The importance of weatherstripping doors

Why you should add weatherstripping to your entry doors and how to DIY

Key tips to remember

  • Weatherstripping a door creates an improved air seal
  • The better a home is sealed, the more efficient its HVAC unit will be
  • More-efficient HVAC units demand less energy
  • Reduced energy usage lowers energy bills
  • You can replace weatherstripping yourself
Maintenance and Repairs

What is the best way to weatherstrip a door? How do you weatherstrip an interior door? What do I put at the bottom of a door to seal it? If you’ve asked yourself these questions or others related to various types of door weatherstripping, we’ve got some helpful answers to share. Whether you’re looking into exterior door weatherstripping types for metal exterior doors, wooden interior doors, French door weatherstripping or something else, this article will get you on the right track to deciding what you need and if you want to DIY.

What does it mean to weatherstrip your door?

How do you make a door airtight? The answer is weatherstripping. Top-, side- or bottom-door weatherstripping encompasses a variety of metal, wooden, plastic, vinyl and silicone materials used to create a door seal strip designed to create a solid air seal around the frame of your doors. This seal helps to ensure cool or warm air stays inside and colder or hotter air stays outside so your home’s temperature is more efficiently and effectively regulated year-round. Better-sealed doors keep your family more comfortable and your energy bills at reasonable levels. When effectively applied, weatherstripping can eliminate the extra chill from drafts and air leaks. The process consists of several main components:

  • A typical door sweep includes a metal frame or flange with vinyl, felt, plastic or sponge bristles that sweep along the bottom of a door on the interior side against the threshold.
  • A V-channel, also known as a V-strip or tension seal, is usually metal and used at the top and along the sides of a door to create an invisible seal that lasts.
  • Felt seals are usually synthetic or made of wool. They’re used to improve seals around doors and near hinges. While felt seals are inexpensive, they’re not very durable.
  • Foam tape weatherstripping is often made of vinyl, rubber or PVC. It’s cheap and easy to use to improve seals around doors due to its adhesive side; although, it too breaks down easily.
  • Vinyl or silicone bulb flanges have a lower profile, take up less space, and are therefore less conspicuous; although, they aren’t quite as good at filling gaps as foam tape.

Weatherstripping for different types of doors

Whether you’re dealing with interior doors, exterior doors, metal doors, French doors or garage doors, weatherstripping is important. The best weatherstripping for old doors is no different from the best weatherstripping for new doors. However, most older doors weren’t made with integral weatherstripping, so it’ll be up to you to add it. This process requires a bit more work than for a newer door, or you can hire a pro. 

Whatever sort of door you’re dealing with, what’s important is that you achieve a good seal on all four sides, one that maintains an impenetrable wall between the air inside and the air outside your home. A great first step is to check with the manufacturer of your door or the store where your door was purchased because there may be weatherstripping pieces designed specifically for your model.

How do you weatherstrip a door?

First, gather tools like a pry bar, coping saw, hacksaw, hammer and nails, screwdriver, stepladder, router and utility knife. You might also need a door sweep, foam flange or vinyl bulb for the doorsill. A weatherstripping kit that includes various weatherstripping materials might include these parts and others for use with different doors, depending on the size and make of the door and your particular needs. 

The basic steps for prepping your door frame for weatherstripping include cleaning it thoroughly and letting it dry, then measuring, cutting and applying foam or another type of weatherstripping along the frame’s sides and top. Finish by installing a sweep above the threshold at the bottom of the door so that it sweeps across the floor when opening and shutting, making direct contact but not constricting movement.

How-to steps for DIYers

  1. Hinges: You might not have even considered hinge screws, but if you have gaps, your door could be misaligned. Start by making sure the screws in each hinge are tightly in place. If any spin and refuse to bite, you may have to glue some wood plugs into the holes, wait for them to dry, and then try drilling in the screws again. This could prove to be a huge relief and solve your whole problem before you even start weatherstripping.
  2. Door jambs: With the door closed, measure the top section of the frame from left to right. Transfer this measurement to your foam weatherstripping with a straight line, cut it with scissors, and then cut the wood flange with whichever fine-toothed saw you have available. Position the strip so that the foam seal touches the door. Hammer 1.5-inch nails part of the way in about 2 inches apart, then measure the door frame’s sides. Cut side pieces and install as before, making any necessary adjustments. Test your fit by opening and closing the door several times, going for an airtight fit on all three sides, and hammer in all the nails.
  3. Door sweep: Measure your door’s inside width and transfer that measurement to the sweep you plan to install. Cut the flap with a knife or scissors, and then cut the flange with the fine-toothed saw. With the new flange in place and the flap touching the threshold, use a marker to note screw points and drill your pilot holes. Push down the sweep and proceed to install the screws with your drill. If you’re still using a section of old weatherstripping over the threshold that is worn down or torn up, go ahead and replace it now after cleaning out any accumulated grime amid the grooves.
  4. Corners: To finish the job properly by sealing the corners, cut sections of 1/8-inch felt into 1.75-inch pads. Tack them into the bottom of each side of the door frame. Try the door a few times, check for air drafts or escaping sunlight, and make adjustments as needed. If you still have big gaps, you might need a larger door sweep. If your door sweep is older, you may need to replace it anyway. If you still have gaps between the felt and the sweep at the corners, double up on the felt for a finished seal.

Weatherstripping doors, as with many potential DIY projects, can vary from a quick fix to a major operation. Depending on what sort of door you have and what shape the door and the frame are in, you could be looking at a long day of work or a couple of hours or less of relatively quick fixes.

While we’re on the topic of home improvements, you might be wondering whether a home warranty covers garage doors or how to prepare your home for fall. Spend some time browsing throughout our blog, and you’re sure to find more insights. You may also have some interest in our compilation of home maintenance schedules by region.  You can sign up for our newsletter and follow us on Facebook for even more home-improvement tips.


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