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AfterFast, Reliable Window Replacement Across Marathon
Window replacement in Marathon means one thing before anything else: every unit has to meet Monroe County’s High-Velocity Hurricane Zone code. No exceptions. If a window doesn’t carry a Miami-Dade Notice of Acceptance, it doesn’t belong in your house. We’ve been replacing windows in Marathon long enough to know that salt air attacks every elevation at once, that canal-front homes rot from below as fast as from the sides, and that homeowners want a written price before anything gets ordered. Call (813) 320-9346 and we’ll measure, spec, and quote your windows in a single visit. We won’t sell you glass that can’t pass inspection.
Why TruePane Windows & Doors Is Marathon’s Preferred Window Replacement Company
Dale Kessler founded TruePane in 2008 on a rule that still governs every install: if the pane is not true, the job is not done. That matters in Marathon, where a window that’s out of square by a quarter inch becomes a water leak by August. Our crews know the difference between a mainland install and a Keys install because we’ve done both, and we spec accordingly.
TruePane carries the 90-Day Done Right Promise and The Keystone Standard on every Marathon job. Both manufacturer warranty layers get registered in writing before our truck leaves your driveway. Durations are stated on paper, not implied. If something isn’t right in those first 90 days, we make it right. No paperwork fights, no fine print, no arguing. We stand behind it.
Our technicians are background-checked and uniformed. They measure every opening twice, quote manufacturer lines side by side on paper, and treat your home the way they’d treat their own mother’s. A live person answers our phone 24 hours a day, seven days a week. Not a voicemail tree, not a regional call center. When a Marathon homeowner calls at 6 a.m. on a Saturday, a person picks up.
We serve Marathon from our South Florida office, with dispatch and scheduling coordinated out of Miami, and crews on the ground throughout the Middle Keys. You’ll get a straight answer on when we can be there, and we’ll be there when we say.
Our Window Replacement Services in Marathon
Full Frame Replacement
Full frame replacement is the standard fix for Marathon homes with corroded aluminum frames or water-damaged rough openings. We pull the entire old unit down to the studs, inspect the opening for hidden rot, flash the sill pan correctly, and set a new NOA-listed window in marine-grade stainless. On elevated CBS homes along US-1 and in neighborhoods like Sombrero Beach and Key Colony, this is the only way to guarantee the window won’t leak inside the wall cavity. A typical full frame replacement in Marathon runs $1,200-$2,800 per opening, depending on size, material, and impact rating.
Insert Window Replacement
When the existing frame is still square and structurally sound, an insert replacement keeps the original frame and drops a new sash, balance system, and glass package inside it. It’s a less invasive job and costs less, but in Marathon we’re careful about recommending inserts on any frame that’s spent 20 years in salt air. If the aluminum is pitted or the corners are pulling apart, an insert just hides the problem. We’ll tell you the truth either way. Insert replacements in Marathon typically run $700-$1,600 per window.
Storm Window Replacement
Storm window replacement in Marathon isn’t a convenience. It’s the code floor. Every replacement unit in this city has to carry a Miami-Dade NOA or equivalent HVHZ approval. That applies to every window, on every wall, facing either side of the island. Our storm window work includes homes damaged in Hurricane Irma’s near-direct Category 4 hit in 2017, where owners are still finding windows that passed a visual check but fail under current Monroe County standards. Expect $900-$2,200 per opening for a proper impact-rated storm window in Marathon, installed.
Energy-Efficient Upgrade
Energy-efficient windows in Marathon do double duty, because the same laminated impact glass that stops wind-borne debris also blocks a meaningful share of the summer heat load. Low-E coatings and argon fills cut the solar gain that makes AC units run nonstop from May through October. On a single-story ranch on Coco Plum or a two-story CBS home near Vaca Cut, the difference shows up in the electric bill by the first full summer. Energy-efficient replacement windows in Marathon generally run $900-$2,000 per window, and many owners see the fastest payback on west-facing elevations.
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.
Trusted Brands We Service in Marathon
TruePane is an authorized installer for more than a dozen manufacturer lines, including Andersen, Pella, Marvin, Milgard, PGT, and CGI. For Marathon specifically, we quote Marvin, Andersen, and ES Windows most often, because those lines hold the Miami-Dade NOAs that Monroe County requires and the factory hardware spec that survives salt air. We keep common parts and hardware for those lines close at hand so a warranty part doesn’t leave a Marathon homeowner waiting on a container from the mainland. We’ll put manufacturer lines side by side on paper and show you exactly what you’re buying before you sign.
Common Window Replacement Problems We See in Marathon Homes
- Corroded aluminum frames and frozen sashes. Salt air on both the Atlantic and Florida Bay sides attacks aluminum 12 months a year. We routinely replace windows on Marathon homes where the sashes won’t open because the jamb tracks have rotted shut, often within 10 years of an original mainland install.
