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Retrofit window install slotted into existing frame

Installation Method

Retrofit Window Installation

Insert-style replacement. Existing frame and exterior brick mould stay put. New triple-pane unit drops in — typically in under an hour per opening.

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Why Retrofit

Fastest, cleanest path to new windows.

If your existing frames are sound, retrofit installation gives you the full energy and noise benefits of a new triple-pane unit without disturbing the brick mould, exterior trim or interior casing. Less labour, less mess, lower cost.

  • 30–60 minutes per opening
  • No exterior or interior finishing required
  • Same triple-pane Cardinal IG glass packages
  • Lower cost per opening than brick-to-brick
  • Lifetime product warranty
Retrofit window detail

Our Process

Four steps, typically under an hour per window

1

Measure inside the frame

We measure the daylight opening — width, height and squareness of the existing frame stays in place.

2

Remove old sash & glass

Operable sash, stops and old IG unit come out. The original frame remains.

3

Insulate the gap

Low-expansion foam between the new unit and the existing frame, plus backer rod where needed.

4

Set & seal

New unit is mechanically fastened, then sealed inside and out with paint-grade silicone.

Most full-home retrofit projects finish in a single day. No exterior repainting, no interior re-casing, no drywall touch-ups.

FAQ

Frequently Asked Questions

Retrofit (also called insert replacement) installs a new window directly into the existing frame. The interior trim, exterior brick mould and original frame stay in place — only the operable unit and the old glass come out.
When the existing frame is sound, the brick mould is in good shape and the opening size isn't changing. It's faster, less disruptive, and typically 25–40% cheaper than brick-to-brick.
Slightly — typically ½" to 1" around the perimeter, since the new unit sits inside the existing frame. We measure the daylight opening during the assessment so you see the exact glass size before signing.
30–60 minutes per opening. Most full-home retrofit projects finish in one day.
Energy performance is comparable when the existing frame is sound, because the new triple-pane unit is identical. Brick-to-brick wins when the rough opening itself needs re-insulating.

Flexible Financing Options Available

0% promotional plans and low monthly payments through licensed Ontario lenders. Pre-qualify in minutes.

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Lifetime Product Warranty

Frames, sashes, hardware and our workmanship — covered for as long as you own the home.

Why homeowners trust us

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Free Quote

Free estimate on retrofit installation

We'll inspect every frame on-site and confirm whether retrofit, brick-to-brick or hybrid is the right method for each opening.

  • Detailed project assessment
  • Written itemized quotation
  • Product and installation recommendations
  • Financing options available

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