Floors, walls, ceilings, and doors and windows all combine to make up the "energy envelope" of your home. Caulking seals the small cracks and holes in the envelope; weatherstripping seals around doors and windows to help make your home airtight.
Weatherstripping and caulking is probably the least expensive, simplest, most effective way to cut down on wasted energy in the winter and summer. Improperly sealed homes can squander 10 to 15 percent of the homeowner's heating dollars and reduce the effectiveness of air-conditioning in the summer.
While some new doors now come with factory-applied weatherstripping, such designs are a recent innovation. Millions of doors across the country have little or no weatherstripping. Since most doors have a space - sometimes as much as a quarter inch or more - between the bottom of the door and the floor, large amounts of air can flow in and out of the house. For a typical 36-inch entry door, a quarter-inch small crack can leak as much air as a nine-square-inch hole in the wall.
Weatherstripping comes in many forms, and can be made up of a combination of materials such as wood, rubber, vinyl, metal and foam. Some types work well on both doors and windows, while others are more limited. These are the major designs you'll find for use around the house:
Adhesive-Backed Foam or Tape
This material, made from rubber, foam or sponge rubber, can be installed in the same manner as V-strip to help seal doors and windows. Hardware stores sell it in various widths and thicknesses, and the tape is self-adhesive and easy to install. Simply cut the tape to the length you need with scissors, peel away the backing from the tape and stick it in place.
The size and flexibility of tape make it well suited for blocking irregular-sized cracks. It wears out quickly, however, and needs to be replaced often - probably every one to two years.
Felt, either plain or reinforced with a flexible metal strip, is sold in rolls that must be cut to length and stapled or tacked into place. Plain felt should be fitted in a door jamb so that the door presses against it; reinforced felt can be used to seal around both doors and windows. Felt traditionally lasts one to two years before it needs to be replaced.
A variation on felt is pile, a carpet-like material that can be glued or tacked in place. It comes in narrow, furry strips.
This is the best, most complex, most expensive weatherstripping. Think of two V-strips that are placed on the door and the door frame. When the door closes, the two pieces interlock to make a tight seal. Interlocking pieces are placed completely around the perimeter of the door - on the top, both sides and the bottom.
Installing interlocking weatherstripping can be tricky, since both the door and the frame must be notched with a router. That's why this type of installation is usually done by professionals.
Tubular Rubber and Vinyl Gaskets
Small tubes of sponge rubber or vinyl can also be used to weatherstrip around doors and windows. When the door presses against the gasket, it forms a tight seal. By pressing against these gaskets, the door forms a seal. The tubes come with a flange that can be tacked or stapled to hold them in place. Usually they last five years or more.
The floor underneath a closed exterior door usually has a raised seal called a threshold. Many thresholds have weatherstripping built in. One style includes a tubular gasket seal built into the threshold that presses against the bottom of the door to keep out drafts.
Other threshold weatherstripping is mounted on the door itself. One style called a door sweep features a flexible flap that seals against the threshold.
A long strip folded back on itself along its length, this type of weatherstripping can be made of either metal or vinyl. It forms a springy strip that bridges the gap between a door and the door jam - or a window sash and the window frame - to prevent the movement of air. Durable, long-lasting and easy to install, V-strips come with a pressure sensitive adhesive; once you have cut a strip to the proper length, you can stick it in place on the frame without the use of tools.
Wall Sockets / Outlets / Switches
There's a final place in your home we need to mention when it comes to weatherstripping - electric wall sockets and switches. Although they aren't in the same category as doors and windows, the holes in our walls for electrical outlets and switches do allow cold air into a house in the wintertime and leak cool, air-conditioning air in the summer. It's a good idea to purchase simple-to-install, pre-cut foam gaskets that fit behind the switch or plug plate to effectively reduce leaks.
Insulation is another important component in sealing your home's envelope. Click here to learn more.