Sometimes companies that sell replacement windows exaggerate how much money people might save on their heating and cooling bills when new windows are installed. The truth is the money you could save depends on several factors:
- what material your existing windows are made of
- how well your home is insulated
- the size of your home and how many windows it has
- the shade around your home
- the climate you live in
Of course, when deciding whether new windows will save you money, it’s important to consider the upfront costs. The price per window can range from a few hundred to a few thousand dollars, depending on the materials and features you choose and cost of installation.
The choices you make about materials, style, glazing, and installation could have a big impact on your energy bill. And some features, like how easy they are to take care of, make windows more appealing for other reasons.
Different window frame materials can affect the appearance, durability, and insulation of your window. For example, wood-framed windows provide good insulation, but are heavy and high-maintenance. Vinyl-frame windows insulate well, and don’t need painting.
The style of a window can affect how well your window insulates. Single-hung, double-hung, and sliding windows leak more air than casement, awning, and hopper windows.
Glazing and Glass Technologies
Certain window glazes and glass may provide better insulation, light quality, and condensation resistance. For example, windows with low-emissivity (low-e) coatings often are more energy efficient than windows without.
Cleaning and Maintenance
Some materials and features, like tilt-in sashes, make windows easier to care for.
If your windows are not installed according to the manufacturer’s instructions, you might not get the savings or comfort you expect.
Check the Label
Look for the National Fenestration Rating Council’s window label when you shop. It can help you compare how well a window blocks cold, heat, and outside air; allows light in; and blocks condensation.
These ratings measure how well a window blocks cold, heat and outside air:
- U-factor: Rates how well a window prevents heat from escaping through a window. In cold climate, look for a low u-factor rating. Range: 0.2 — 1.
- Solar Heat Gain Coefficient (SHGC): Rates how much heat from the sun is allowed in. In warm climates, look for a low SHGC rating. Range: 0 — 1
- Air Leakage: The closer this number is to 0.1, the more outside air leaks in. Range: 0.1 — 0.3
Visible Transmittance ratings measure how well a window allows light in:
- The closer this number is to 1 the more light the window lets in. Range: 0 — 1
Condensation Resistance ratings measure how well a window resists condensation:
- The closer this number is to 100, the better the window is at resisting condensation. Range: 1 — 100