Free in-home measure and quote - PGT, CGI and CWS impact lines compared on your actual openings, style by style
Windows & Doors Services in Marathon, FL
Replacing windows or doors in Marathon means building for salt, wind, and code, and we’ve seen how those three forces punish a bad install. TruePane Windows & Doors handles residential window and door work from Key Colony Beach to Grassy Key, and a live person answers our phone at (954) 280-4413 at any hour. Whether it’s impact-rated replacement on a 1970s CBS ranch near the airport or a custom slider on an elevated post-Irma rebuild off Sombrero Beach Road, we measure twice, quote on paper, and stand behind the finished opening in writing.
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
Homeowners in neighborhoods like Sombrero Beach and Gulfside Village call us because the houses here are not like mainland houses, and neither are the warranty fights. A window that holds fine in Miami can fog, bind, or corrode within three years in Marathon’s salt air, and the manufacturer will point at the install the moment the seal fails. Our answer is The Keystone Standard: both manufacturer warranty layers registered in writing, durations stated, and a Done Right Promise on the labor. If the pane is not true, the job is not done, and we make it right without making you argue for it.
We’re led by Dale Kessler, a second-generation glazier who started TruePane in 2008 and trained under a rule that has not changed: out-of-true installs and voided warranties are problems worth fixing permanently. The crews you’ll see in Marathon are background-checked, uniformed, and working the way they would in their own mother’s house. We hire local, train apprentices into journeymen, and act like a company that plans to be answering the phone in Marathon in thirty years.
Windows & Doors Services We Offer in Marathon
Window Installation
New-construction and remodel window installation set in Marathon’s concrete block and wood-frame openings, with marine-grade flashing practices called for by Monroe County’s exposure. We quote the manufacturer line side by side on paper so you see exactly what goes into the wall. Learn more about our Window Installation in Marathon.

Door Installation
Entry doors, French doors, and sliders hung square in openings that have often shifted or been rebuilt after elevation work. We set thresholds, weatherstripping, and hardware for salt-spray durability, not just for the showroom look. Learn more about our Door Installation in Marathon.

Window Replacement
Replacement windows for Marathon homes where jalousie frames, fogged seals, or post-Irma rough openings mean standard off-the-shelf units won’t close the way they should. We account for the altered framing we see on lifted and repaired homes throughout the middle Keys. Learn more about our Window Replacement in Marathon.

Impact Windows & Doors
Impact Windows & Doors in Marathon built for the 180+ mph design wind speeds that apply across the Keys, not the lower mainland thresholds. We’re an authorized installer for PGT and CGI, and we register both warranty layers before the truck leaves the driveway.

Energy-Efficient Windows
Energy-Efficient Windows in Marathon with Low-E insulated glass units sized to cut the cooling load on homes running air conditioning against 80% humidity most of the year. The right glass package here pays for itself faster than in drier climates, and we’ll show you the numbers on each line we quote.

Sliding & Patio Doors
Sliding & Patio Doors in Marathon with salt-rated stainless hardware that won’t seize after two hurricane seasons. We replace rollers, tracks, and complete door systems on canal-front and ocean-facing homes alike.

Glass Railing Systems
Glass Railing Systems in Marathon for decks, balconies, and pool areas where water views are the point. Glass specified for coastal exposure, anchored by installers who understand wind load on elevated structures.

Custom Windows & Doors
Fully custom openings for Marathon rebuilds where off-the-shelf sizes simply don’t fit the framing. We measure every opening twice, fabricate to the opening, and warranty the result in writing.

