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ENERGY STAR
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Breadcrumb
  1. Home
  2. Energy Savings At Home
  3. Seal and Insulate With ENERGY STAR
  4. A DIY Guide To Sealing and Insulating With ENERGY STAR
  5. Locating Air Leaks

Heat & Cool Efficiently

Seal and Insulate

  • Why Seal and Insulate?
  • Methodology for Estimated Energy Savings
  • Program Requirements
  • Choosing the Appropriate Insulation Type
  • Identify the Problems You Want to Fix
  • Determine the Effort Required
  • Assess the Level of Opportunity
  • Attic Air Sealing Project
  • Attic Insulation Project
  • Basement & Crawlspace Air Sealing and Insulating Project
  • Sealing Behind Window & Door Trim Project
  • Applying Plastic Over Windows Project
  • A DIY Guide to Sealing and Insulating with ENERGY STAR
    • Getting Started
    • Locating Air Leaks
    • Sealing Air Leaks: Attic
    • Sealing Air Leaks: Basement
    • Adding Attic Insulation
    • About Attic Ventilation
    • Glossary
  • Rule Your Attic! For Comfort and Savings

Expert Home Improvements

Locating Air Leaks

More than any other time of year, you notice your home's air leaks in the winter. Most people call these air leaks "drafts." You may feel these drafts around windows and doors and think these leaks are your major source of wasted energy. In most homes, however, the most significant air leaks are hidden in the attic and basement. These are the leaks that significantly raise your energy bill and make your house uncomfortable.

But locating leaks can be difficult because they are often hidden under your insulation. In cold weather, warm air rises in your house, just like it does in a chimney. This air, which you have paid to heat, is just wasted as it rises up into your attic and sucks cold air in all around your home — around windows, doors, and through holes into the basement.

Common Household Air Leaks

  • Behind Kneewalls
  • Attic Hatch
  • Wiring Holes
  • Plumbing Vent
  • Open Soffit (the box that hides the recessed lights)
  • Recessed Light
  • Furnace Flue or Duct Chaseway (the hollow box or wall feature that hides ducts)
  • Basement Rim Joists (where the foundation meets the wood framing)
  • Windows and Doors

Locating Basement Air Leaks

A common area of air leakage in the basement is along the top of the basement wall where cement or block comes in contact with the wood frame. These leaks can easily be fixed in portions of the basement that are unfinished. Since the top of the wall is above ground, outside air can be drawn in through cracks and gaps where the house framing sits on top of the foundation. This perimeter framing is called the rim (or band) joist. In the basement, the above floor joists end at the rim joist creating multiple cavities along the length of the wall, and many opportunities for leakage.

Continue to Sealing Air Leaks: Attic

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