How To Locate Air Leaks Inside

How To Locate Air Leaks Inside

Air Leaks

First, find obvious drafts and make a list so you can plug later with caulk or weather stripping. (The potential energy savings from reducing drafts in a home may range from 5% to 30% per year).

Other places to check for potential airflow:

  • Electrical outlets
  • Switch plates
  • Window frames
  • Baseboards
  • Weather stripping around doors
  • Fireplace dampers
  • Attic hatches
  • Wall- or window-mounted air conditioners.

Tip 1: When checking windows and doors for air leaks, see if you can rattle them, which could indicate potential air flow.

Tip 2: If you can see daylight around a door or window frame, then the door or window leaks.

Next, you can conduct a basic pressurization test:

  1. First, close all exterior doors, windows, and fireplace flues.
  2. Turn off all combustion appliances such as gas burning furnaces and water heaters.
  3. Then turn on all exhaust fans (generally located in the kitchen and bathrooms) or use a large window fan to suck the air out of the rooms.

This test increases infiltration through cracks and leaks, making them easier to detect. You can use incense sticks or your damp hand to locate these leaks. If you use incense sticks, moving air will cause the smoke to waver, and if you use your damp hand, any drafts will feel cool to your hand.

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