The Window Source of Raleigh offers windows and patio doors that are made to resist harsh temperatures while also offering four-season comfort and energy savings. This saves you money over the course of the product’s lifetime while also keeping your house warm.
Need proof? We surpass the ENERGY STAR® Version 6.0 standards for our climate zone by up to 48% with specific glass packages. The National Fenestration Rating Council (NFRC) accredits windows and offers the four standard ratings listed below:
- U-Factor – A measure of the rate of heat flow through a window. A lower U-Factor indicates a higher performing window that can help reduce heating and cooling costs.
- Solar Heat Gain Coefficient (SHGC) – The amount of solar radiation allowed to pass through a window. The lower the number, the less solar heat gain and UV rays the window permits to enter.
- Visible Light Transmittance (VT) – Ranging from 0 – 1, visible transmittance is a measure of how much light passes through the window. The higher the number, the more light that can pass through.
- Condensation Rating (CR) – CR measures how well a window resists the formation of condensation on the inside surface. CR is expressed as a number between 1 – 100.The higher the number, the better a product is able to resist condensation.
Energy Efficient Glass Ratings
| NFRC Ratings | U-Factor | SHGC | VT | CR |
| Energy Miser 2-IS | .22 | .24 | .38 | 53 |
| Energy Miser 2 | .25 | .24 | .40 | 64 |
| Energy Miser IS | .26 | .26 | .50 | 41 |
| Energy Miser | .30 | .27 | .51 | 52 |
| Clear (No LowE) | .49 | .59 | .61 | 38 |
*Air Infiltration ratings are ≤ 0.3 US (≤ 1.5 Metric) or better for all Window Source Windows.
Energy Miser glass options keep you warmer in the winter and cooler in the summer.
Our Energy Miser Options Are All UV Resistant
Unsafe UV rays can cause more damage to your property than you might think if you don’t take the correct precautions with your windows. For example, UV rays can cause valuable items in your home, like drapes, furniture, carpets, and rugs, to fade.
Our UV-resistant energy saving glass windows are like sunscreen for your house — they block dangerous ultraviolet rays without dramatically reducing the amount of light that enters. Thanks to the Low-E coating options on our windows, which enhance window efficiency and significantly lessen fading and sun damage, your home furnishings will remain colorful for years to come.
To find out how you can save money on energy saving glass windows, talk to one of our consultants about our options!
