New Energy Star Specifications

The U.S. Environmental Protection Agency released its final draft of the Version 6.0 specification for Energy Star windows and doors. Among the changes in the latest proposal is a revised implementation date, with the new standards now set to take effect January 1, 2015, instead of early 2014, as previously planned.   The draft maintains a 0.27 U-factor maximum for windows in the Northern climate zone. This is an increase from the previous U-factor maximum of 0.30.  The latest version of the criteria also includes air leakage labeling requirements, revised to allow existing certification labels in lieu of including an air leakage value on the National Fenestration Rating Council temporary label. The majority of windows manufacturers do not currently list or label their window’s air infiltration rating due to poor to average performance in this area. The air infiltration maximum will remain at less than or equal to 0.30 cubic feet of air per minute for double hung windows. When shopping for replacement windows we encourage consumers to inquire about a windows’ U-factor and air infiltration rating in order to understand the quality of the product they are buying.

The OKNA 800 window already exceeds the January 1, 2015 mandate by offering a 0.26 U-factor for double pane glass. In addition to an already excellent U-factor, the OKNA 800 has an air infiltration rating of 0.01, which is approximately 3000% better than the industry minimum. The industry average for air infiltration is 0.20 which is why many companies to not post their rating. Meanwhile, air leakage accounts for 25-40% of the energy used for heating and cooling in a typical home, according to test results from AAMA.

How to read a nfrc window label

Vinyl windows are the most frequently installed replacement window in the U.S.  And fortunately for consumers all vinyl replacement windows come with a rating label that helps a person determine how efficient a window can be.

How to Read/Interpret Vinyl Windows Ratings

Become familiar with the components of the window label and write down the ratings appropriate for your area before shopping. Here’s what to look for:

  1. U-factor. This is how much heat/cold transfers through the entire window frame (glass and vinyl). The lower the U-factor, the better the window resists heat/cold transfer. Vinyl windows with gaps in the framework (i.e. mechanical frames) will have a higher U-factor than a fusion welded window.
  2. SHGC–Solar Heat Gain Coefficient. The SHGC is the ability of the window to block the sun’s heat. The more heat a window blocks, the lower vinyl windows ratings will be for heat gain.
  3. Visible Light Transmission. The more light that is allowed to flow through the glass, the higher this rating will be.
  4. Low-E glass. This glass has a transparent metallic coating that reflects heat back into the home in winter and reflects heat away from it in the summer.
  5. ENERGY STAR rating. An independent organization tests and rates the energy efficiency of windows. ENERGY STAR windows qualify for a tax rebate through 2013.

What is low emissivity glass and how does it benefit you?

Markey Home Remodeling - Low Emissivity (Low E) Glass

Markey Home Remodeling - Low Emissivity (Low E) GlassLow emissivity (Low-E) actually low thermal emissivity is a quality of a surface that radiates, or emits, low levels of radiant thermal (heat) energy. All materials absorb, reflect and emit radiant energy.  The benefit of Low- E glass – actually low thermal emissivity – is a quality of a surface that radiates, or emits, low levels of radiant thermal (heat) energy. What does that mean for the consumer? Or better yet, how does that benefit a homeowner and what can a person expect when putting in replacement windows with low-e glass?  For one, if your home (front or back) faces a southern exposure chances are that during the summer months your home will heats up due to the sun’s rays directly penetrating through your existing clear glass windows.  The benefit of replacing your clear glass windows with energy-star rated low-e glass windows is that they will reduce the need for a home owner to constantly run their A/C on hot sunny days. This happens due to the coating of Low-E on the glass. These coatings reflect radiant infrared energy, thus tending to keep radiant heat on the same side of the glass from which it originated, while letting visible light pass. Another additional benefit is that low-e glass protects you furniture, hard-wood floors, carpet and curtains from fading due to the sun.