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
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AfterWindows & Doors Services in Marathon, FL
Marathon sits squarely inside Florida’s High Velocity Hurricane Zone, which means every window and door on the island answers to the most demanding wind-load code in the country. We work in that reality every day. TruePane Windows & Doors installs, replaces, and services Impact Windows & Doors in Marathon, entry doors, sliding glass doors, and custom glazing throughout the area, from Sombrero Beach to the Grassy Key flats. If you’re pricing out a window or door job, call (754) 238-2201 and you’ll reach a live person who can talk through your specific opening, your specific exposure, and what the permit office will want to see.
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.
Why Marathon Homeowners Choose TruePane Windows & Doors
Most of our Marathon customers have been in their homes for twenty years or more. They’ve already learned the difference between a bid that holds up and one that doesn’t. Dale Kessler founded TruePane in 2008 on a rule that still governs every job: if the pane is not true, the job is not done. That’s not a slogan. It’s the reason we measure every opening twice, register both manufacturer warranty layers in writing before the truck leaves the driveway, and stand behind the work with a Done Right Promise that no one has to argue over.
We’ve worked in Key Colony Beach and along the Coco Plum corridor and up through the older CBS neighborhoods off Overseas Highway. What we hear again and again is that the crew showed up on time, in uniform, background-checked, and left the job site cleaner than they found it. No surprise line items. No second appointment left hanging. We’ll be there when we say, and the work is done right the first visit.
Windows & Doors Services We Offer in Marathon
Window Installation
New construction or whole-home replacement, framed and set to Marathon’s HVHZ standard. We cut rough openings, shim precisely, and flash for salt-driven rain on all four sides.
Learn more about our Window Installation in Marathon.
Door Installation
Entry doors, French doors, and impact-rated front doors hung square and sealed against wind and salt air. A door that binds in July is a door that wasn’t set right.
Learn more about our Door Installation in Marathon.
Window Replacement
Most older Marathon homes still carry original jalousie windows, which are completely non-compliant with current code. We replace them with certified impact units sized to the opening, including the concrete cutting and block infill that jalousie retrofits demand.
Learn more about our Window Replacement in Marathon.
Impact Windows & Doors
We install impact-rated windows and doors from PGT, CGI, and CWS, every unit carrying a Miami-Dade Notice of Acceptance. If you’re in Marathon, HVHZ compliance is not optional, and we don’t sell anything less.
Energy-Efficient Windows
Marathon’s 90-degree afternoons and 85 to 95 percent humidity put a constant load on your cooling system. Low-E glass, insulated frames, and proper sealing cut that load measurably, and we quote Energy-Efficient Windows in Marathon glass packages side by side on paper.
Sliding & Patio Doors
Salt air corrodes rollers, tracks, and hardware faster here than almost anywhere on the mainland. We replace Sliding & Patio Doors in Marathon with marine-grade hardware rated for the exposure and set the track so the door moves with two fingers, not two hands.
Glass Railing Systems
For elevated decks and water-facing balconies, we install Glass Railing Systems in Marathon that are tempered and impact-rated, meeting Monroe County standards and holding their clarity in constant salt spray.
Custom Windows & Doors
Odd openings, round tops, oversize sliders, and work that requires a custom fabricated unit. We don’t force stock sizes into openings that were never stock to begin with.
We also handle the home basics right the first time, which means no callback for a fogged seal or a misaligned latch.
Neighborhoods We Serve in Marathon
We cover the entire island and the surrounding keys. Typical response time for a scheduled estimate in Marathon is same-week, and for an emergency board-up or storm-prep call we get someone out as quickly as the causeway allows.
- Sombrero Beach
- Coco Plum
- Key Colony Beach
- Grassy Key
- Knights Key
Why Marathon’s Climate & Housing Affect Windows & Doors
Marathon is a narrow coral-limestone island with the Atlantic on one side and Florida Bay on the other. There is no inland buffer. Every window and door on every facade takes direct salt air, 360 degrees, year after year. Aluminum frames, fasteners, and hardware corrode noticeably faster here than they do in mainland coastal cities, which is why we specify marine-grade hardware on every exterior opening and recommend inspection cycles measured in years, not decades.
