Find Out What a Window Frame Is And Why It's Important

Knowing the window frame’s makeup and materials can help you make a better choice.
Related To:
Pros and Cons of Aluminum Windows

Aluminum Windows: Pros and Cons

Although aluminum windows provide more color options than vinyl and are just as durable, aluminum windows are notorious for their energy inefficiency and are susceptible to corrosive effects of the salt air, so they are not ideal for coastal areas.

A window frame is the window’s structural support. Window frames are divided into a head side (the top), sill side (bottom) and jambs (sides).

While you’ve probably thought of improving the quality of your glass to increase thermal insulation, you can do the same for your frames, saving money and making your home more comfortable.

There are five basic frame materials:

·         Metal (including aluminum)

Window & Aluminum Cap 04:19

This piece looks at insulating and then capping window frames,

·         Composite

·         Fiberglass

·         Vinyl

·         Wood

Each material has advantages and disadvantages and some frame materials provide more thermal resistance than others.

Metal Frames

Metal frames are very light, strong and virtually maintenance free – and they’re also one of the most affordable options for window frames. But they conduct heat rapidly, which makes them a poor insulator. To reduce thermal load, make sure your metal frames contain a thermal strip between the frame and sash.

Composite Frames

Composite frames are made from a mix of wood particles and plastic, which makes them stronger and more durable than wood alone. They’re sometimes considered the best replacement window option because they offer the strength of wood with the same low maintenance and energy efficiency as vinyl. The downside is that they can be expensive.

Fiberglass Frames

Fiberglass frames offer the same stability as wood and, because they can be filled with insulation, they have better thermal performance than wood or uninsulated vinyl. Fiberglass is a more common choice for commercial buildings than homes, probably because they’re more expensive than other window frames, and they have fewer sizes and features than other frame materials.

Vinyl Frames

Vinyl frames, composed of UV-resistant PVC, have good moisture resistance, don’t require painting and are virtually maintenance free. These affordable frames can be insulated, like fiberglass frames, to improve energy efficiency. They are also one of the most affordable options. However, vinyl responds to temperature shifts, causing windows to expand and contract, which can potentially lead to seal deterioration and drafts. If you choose vinyl, plan to have them re-caulked and re-sealed regularly during their lifetime.

Wood Frames

This classic material is a favorite of many homeowners for its warm appearance, ability to match any architectural style and its overall energy efficiency. However, wood window frames are high maintenance, requiring regular scraping and painting, and prone to wood rot and insect infestation. They’re also on the higher end, cost-wise.

Before you choose a window frame, consider cost, energy efficiency and the pros and cons of each material type. Experts agree, purchase the highest quality window you can afford, even if you install them in stages. It will pay off in the long run with improved function, durability and energy efficiency.

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