What To Look For When Shopping For an Energy Efficient Entry Door
Chelsea O'Donnell
Many people don’t give much thought to their front door, which is surprising considering that it both sets the tone for a home and is a huge contributor to its overall comfort level.
If you’re in the market for a new entry door, there are a lot of factors to take into consideration beyond just color and style. I’m a huge fan of energy efficiency and all too often, I see homeowners losing massive amounts of hot and cold air through ill-fitting old doors with little insulation. Luckily, consumers have some great resources in their corner which can make choosing a new door a real breeze.
Energy performance is often measured by ENERGY STAR®, the symbol created by the Environmental Protection Agency to measure energy efficiency here in the United States. Another label you may see is from the National Fenestration Rating Council (NFRC), which independently tests and certifies products to give consumers more transparency around efficiency. Both of these rating systems rely on several vital performance contributors that you’ll want to pay attention to. Let’s take a closer look.
U-Factor measures how well the product keeps heat from escaping a room, which is vital to our cold winters. It’s important to look for a low number here, which identifies a high performing product. Ratings generally range from 0.20-1.20.
Solar Heat Gain Coefficient or (SHGC) measures the opposite. This rating helps a homeowner to know how well a product can resist heat gain, which is crucial in the summer. Again, the lower the number, the better - with 0-1 being the range for this measurement.
Air Leakage is exactly what it sounds like and if you’ve ever stood next to a door with worn weatherstripping, you’ll know how important it is. Look for a product with a low air leakage rating, generally expressed in units of cubic feet per minute per square foot of the frame area (cfm/ft2). This measure is also highly dependent on the installation of the product, so having a knowledgeable installer is critical.
Sunlight is another important factor which is measured through Visible Transmittance or VT. VT is a fraction of the visible spectrum of sunlight that is transmitted through the glazing of a door and weighted by the sensitivity of the human eye. This is measured in nanometers on a scale of 0 to 1. The lower the number, the less the light is transmitted.
Finally, Light-to-Solar Gain (LSG) is the ratio of SHGC to VT and helps homeowners understand how light is transmitted relative to heat gain. The higher the number, the more light that is transmitted without adding heat. This number isn’t always provided but can be useful depending on the positioning of your door and its exposure to the sun.
Don’t forget, exterior doors should look great, but their key function is to provide a barrier against the elements. When you’re shopping for one, keep these factors in the forefront of your mind and you’ll be taking all the steps necessary to maintain your family’s comfort for years to come.
Bob O’Donnell is the owner of O’Donnell Bros. Inc., a Bristol-based home improvement company established in 1975. Email your questions for Bob to info@odonnellbros.com with the subject line “Ask the Pro.” All questions may be considered for publication. To contact Bob for your remodeling needs, call O’Donnell Bros. Inc. at (860) 589-5155 or visit http://www.odonnellbros.com. Advice is for guidance only.