Then there’s the housing stock. Most of the island’s surviving homes were built in the 1950s through the 1970s as mid-century concrete block, framed around the slim profile of jalousie windows. When those get swapped for modern HVHZ impact units, the rough openings are almost always the wrong size. Concrete cutting and block infill are routine here. Monroe County inspectors look specifically at that work during the permit close-out, and we’ve done enough of it to know exactly how they’ll measure.
Hurricane Irma reshaped this island in 2017. Since then, every window and door replacement in Marathon must carry a Miami-Dade Notice of Acceptance for HVHZ compliance. That’s a certification tier above the standard impact-rated products legal farther up the coast. The product selection and the permitting process here are simply different from any mainland market.
Pricing for Windows & Doors in Marathon
Window and door pricing in Marathon runs higher than mainland Florida, and for honest reasons. HVHZ-certified units carry a real cost premium, and the concrete cutting and block infill that jalousie retrofits require add labor no mainland job ever sees. Here’s what homeowners should expect as of 2025:
- Standard impact window replacement: $1,200-$2,800 per opening, installed
- Impact entry door replacement: $3,500-$7,500 depending on size and swing
- Sliding glass door replacement: $4,000-$9,000 for a typical 8-foot opening
- Jalousie-to-impact retrofit with concrete work: add $400-$1,000 per opening
- Glass railing systems: $380-$650 per linear foot, installed
We give written, line-item quotes. The number on the proposal is the number on the bill. Call (754) 238-2201 for an exact figure on your openings, and ask about the maintenance check if your existing windows and doors just need attention rather than replacement.
Service Area - Cities Near Marathon
TruePane serves all of the Middle Keys and beyond. We work regularly in Key Colony Beach, down through Big Pine Key, and up the Overseas Highway through Tavernier and Key Largo. Dispatch and scheduling are coordinated from our South Florida office, and our crews live and work locally in the Keys.
Serving Marathon, FL - Our Local Coverage Area
We’re based in the Marathon 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 Windows & Doors in Marathon
In Marathon you need HVHZ-compliant windows and doors carrying a Miami-Dade Notice of Acceptance. Regular impact-rated products legal elsewhere in Florida will not pass Monroe County permitting. We only install units with the NOA documentation, and we register both warranty layers before we leave the driveway. Call (754) 238-2201 and we’ll confirm what your specific openings require.
Most jalousie-to-impact retrofits run between $1,600 and $3,800 per opening once you account for the wider rough opening, concrete cutting or block infill, and the cost of the certified unit itself. The exact number depends on your block thickness and how the original frames were set. Estimates are free and written line by line.
No. We quote fixed prices from a written proposal, and we don’t file change orders unless you ask us to expand the scope. If we find something behind the wall, we stop and show you before any additional work is priced. That’s a square deal, and it’s the only way we work.
Yes. Monroe County permitting is part of every Marathon job we do. We handle the application, the NOA documentation, the inspections, and the close-out. You shouldn’t have to become a code expert to replace a window, and with us you won’t.
If you have existing shutters, we can inspect and service them quickly. If you need permanent impact protection, the time to install it is before a storm is on the radar, not after. Either way, call (754) 238-2201 and a live person will answer, day or night.
Call TruePane Windows & Doors in Marathon
For a free, written estimate on windows or doors in Marathon, call (754) 238-2201. You’ll talk to a person who knows the island, knows the code, and will give you a straight answer. We stand behind the work, in writing, every time.
Written by Dale Kessler, Owner at TruePane Windows & Doors, serving Marathon with craft, code-compliant installs, and a Done Right Promise on every job.
Six Reasons Homeowners Choose TruePane 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.
Other TruePane Windows & Doors Services
What Neighbors Say About TruePane Windows & Doors
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 Marathon Customers Say
"Our bay window had rotted at the sill and two other outfits wanted to talk us into a flat picture window instead. TruePane rebuilt the opening and matched the original look. Neighbors have knocked on the door about it."
- Gene A."French doors to the patio, custom size because this house was built in 1961 and nothing is standard. Measured twice, three weeks to fabricate like they warned, and the install day they laid runners over my floors without being asked."
- Marie S."A casement crank had stripped and the sash was swollen shut. The technician, Ray, fixed the crank on the spot and only then talked about replacement for the three windows that were genuinely done. That is why the whole street uses them now."
- Eleanor G.