Neighborhoods We Serve in Marathon
TruePane crews work throughout Marathon and the surrounding keys, typically reaching most Marathon addresses the same day a job is scheduled. That includes:
- Sombrero Beach and Sombrero Beach Road
- Gulfside Village and the area around Marathon Community Park
- Key Colony Beach and Coco Plum Beach
- Grassy Key and the properties along Gulfview Avenue
- Boot Key and the canal-front streets off Aviation Boulevard
Why Marathon’s Climate & Housing Affect Windows & Doors
Marathon sits entirely surrounded by open water, flanked by the Atlantic and the Gulf at the same time. That means salt spray hits window frames, sill pans, and door hardware from multiple directions every month of the year, not just during storms. Aluminum corrodes faster here than in almost any coastal mainland market, and standard inland hardware will seize or pit within a few seasons. Marine-grade finishes and stainless components are not an upsell on Marathon homes. They are the only way a window or door survives long enough to honor its warranty.
The housing stock compounds the problem. Most of Marathon’s residential buildings are elevated CBS or wood-frame homes from the 1950s through the 1980s, many still carrying original jalousie or louvered awning windows that fail current Monroe County impact requirements outright. Hurricane Irma’s Category 4 direct strike in 2017 destroyed enormous amounts of housing, and much of what stands now is post-disaster rebuild or FEMA-elevation retrofit, often with rough openings that were altered during the lift. That creates non-standard framing conditions a mainland install crew won’t recognize, and it’s one reason we measure every rough opening twice and quote to the actual existing frame, not to a catalog assumption.
Pricing for Windows & Doors in Marathon
Marathon window and door pricing starts higher than mainland Florida because the products themselves must meet Monroe County’s stricter impact-rating and corrosion-resistance standards. Here’s where most jobs land:
- Single impact window replacement: $1,200-$3,400 installed, depending on size and manufacturer line.
- Full-home impact window replacement (10-15 openings): $18,000-$42,000 for elevated single-family homes.
- Sliding glass door replacement: $3,500-$9,000 for impact-rated, salt-specified systems.
- Full custom openings or post-elevation reframing work: quoted per opening after on-site measurement, never as a square-foot guess.
Every quote is line-itemed on paper before any work begins, with manufacturer line, glass package, hardware finish, and both warranty layers listed. No surprise line items on the bill. Call (954) 280-4413 for an exact quote, and ask about the standing a free written repair estimate, the maintenance check, and the permanent 5% discount for seniors and veterans.
Service Area - Cities Near Marathon
Beyond Marathon proper, TruePane serves homeowners across the middle and upper Keys. We regularly work in Key Colony Beach, Big Pine Key, Tavernier, and Key Largo, bringing the same written warranty registration and Done Right Promise to every job.
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
Yes. Marathon sits inside a 180+ mph design wind speed zone, and Monroe County effectively requires impact-rated windows and doors on every permitted structure. The moment you pull a permit for even a minor renovation, inspectors flag non-compliant openings, and original jalousie windows are the first ones called out. A permitted remodel frequently turns into a full impact window replacement. Call (954) 280-4413 and we’ll walk you through what your specific home will trigger.
Most full-home impact replacements in Marathon run between $18,000 and $42,000 for 10 to 15 openings, depending on the manufacturer line and the condition of the rough openings. Homes lifted after Irma often carry altered framing that adds per-opening labor. We quote line by line on paper, no square-foot guessing. Call (954) 280-4413 for a fixed written estimate.
Only if the frame finish and hardware are specified for marine exposure, and only if the install prevents water intrusion from day one. We specify marine-grade finishes and stainless hardware on Marathon jobs, register both manufacturer warranty layers in writing, and back the labor with our Done Right Promise. If the pane is not true, the job is not done, and we make it right.
In most Marathon homes, yes, once the permit is open. Monroe County inspectors treat jalousie and louvered awning windows as non-compliant openings, and a permit on any part of the house gives them a reason to flag every one. We see this constantly on 1950s-1970s CBS homes off Sombrero Beach Road and Gulfview Avenue. The practical move is to plan the replacement budget before the inspector requires it. Call (954) 280-4413 and we’ll help you sequence the work.
Most standard window and door replacements in Marathon are completed in a single visit once the units arrive, typically a full day for multiple openings. Custom fabricated units add lead time from the manufacturer, and post-elevation reframing work extends the schedule. We’ll give you a written timeline with the quote and stick to it. Call (954) 280-4413 to schedule a measure, and we’ll start with the estimate, not the sales pitch.
Written by Dale Kessler, Owner at TruePane Windows & Doors, serving Marathon and the Florida Keys through a craft tradition that refuses to let an out-of-true install leave a customer’s home.
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
"Storm door and a new back entry door. Small job, but they treated it like one that mattered. Screws in the hinges are stainless, the sweep actually seals, and the invoice matched the phone quote to the dollar."
- Vernon H."Whole-house window replacement at 71 years old is not something you want to do twice. Dale walked the house himself for the quote. Crew was the same three men all four days, and the foreman knew every window by room."
- Pat and Ray L."Eleven windows replaced in two days. The crew chief, Marcus, showed me the level on every single frame before they caulked it. My wife noticed the street noise was gone before I did."
- Ronald P.



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