PVC Window Jamb Extensions – Traditional Fit, Custom-Cut, Built to Last

Designed for versatility. Ready for paint. Made for Canadian homes.

Why Choose Our Traditional PVC Jamb Extensions?

Built for performance. Designed with precision. Trusted by contractors.

Moisture-Resistant & Durable
Made from premium-grade PVC that resists warping, swelling, and rot — ideal for Canadian climates.
Custom-Cut to Fit
We calculate everything based on your square footage, depth, and window layout to ensure a perfect fit.
Glossy Finish – No Painting Required
High-quality, factory-applied glossy finish that matches PVC windows — no need for painting after installation.
Traditional Trim Compatibility
Maintain the classic look of casings while upgrading to superior moisture-resistant PVC material.
3/4” Standard Thickness
Our jamb extensions are built to a 3/4” standard depth — optimized for most framing and drywall configurations.
Superior to MDF or Imports
No flaking. No swelling. Just clean, professional results that outperform lower-grade trim products.

How to Measure

To get an accurate quote, you'll need your total square footage and jamb depth. Here's how:

1. Measure Window Width & Height

Flat Window: Measure from outer edge to outer edge of the frame for both height and width.

Drywall Return (U-Channel): Hook your tape measure to the inside of the drywall return and measure from inside to inside.

2. Determine Jamb Depth

Measure from the window (or inside edge of drywall return) to the outer edge of the drywall to determine your required jamb depth.

3. Total Your Square Footage

Multiply the height × width of each jamb area and add them up. This helps us cut the correct amount of material with minimal waste.

Contact us if you have an existing jamb that needs an extension.

Window Measurement Diagram showing flat and u-channel
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Installation instructions for window jam extensions, including removing jams from packaging, dry fitting the jam, and applying silicone to the window. The image shows step-by-step directions with photos of the product and window installation process.
Instructions and images showing the process of installing window clips and preparing for window trim. The first image shows clips installed around a window, and the second image shows a finished window ready for trim.
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