How to Make Your Doors More Energy Efficient

Thinking about some Do-It-Yourself (DIY) home improvement projects for your Texas home, but you’re not really sure about what to do or where to start? You’ve come to the right place! Welcome to the DIY Energy Efficiency Tips series from First Choice Power. We’ll show you how to improve the energy efficiency of your home, including hints that make the jobs easier.

Making Your Doors More Energy Efficient

How to Make Your Doors More Energy Efficient | The Light Lab

The problem with exterior doors is that they are not only the biggest holes in the side of your home, but they also see a lot of action over the years. Factory applied weather stripping wears out, dirt accumulates crevices along seals, and seasonal swelling and shrinking can effect how well it closes. Plus, depending on where the door is facing, there’s also weathering from sunshine, rain, and even ice. Doors take a real pounding and often after several years, they don’t keep the outside outside as well as they used to. They let moist outside air in, causing your heating bill to increase in the winter and your cooling bill to increase in the summer.

How bad is it, really? Consider that a standard 36” x 80” residential exterior door with a 1/32” gap all the way around is equal to a 7 1/4” hole in your wall. That’s about the diameter of one gallon ice cream bucket!

Making drafty doors seal better is actually not very expensive and usually only requires some caulk, weather stripping, and perhaps some foam backer. While newer doors don’t take long to repair, older doors — especially wooden ones — need a little more care and preparation. Either way, making your home’s entry doors seal better will improve your entire home’s energy efficiency.

Begin By Finding Closure

Dirt and debris are typically the main culprits behind drafty doors because they gets into seals and gaskets and prevent them from sealing. Over time, trapped dirt will tear holes into the gaskets or seals, requiring them to be replaced. The first thing you should do for weatherizing your doors is to clean dirt and debris from tracks and jambs. Also, look for areas where mud or dirt cake onto weather stripping and clean that as well.

Next, look for places on the door where the weatherstripping is torn, squished, stretched, or missing. Steel or fiberglass doors usually have factory installed weather stripping applied on both sides (jambs) and across the top (lintel) so that when the door closes, it creates a good seal against the outside air. Self-adhesive foam weather stripping is inexpensive and easy to apply — but it’s not always the right kind. You’ll want the right stuff for the right job. Newer EnergyStar rated entry doors use weather stripping that magnetically sticks to the metal door.

Now, check to see if you can close a piece of paper in the door and pull it out. Since doors tend to not close with uniform firmness in their frames, you’ll need to do this test all around the door. You’ll likely find that some parts of the door close more tightly than others. If the paper is difficult to pull out, then you’ve probably got a good seal. If the paper slides out easily, there’s a gap big enough for a draft. Close up these gaps by adding weatherstripping to the doorstop and repeat the paper test.

At the Threshold

How to Make Your Doors More Energy Efficient | The Light Lab

Every time the door is opened, the vinyl threshold sweeps on the bottom of the door and brushes against the threshold plate plus any dirt, leaves, and little bits of rock that have accumulated there. Depending on your local environment, they can wear very quickly. If your door’s threshold sweep is torn and battered, you can put on a new sweep with an inexpensive vinyl kit that is easy to install.

Many factory pre-hung doors come with an adjustable threshold that you can raise or lower with a screwdriver. Over time, this threshold raise and lower and wander out of alignment with the door’s bottom. It takes just a little time to tweak it back into place. Again, you can test how well the door seals against the threshold by doing the paper test, but be extra careful here. If the threshold is too high and the paper tears when you pull it, the threshold sweep will wear faster. If it’s too loose, it could let in outside air and possibly rain water.

Mind the Gap

After taking care of weather stripping, go outside and check around the door frame for gaps or holes. Fill any that you find with caulk.

TIP — Do not use expanding foam for sealing gaps in door frames. This foam can expand to push the door frame inwards and prevent the door from closing.

What Kind of Doors Are Energy Efficient?

The energy efficiency of an exterior door depends on its material, such as wood, fiberglass, or steel. While wood does a better job at not conducting heat, both fiberglass and steel are strong enough to be hollow frames that are filled with foam insulation. So, r-values for doors run from R-2 for 1 3/4” wood all the way up to R-11 for a 2” thick steel door with a foam core. However, once you begin putting windows into a door, that R-value starts falling because glass has a very poor R-value. Consequently, EnergySaver doors are evaluated according to glass and air leakage performance, among other things.

Adding a storm door in front of an older door does help improve energy efficiency. Many new storm doors now come with foam cores and this boosts their R-values and improves air sealing. Unfortunately, EnergyStar does not currently qualify storm doors (or storm windows).

What About Sliding Glass Patio Doors?

How to Make Your Doors More Energy Efficient | The Light Lab

Because they are practically nothing but glass, sliding glass patio doors depend almost entirely on their weather stripping to seal out the weather. Next to maintaining that valuable weather stripping, using drapes or curtains will do the most good towards adding a layer of insulation and shade against cold or hot temperatures.

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Vernon Trollinger is a writer with a background in home improvement, electronics, fiction writing, and archaeology. He now writes about green energy technology, home energy efficiency, the natural gas industry, and the electrical grid.