Easy Ways to Detect Air Leaks in Your Home

A leaky house is significantly less energy efficient than a properly sealed one. Knowing how to detect air leaks in your house, sealing those leaks and scheduling a home energy assessment when warranted can help you create a comfy living environment and reduce your energy bills.

Detecting Air Leaks from Inside Your Home

Begin your air leak inspection on the inside of your home. Here are four reliable techniques for looking for air leaks in your house:

  • Perform a comprehensive visual inspection, looking for gaps and cracks around windows, doors, electrical outlets and baseboards. Pay extra attention to the corners of rooms, as gaps can commonly be found there.
  • Place your hand near potentially leaky locations on a cold or windy day. If you believe there is a draft, you’ve discovered an air leak.
  • Do a smoke test by lighting an incense stick or smoke pen. Then, slowly move it near the edges of windows, doors and other potential leaky areas. If an air leak is present, the smoke will blow around or get sucked into the gap, revealing the location of a leak. The smoke test is more effective when performed on a windy day.
  • Use an infrared thermometer or thermal camera to detect temperature differences in the different areas of your home. This equipment will help you locate rooms with sizeable temperature variations, which often signify air leaks.

Detecting Air Leaks from Outside Your Home

Inspecting the exterior structure can also expose potential leaks. Here are two methods for detecting air leaks from the outside:

  • Perform a visual examination, paying close attention to corners and places where different materials meet. Search for gaps or cracks that could cause air leaks, as well as worn caulk or weatherstripping and incorrectly sealed vents and exhaust fans.
  • Conduct the garden hose test on a cool day. This is where someone sprays water from a garden hose onto the outside of the house while another person stands inside near a suspected air leak. If there’s a leak, the person inside really should feel cold air or moisture coming through the gap.

Sealing Air Leaks

After identifying serious air leaks, it’s time to address the issue. Here are the best methods for sealing air leaks in your home:

  • Apply caulk to seal small gaps and cracks around windows, doors and other areas where air is escaping. Decide on a quality, long-lasting caulk intended for indoor or outdoor use and the specific materials in question to ensure a durable seal. Follow the manufacturer’s directions for the best application and curing time.
  • Apply weatherstripping to doors and windows to help them close tightly. Various types  of weatherstripping are available, including adhesive-backed foam tape, V-strip and door sweeps. Choose the correct style for your needs and follow the installation instructions.
  • Use expanding foam to fill and seal larger gaps and holes. Expanding foam is available in a can with a spray applicator for simple application in hard-to-reach spots. Wear protective gloves and stick to the manufacturer’s instructions to ensure safe use.
  • Apply insulation to newly sealed walls and attic floors to further reduce heat transfer. Even if you already have some insulation, consider upgrading to a higher R-value or adding more insulation where your current level is inadequate.
  • Install door sweeps along the bottom of exterior doors to restrict drafts. Door sweeps are offered in various materials and styles to fit your needs and aesthetic preferences.

Considering a Comprehensive Home Energy Assessment

A home energy assessment is valuable for identifying concealed air leaks and pinpointing areas of improvement. A professional energy auditor does this inspection, which includes the following:

  • A blower door test entails setting up a temporary door with a sturdy fan over an exterior door opening. The fan pulls air from the house, lowering the interior air pressure and sucking outside air through unsealed openings. This test measures your home’s air tightness and makes thermal camera images more pronounced.
  • Infrared imaging helps the energy auditor detect temperature differences in the walls, floors and ceilings, revealing hidden air leaks and insulation inadequacies.
  • A combustion safety test makes sure your home heating system, water heater and other combustion appliances are operating safely and efficiently, lowering the risk of potentially deadly carbon monoxide buildup.
  • A homeowner interview is when the energy auditor analyzes your energy usage habits, home maintenance history and comfort issues to identify additional energy-saving opportunities.

Schedule a Comprehensive Home Energy Assessment

While performing your own air leak tests is a great launching point, talking everything over with a professional is far more thorough. Service Experts Heating & Air Conditioning can help you improve your home’s air tightness with a detailed home energy assessment and tailored solutions to boost efficiency and comfort.

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