who watched a video and guessed.
FAQs
A Therma-Tru window in Westchester’s climate lasts 15 to 25 years depending on sun exposure and how well the frame was maintained. Windows on the south and east faces fail faster because of morning and midday sun heating the seals. Call (863) 251-5864 for a free assessment of your specific windows.
Yes, if the problem is a worn balance, a stripped operator, or failed weatherstripping, we repair the existing sash without touching the frame. If the glass seal has failed or the frame has rot, replacement is the honest answer. We’ll tell you which one you need before we touch anything.
Most single-window glass or sash replacements take one to three hours once we’re on site. Full frame rebuilds can take half a day. We schedule around Westchester homeowners’ workdays and never leave a window opening exposed overnight.
We stock common Therma-Tru balances, shoe springs, weatherstripping, sash locks, and certain glass units sized for South Florida code. Odd sizes and special glass packages take two to five business days to source. We confirm parts availability before we schedule so you’re not waiting around.
If your Therma-Tru windows are showing their age, don’t let a small part failure turn into a frame rebuild. Call (863) 251-5864 for a free estimate. A real person answers, 24 hours a day. We’re the one down the road.
Written by Ed Winslow, Owner, Winslow Windows & Doors at Winslow Windows & Doors, serving Westchester and nearby areas.
Six Reasons Homeowners Choose Winslow Windows & Doors
Impact systems engineered to design pressures up to +/-100, matched to your wind zone - your openings hold when the storm arrives.
Low-E insulated impact glass from our manufacturer lines commonly cuts monthly cooling bills 20-30%.
Laminated impact glass shuts out up to 40% of outside noise - traffic, neighbors, weather.
Monitoring services run $30-90 a month. Laminated impact glass resists forced entry around the clock, with no subscription.
Florida homeowners average around 25% savings on the windstorm portion of their policy after protecting every opening - some homes qualify for more.
A full impact package upgrades curb appeal, buyer confidence and appraised value in one project.










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