As homes age, the problems associated with air infiltration may increase as caulking products dry out and weatherstripping wears. One of the easiest chores a homeowner can do is sealing air leaks that contribute to high energy bills year-round.
Air infiltration is a two-way street, coming in or out, and both lead to thermal losses. These situations promote air leakage:
Incoming Air
- On windy days, air can enter your home through the smallest cracks around window frames, exterior doors and any other places where your home has cracks in its exterior walls and doors.
- If your home has leaky ductwork that runs through the attic, the positive air pressure in the ducts when the HVAC system runs can pull unconditioned air into your home through any cracks in the attic or roof. Many homes in our region have attached garages, and if your ducts leak, the pressure can pull toxic fumes into your home from the garage. Sealing air leaks in the garage with caulk and weatherstripping will help mitigate this danger.
- When you close off a room to save energy, and block the supply register and leave the return register open, the closed room’s air pressure will drop. To compensate, air will enter from any cracks in the exterior wall, windows or exterior door frame.
Outgoing Air
Air leaving your home is a less common phenomenon, but it can, especially in the winter. Heat always travels to cold, and in the winter, you can lose heat to the outdoors through your home’s envelope and attic.
Fixing Air Leaks With Caulk
Caulk is an easy, inexpensive product that can seal leaks around stationary objects, like window frames, in structural cracks and around pipes, wires or cables. Several types of caulk are available, each suited to different applications.
- Silicon. This caulk is a long-lasting solution for use around places that will get hot, since it’s relatively impervious to heat and it’s flexible as temperatures change. It bonds well with metals, and uncured silicon caulk must be cleaned up with mineral spirits.
- Latex. This is the least expensive caulk available, and it’s water-based, making clean up easy. It’s available as interior or exterior caulk, and it’s useful for sealing around cracks in window frames and exterior door frames. Outdoors, the caulk can be painted, which also helps it resist UV light from the sun, which can degrade it.
- Expanding. Expanding foam is good for air sealing air leaks around larger cracks.
Most caulk comes in tubes that require a caulking gun, an inexpensive tool available at hardware and home centers. When applying it, hold the gun at a 45 degree angle and insert the tip as deeply into the crack as possible. Squeeze the lever as evenly as possible. Have a damp cloth or solvent available to wipe away any residue.
Fixing Air Leaks With Weatherstripping
Weatherstripping is the product of choice for sealing air leaks around objects that move. It’s available with or without adhesive. These are the most commonly used types:
- Foam. This weatherstripping is easy to cut and apply. When the door closes, the foam compresses, eliminating any possibility of drafts.
- Felt. This is another easy to apply weatherstripping, but as you select it, choose wool felt because it’s more durable.
- V-strip. Either metal or plastic, a V-strip is one of the more durable weatherstripping products. When the door or window is closed, the V closes and makes a tight seal. It can be mounted with finishing nails or stuck in place if it has an adhesive backing.
- Silicon, rubber or vinyl. These can be mounted to the door jambs or window sashes. They are stapled or nailed in place, for a durable and tight seal.
- Door sweeps. A door sweep is a strip of metal that can be attached to the bottom of a door. It has soft bristles at the bottom that won’t wear flooring, but will stop drafts at the bottom of the door.
For more information about sealing air leaks in the Baltimore metro area, contact Griffith Energy Services, Inc. today.
Written by Kevin Spain
