Air leakage through can lights, old ducts and crawlspaces not only leads to uncomfortable drafts and odors, it also wastes energy and increases your heating and cooling costs. In California, 30% of energy used in the home is for heating and cooling. Adding insulation and filling gaps around doors and windows with caulk, spray foam and batting are some of the quickest and most cost-effective ways to greatly reduce unseen wasteful air leakage. We are trained contractors and can help you identify areas in your home where air leaks can be sealed in your attic and crawlspace.
Proper ventilation is important, but unwanted air drafts make your home less comfortable. Air sealing reduces leaks and drafts in which treated air can escape from your home, making your air conditioner or furnace work even harder. Sealing creates a controlled barrier between inside and outside air.
We air seal all possible air leakage points where attic air could enter the living space. For example, areas around the plumbing pipes might need to be sealed with rigid foam to keep the assembly free from mold and condensation. Another way we seal the attic is by using expanding spray foam and applying it along every top plate and penetration. Air sealing in the attic is important when it comes to insulating your home because the insulation’s R-value will greatly decrease if air is traveling through it. Air sealing the attic also ensures that your living space air isn’t contaminated by dust, insulation particles, or the odor of rodents in your attic.
Rim Joist Air Sealing
For many homes, the rim joist is one of the major sources of heat loss and air infiltration. A house breathes from the basement up. Typically three quarters of the air infiltration comes from the basement. The air entering or exiting the rim joist area can contain high levels of moisture, increasing the likelihood of mold growth and rot in this area. So if there are mold problems in the basement, this can affect the air quality throughout the house. The rim joist area above the foundation can cause more air leakage into the home than all the windows combined. The project of sealing the rim joist is one of the best things that can be done to make the home more energy efficient. It is important to also seal and insulate the top of the concrete wall where the sill plate sits. It’s the simplest and least expensive basement area to insulate, and will bring the highest return on your investment.
