Products and ServicesReplacement WindowsReplacement Window Ratings Explained

October 18, 2022

How To Read Replacement Window Ratings
For Your New England Home

There Are Multiple Factors To Consider Before
Replacing Your Windows

When it comes to window replacement, it’s essential to understand how ratings work and what to look for to get the maximum value for your New England Home. Great replacement windows are tested for energy efficiency, expansion measurements, and durability.

Unlike new construction windows, window replacements are made to fit the preexisting window openings. This can lead to several considerations left unchecked when installing replacement windows.

However, replacing windows is an excellent opportunity to upgrade and get more from your window than what came built into your home.

At Solid State Construction, we want you to understand how windows are rated, ensuring you get the best option for you and your family.

Energy Efficiency

The National Fenestration Rating Council (NFRC) tests, certifies and labels windows based primarily on their energy efficiency. The NFRC is a non-profit group that voluntarily rates the energy efficiency of building materials, like windows and doors.

Most Energy Star windows have an NFRC label, ensuring they’ve passed the standards test. Energy Star, however, has its own rating system that considers other elements, including U-Factor and heat gain coefficient.

So, it’s essential to consider all the ratings that make up energy efficiency. These ratings include:

  • U-Factor

You might be asking yourself what the heck U-factor means. Well, U-factor is the rate at which a window transmits non-solar heat flow. Non-solar heat flow is the temperature difference between the outside and inside and impacts your new windows’ efficiency.

Heat flow is measured by how much heat is lost through the window during the winter – and by how much heat is gained during the summer.

This means heat flow-resistant windows are better insulated and have a lower U-factor. Windows with poor insulation are given a higher U-factor. This rating also considers the whole window, including the window frame, glazing, and spacer material.

High-quality double pane windows typically have a U-factor of 0.30 or lower, meaning they’re well insulated. Triple pane windows go even further, acquiring U-factors down to 0.15.

  • Solar Heat Gain Coefficient (SHGC)

SHGC is the fraction of solar radiation allowed through the window and can either be transmitted directly or after its absorption and release into the home.

Lower SHGC levels indicate lower solar heat transmission and more interior shade. This can either be desirable or not based on the local climate and weather. For instance, windows with a low SHGC block more solar heat during the summer, while windows with a low SHGC are great at collecting sun-caused heat gain in the winter.

  • Air Leakage

This rating refers to how much air passes through and around a window. It’s calculated by measuring how many cubic feet of air pass through the window per minute, and its ratings start at 0.1 and go through 0.3, with 0.1 being the best rating possible. A low air leakage rating means it is well insulated, and you’re getting more energy efficiency.

However, it’s not just the window that can determine this rating. The installation also has a lot to do with it, making it essential to find a professional to install your replacement windows.

Additional Window Ratings

When assessing your new windows, a couple of other factors don’t directly relate to energy efficiency. However, they’re still important ratings to look at in order to get long-term use and maximum value out of your replacement windows.

  • Visual Light Transmittance (VT)

This rating measures how well the window lets light in, ranging from 0-1. Low VT ratings mean less natural sunlight gets through the window, while high VT ratings allow more sunlight. Low VT ratings typically accompany tinted windows, which some people prefer.

More than just the type of glass used contributes to this rating. VT also includes other factors like the thickness of the frame and sash and the presence of window grids.

  • Condensation Resistance (CR)

The condensation resistance rating ranges from 0-100, with 100 being the optimum resistance number. Tests that place parts of the window, like the frame and edge-of-glass, in conditions simulating temperature extremes and humidity levels determine this rating.

Let Our New England Company Walk You Through Your
Window Replacement Options

At Solid State Construction, we’ve researched and studied a multitude of windows, ensuring we only sell the best. We not only consider window material, but we factor in the extreme New England weather. Our windows have optimal ratings, ensuring you get the best product for your money.

You will receive the finest replacement windows, installation, and professionalism, and you’ll save lots of money on your monthly energy bills!

Contact us today for a free consultation!