- Non-compliant pre-Irma jalousie and single-pane windows. Original jalousie windows are charming and useless in a storm. Insurers now flag them on wind mitigations, and Monroe County code won’t let them stay in any repairable, replaceable condition. Replacing them is usually the difference between an insurance renewal and a non-renewal notice.
- Rotted sill pans and clogged weep holes on canal-front homes. When salt spray attacks from below, the window can look fine from the living room while water has been getting behind the stucco for years. We find this constantly on canal-front properties off Sombrero Beach Road and throughout the canals from Vaca Cut to Boot Key.
- Water intrusion and hidden rot behind intact windows. Marathon’s stacked exposure, ocean spray on one side, bay on the other, means drainage failures happen fast. We use flashing tape and neoprene seals at every sill pan, and we don’t skip the weep hole inspection just because the old window was still shedding water.
Pricing for Window Replacement in Marathon, FL
Window replacement in Marathon runs from roughly $700 per window for a modest insert on the low end to $2,800 for a full frame, impact-rated, low-E unit on a large opening. A typical three-bedroom Marathon home with 10-14 windows lands between $12,000 and $30,000 depending on brand, glass package, and condition of the openings. The two biggest price drivers here are the Miami-Dade NOA requirement (impact-rated units cost more by nature) and the marine-grade hardware upgrades salt air demands. The quote we give you is the price you pay. Fixed in writing, no change orders when the job starts. Call (813) 320-9346 for a free estimate, and we’ll put it on paper.
We Also Serve Cities Near Marathon
TruePane’s crews work the entire Middle and Upper Keys. If you’re in Marathon or nearby, we also serve Key Colony Beach, Big Pine Key, Tavernier, and Key Largo, with the same NOA-listed product lines and the same written warranty registration. One phone call covers all of it: (813) 320-9346.
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 - Window Replacement in Marathon
An NOA is a Miami-Dade Notice of Acceptance, a product approval that certifies a window or door has been tested and approved for use in a High-Velocity Hurricane Zone. Marathon sits entirely within Florida’s HVHZ, so Monroe County code requires every new or replacement window to carry an NOA or an equivalent HVHZ approval. A window without one is not legal to install, and insurers can refuse to renew a policy on a home with non-compliant windows. Call (813) 320-9346 if you’re not sure what’s in your walls now, and we’ll check it during the free estimate.
If they’re original jalousie windows, yes, in practical terms you do. Monroe County won’t allow a like-for-like jalousie replacement because the product doesn’t meet any HVHZ impact standard, and most insurers now flag jalousie windows on wind mitigation inspections. You can keep them as ventilated porch glazing in some cases, but as primary window assemblies in occupied rooms, they’re effectively uninsurable in Marathon today. We’ve guided many homeowners through this exact transition.
In Marathon, every elevation of your house is a coastal elevation. The island is roughly a mile wide at its widest, with the Atlantic on one side and Florida Bay on the other, so there’s no leeward side where hardware can dry out or escape the salt. Aluminum frames, stainless hardware, and weatherstripping that would last 20 years in Miami can fail in 8-10 years here. That’s why we spec marine-grade stainless fasteners and neoprene seals on Marathon installs even when the manufacturer’s default would technically pass code. It costs a little more up front and it keeps the window operating a lot longer.
For custom impact windows in Marathon, realistic lead time is 6-10 weeks from order to install, depending on the manufacturer line and the size of the job. An off-the-shelf insert might be 3-4 weeks. The long-lead items aren’t the ones you see, they’re the ones the factory has to build to the Miami-Dade product approval. We order only after you’ve approved the quote and we’ve verified the NOA numbers against your specific openings. You’ll know the delivery date before we place the order, and the price is fixed in writing at that same point.
Sometimes, but only if the wood is in structurally sound condition and the frames can accept a Miami-Dade NOA-listed impact sash. In Marathon’s salt environment, original wood frames are often in worse shape than they look once you strip the paint, especially along canal-front homes where salt spray has wicked into the joints for decades. We’ll assess the frames during the free estimate and give you a straight answer: restore the original frames if they’re worth restoring, full frame replacement if they’re not. For historic window restoration on older Marathon homes, we take the time to do it the way the house deserves. Call (813) 320-9346 and we’ll look at it together.
If you’re ready to replace the windows in your Marathon home, start with a free estimate. A live person answers at (813) 320-9346. We’ll measure every opening, show you manufacturer lines side by side on paper, register both warranty layers in writing, and stand behind the work with the 90-Day Done Right Promise. If the pane is not true, the job is not done.
Written by Dale Kessler, Owner at TruePane Windows & Doors, serving Marathon, FL and the Middle Keys.
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.