Air sealing

 Air sealing

weather strippingWeatherization is a cost-effective means, not only to reduce your energy use but, to increase the comfort in your home. According to a recent study by the U.S. Department of Energy, Coloradans can expect to save $2.10 on their energy bills for every $1 they spend on weatherizing their homes.
Air leaks
  • By weatherizing your home, you can reduce air leaks. Weather stripping and caulking are effective for sealing air leaks that occur throughout your home.

Weather stripping

  • Weather stripping comes in a variety of shapes, sizes and materials. Selecting the right weather stripping for the task depends upon the application.
  • V-weather stripping is a long strip folded back on itself along its length and made of metal or vinyl. It forms a springy strip that bridges the gap between the door and the door jam, or a window sash and frame.
  • Durable, long-lasting and easy to install, V-strips come with a pressure sensitive adhesive. Once you cut a strip to the proper length, you may place it on the frame without the use of tools. The flexibility of the tape makes it well suited for irregular-sized cracks.
  • Weather stripping made from rubber, foam or sponge rubber, can be installed against the door and frame to help seal doors and windows


  • Look for cracks, gaps and holes around interior and exterior doors, window frames, walls and vents. Also look for gaps around exterior and interior wall penetrations such as plumbing under the sinks, outdoor faucets, cable television, telephone lines and where natural gas pipes or electrical lines enter the house.
  • Caulk the exterior of your home where siding or trim joins the masonry or siding. This is usually at the corners or walls, and where the siding overlaps the foundation. We recommend the three following caulks, based upon price and performance.
    • From best to good:
      • silicone
      • acrylic latex
      • butyl rubber
    • We recommend silicone caulk for most applications as it sticks to any surface, remains flexible, does not shrink and has a twelve to thirty year life.
    • More caulking materials info.

How to caulk

  • Always remove old caulk before installing new caulk.
  • Make sure the surface is clean and dry.
  • To load a caulking gun, pull the plunger all the way back and insert a tube of caulk into the open sleeve of the caulking gun.
  • Slowly squeeze the caulking gun trigger until the plunger is seated into the back of the caulk.
  • Cut the plastic tip on the tube of caulk at a 45-degree angle about one inch back from the tip. This opening will determine the width of the caulk bead.
  • Next, insert a nail into the end of the caulk and puncture the seal at the base of the tube.
  • Select the area you are caulking and slowly squeeze the trigger.
  • Pull the tip of the caulk gun toward you to spread the caulk evenly and in a straight line.
  • To stop caulking, lift the caulking gun from the surface and pull the plunger back from the caulking gun.

Outlet and switch plate gaskets

  • To seal air leaks that enter through electrical outlets and wall switches, use outlet and switch plate gaskets. They are the same shape as the plastic outlet or switch plate cover but are made of closed-cell foam that is white, flexible and thin. Outlet and switch plate gaskets are effective for stopping air leaks that travel the same path as electrical lines.