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Frames straightened, resealed and re-capped since 1986
Aluminum window repair is specialist work, and GTS Windows & Doors has been doing it from our Bridgeport base in Kitchener since 1986. We fix bent frames, corroded slider tracks, leaking corner joints and damaged aluminum capping on houses, low-rise apartments and commercial buildings. Our crews are licensed, insured and WSIB covered, so property owners and managers can bring us onto occupied buildings with confidence.
Plenty of aluminum windows in Waterloo Region date from the 1960s to the 1980s, when horizontal sliders were a standard fit in bungalows, backsplits and walk-up apartment blocks. Many of those frames are still structurally sound even though the rollers, gaskets and tracks around them are worn out. Replacing the parts that wear is often a fraction of the cost of a new window, and it is one of the frame services within our wider window repair work.
We also tell you when repair is money poorly spent. Older aluminum frames without a thermal break conduct cold straight through to the room, and no amount of fixing changes that. Homeowners, property managers and general contractors get a straight answer on which path makes sense for the building and the budget, backed by a written quote either way.
Aluminum is light, strong and does not rot, but it has its own failure points. These are the three we are called about most often, and each one is diagnosed differently.
Aluminum is soft compared with steel, so a ladder, a stone thrown by a mower or a snowblower can kink a sill or jamb. Shallow dents in the frame face are cosmetic, but a bent sash rail or track leg stops the window closing and sealing.
We work soft bends back to true with blocks and hand tools. Where the metal has creased or cracked, we replace the sash section or track insert instead, because creased aluminum will not stay straight.
White, powdery pitting forms where water sits in the bottom track, especially on basement windows and on frames splashed by road salt. Blocked drainage slots make it worse, because the track stays wet for days after every rain.
Light oxidation cleans off, and the drainage slots are cleared so the track dries out. Where rollers have worn a groove into the track, we replace the rollers and dress the running surface smooth, or replace the sash where the damage is on the sash side.
Aluminum frames are joined at the corners with screws or crimped clips, and each joint relies on a small amount of factory sealant. After decades of expansion and contraction that sealant lets go, and water tracks through the corner into the wall below.
We clean the joint back to bare metal, tighten or replace the corner fasteners and reseal it with a sealant compatible with aluminum. A water test afterward confirms the corner is dry.
Horizontal aluminum sliders from the 1960s to the 1980s show up across Kitchener, Waterloo and Cambridge, in basements, postwar bungalows and three-storey walk-ups. The original manufacturers are often long gone, which is where experience with parts sourcing matters. We identify the profile by measuring the sash, the roller housing and the track, then source matching parts from window hardware suppliers or adapt the closest equivalent.
Parts we commonly replace on older sliders:
Single-glazed aluminum sashes can sometimes be reglazed with a slim sealed unit where the sash depth allows, which cuts condensation on the glass itself. A sash that has twisted or racked out of square is usually replaced as a unit, because new rollers alone will not make it run straight.
Stiff, noisy or jumping sashes on any make of slider, aluminum or vinyl, are covered in detail on our sliding window repair page. The roller and track work described there applies to aluminum sliders too.
Window capping is the thin aluminum cladding bent to wrap the exterior of wood frames and brickmould. It is formed on site from pre-finished aluminum coil on a sheet metal brake, so each piece is shaped to the exact profile of your trim. Done well, it keeps water and sun off the wood for decades.
Done poorly, it traps water. Capping that was face-nailed in the wrong places, lapped the wrong way or sealed tight along the bottom lets water in at the top and holds it against the wood, which is how rotted brickmould hides behind shiny metal.
What a proper capping job includes:
Capping colours come from the pre-finished coil range, so white, black, brown and the common neutral tones are usually easy to match. Where only one side of a house is being re-capped, we compare samples against the existing metal in daylight before bending anything.
Rotted wood found under old capping is repaired first, using the methods on our wood window frame repair page. Covering soft wood with new metal only hides the problem for a few more years.
Storefronts, office windows and apartment lobbies are usually framed in extruded aluminum systems, from makers such as Kawneer and Alumicor among others. Typical repairs include replacing shrunken or missing glazing gaskets, resetting glass on new setting blocks, resealing perimeter joints and replacing frame sections damaged by vehicles or carts.
Property managers and general contractors can bring us in for a single damaged bay or a deficiency list across a whole building. We plan the work around business hours where possible so the storefront stays open, and we secure any opening that cannot be finished the same day.
For new systems, replacement entrances and larger glazing projects, see our commercial windows and doors services.
Most older residential aluminum windows have no thermal break, meaning the metal runs continuously from outside to inside. On a cold winter morning the interior frame drops well below the dew point of the room air, so it sweats, drips and often frosts over. Repairs restore how the window opens and seals, but they cannot change that physics.
Repair is usually poor value when:
In those cases a modern window is the better investment. Thermally broken aluminum, along with vinyl and fibreglass alternatives, is covered on our aluminum windows page.
Our guide on when to replace windows walks through the wider decision, including energy, comfort and resale. If you are still unsure after reading it, we will price both repair and replacement on the same visit.
These are typical 2026 ranges for Waterloo Region, including parts and labour. Every job gets a written quote once we have seen the window, and a clear photo of the damage helps us price small repairs quickly.
Our installations are backed by a 20-year parts and labour warranty, and each repair quote states exactly what coverage applies to that repair.
| Repair | Typical price (2026) | What moves the price |
|---|---|---|
| Corner joint clean and reseal | $150 to $300 per window | Access height, number of corners, removal of old sealant |
| Straightening a bent frame or sash | $200 to $500 per window | Severity of the bend, whether sash sections need replacing |
| Slider rollers, latch and pile | $200 to $450 per window | Parts availability, sash size, glass weight |
| New aluminum capping | $300 to $700 per window | Window size, trim profile, wood repair underneath |
| Commercial frame and gasket repair | $400 to $1,500 per opening | System type, glass size, lift access, after-hours work |
Often, yes. Soft bends in a sill, track or frame face can usually be worked back with blocks and hand tools, as long as the metal has not creased or cracked. A sharply kinked sash rail or a split corner is normally replaced rather than straightened, because it will not stay true.
Lower indoor humidity helps most: run bathroom and kitchen fans, use the range hood while cooking and keep relative humidity modest in the coldest weeks, often around 30 to 35 percent. Opening blinds and keeping furniture back from the window lets warm room air reach the frame. On a frame with no thermal break these steps reduce condensation but rarely stop it, so replacement is the lasting fix.
Yes. We can re-cap a single window, one side of the house or the whole house without touching the windows themselves. We always check the wood under the old capping first, because new metal over soft wood only hides the damage.
Yes. We repair frames, glazing gaskets, glass stops and perimeter seals on commercial storefront systems, and replace entrances when repair is no longer practical. Full replacements are covered on our storefront and entrance doors page.
Send us a few photos of the frame, track or capping and tell us where the property is. We will confirm whether it is a repair job and book an on-site visit at a time that suits you.
Call or text226-806-0597