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A Beginner's Guide to Weatherstripping
Nov 18th, 2019
A Beginner's Guide to Weatherstripping
Do you know your weatherstripping?
by Alec Lower
Drafts and air leaks exist in about every home in America. The edges of windows and doors are the primary enablers for this air outside your home to get inside your home and vice versa. Drafts may not seem like a major issue, but over time they can really drive up your power bill as conditioned air escapes, and they can introduce lots of foreign pollutants from outside into your home. In short, it's something worth fixing, especially since it usually takes about five minutes and 20 dollars to do so.
So how do you actually accomplish this task? With the magic of weatherstripping. Weatherstripping is basically strips of materials that you adhere to doors and windows. These materials, if installed correctly, seal the edges of doors and windows when they're closed, preventing the movement of air any nasty stuff in the air.
Pro Tip: Weatherstripping is commonly associated with wintertime, but it's just as valuable in the summer as it is in the cold months.
How do I know if I need weatherstripping
The first step in identifying where your home needs weatherstripping is to test for air leaks in places that are most vulnerable. There are a handful of do-it-yourself options for this, or you can hire a professional to conduct an energy audit. A professional energy auditor will give you precise answers to where you need weatherstripping, in addition to other useful information.
If you wish to opt for the DIY versions, there are a couple ways to test for insufficient seals.
This requires two people and it needs to be at night. So grab a friend, child, or spouse, promise to buy them a bottle of wine for their help (unless your children are helping—please do not buy wine for your children), and get to work.
The test, which works best for doors, is pretty simple. One person takes a flashlight outside once it's completely dark out. Close the door behind them and have them shine the light all around the door and surrounding areas. If you can see light coming through at any point, that's a point where you have an insufficient seal and should consider adding weatherstripping.
The moisture test
The moisture test only requires one person and can be done at any time of day, but it's helpful if it's done on a cold day. If you're looking to save money this summer, you may want to pick a different test.
The moisture test is also pretty simple. Wet your hand with some room temperature water and then feel your way around the edges of the door or window. The moisture will cause your hand to feel cold if it comes in contact with air from the outside (again, this only works on a cold day). If it feels cool, go ahead and add some weatherstripping.
The dollar bill test
This test is specific to doors and requires the use of a single dollar bill. Open your door and place a dollar bill in between the door jamb and the door itself, then close the door. Grab the bill and try to pull it out. If it slides out easily, time for some weatherstripping.
The smoke test
The final test you can try for a draft in your home is what we'll call the smoke test. This involves lighting a candle or match and holding it behind your door or window. Watch the smoke carefully for changes in how it moves. If incoming air effects the smoke stream, it's a good bet you're losing money and warm/cool air through a draft. Time to do some weatherstripping.
The different varieties of weatherstripping
Who knew weatherstripping could be this complicated? It turns out there are a ton of different kinds of weatherstripping, some of which perform better in certain situations than others. We're going to simplify this down as much as possible.
There are several different varieties to pick from. We did some research for you, and hopefully, this can help you become a weatherstripping expert—or just learn what you need to make an informed decision.
V-Seal is probably the most common type of weatherstripping that is used within the home. Its name comes from the V shape that it takes when you fold it down the middle, which allows it to line the inside edges of window and door frames. It can come with adhesive backing for easy installation, or it can come without one and requires nailing in. If installed correctly, V-Seal can be among the most durable weatherstripping options.
Inexpensive and less durable, felt is sort of the "old news" of the weather stripping community. It's sold in rolls and can be installed stand-alone or with a metal strip for reinforcement. It's useful in doorways where it is affixed or nailed to the door jamb. That way, when the door closes, it compresses the material and blocks out air. It's important to note that felt does not work well in high moisture conditions. Felt is known as the cheapest and one of the easiest options.
The type of weatherstripping best designed to seal out air coming in from underneath the door is what is known as the door sweep. Drafts usually exist at the bottom of doors facing outdoors, which is why this type of weatherstripping exists. You'll often find two options: a metal or plastic strip that you screw into the bottom of the door and a brush, or piece of nylon that extends to the floor (the sweep). If installed correctly, this will cover the entire space beneath the door. Some versions actually slide onto the bottom of the door instead of being nailed into the bottom of the door.
Foam Tape is sort of like of felt except slightly more advanced. While the application is very similar, foam is of higher quality than felt. It usually comes with an adhesive backing for easy installation. Also like felt, it's one of the less durable options and should not be installed in high moisture areas.
This type of weatherstripping may have a variety of different names, but its construction is rubber with adhesive backing. Installation is similar to that of foam tape. Still, the rubber will last longer and is not as vulnerable in moist conditions. It can also provide waterproofing in addition to fighting off air leaks.
One place you might not expect to find an air leak is at your outlets and light switches, but surprisingly, these areas can be just as vulnerable to drafts as your doors and windows. Luckily, covers that seal up these places are cheap and take only a minute to install. It's as simple as removing the plastic covering from the outlet or switch, inserting the foam gasket behind it (make sure you punch out the holes first), and then reinstall the cover. That's it. That's literally it. You should be able to do your entire house for under $20.
Weatherstripping is one of the easiest and most useful do-it-yourself tasks for your home. It's relatively inexpensive, can take only a handful of minutes to install, and will leave you knowing you made your home healthier and more efficient with this quick and easy DIY project.