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These Windows are Energy Efficient


In the South Bay Peninsula and Santa Cruz area, where summer heat glaring through the windows can quickly get uncomfortable, window efficiency has a noticeable effect on your comfort.

Modern Features for Efficiency

Casement, sliding, and single- or double-hung models can all achieve high levels of energy efficiency, so when you're looking for new windows, the material used is more important than the window type.

Because the durability and insulating ability of double-paned windows is so much greater than that of single-paned designs, the latter are usually not recommended. If you live in a cooler part of the Peninsula region and want a little extra window insulation for winter, look for argon-filled models.

Low-emissivity (low-e) glass improves efficiency even further. This glass is coated with a film that reduces heat transfer from the sun's rays in summer and keeps your warmth indoors in winter.

Vinyl and wood-clad vinyl frames provide good insulation at a relatively low cost. Wood is also a good choice, but you'll want to air seal the windows carefully to prevent air leaks. Avoid aluminum, which conducts heat easily and can heat up your home in summer.

Efficiency Ratings to Know

Thanks to two window efficiency ratings, you can easily judge the combined effect of the features included in any given window.

  • U-factor— This rating tells you the insulating capability of a window, with a lower number indicating more effective insulation. Because this isn't a critical factor in our north-central climate, a U-factor of 0.4 or less is sufficient.
  • Solar heat gain coefficient (SHGC)— This rating tells you how much of the sun's heat the window lets in, so it's an important number in our warm climate. The lower the number, the less solar radiation the window lets pass. If you often use your A/C, look for a SHGC of 0.4 or less.

Visit our website at Valley Heating, Cooling, Electrical for in-depth information on most HVAC topics, or just give us a call at (408) 868-5500 wherever you are in the South Bay Peninsula and Santa Cruz area.

Our goal is to help educate our customers in the South Bay Peninsula and Santa Cruz areas of California about energy and home comfort issues (specific to HVAC systems).

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