How to inspect doors for air and water leaks

Air and water leaks in the home or office can sometimes be frustrating.

Air leakage alone can contribute to significant loss of coolness where air conditioners are turned on during hot days. It also accounts for 15-25 per cent of heat loss in buildings and houses throughout those cooler months.

Did you know that 40 per cent of energy is used at home for heating and cooling? This is mostly due to air and water leaks of houses.

Where do air leaks typically occur?
  • Poorly sealed or unsealed doors
  • Common doors and walls between attached dwelling units
  • Fireplace wall
  • Dropped ceiling
  • Porch roof
  • Shaft for piping
  • Ducts
  • Exterior wall penetrations
  • Garage or living space walls
  • Rim joists, foundation, floor
  • Chimney shaft
  • Air barrier and thermal barrier alignment
  • Recessed lights
  • Attic access
  • Whole-house fan
Where do water leaks typically occur?
  • Poorly sealed or unsealed doors
  • Water supply line
  • Faucet, shower and tub
  • Toilet

With the number of possibilities mentioned above, door issues are one of the common factors. It is important that you inspect your doors to find out if they are a problem.

You have two choices to have your doors inspected for leaks;

  1. You can get a professional inspection and let them do the job. They will provide the materials and all you have to do is pay them.
  2. Or you can do it on your own – which will obviously be much cheaper!

If you have decided to do it on your own, here is how to inspect doors for air and water leaks.

When checking for air and water leaks, start with a thorough inspection using your eyes.

It seems pretty straightforward, but it really is the first step! Look for areas where old caulking has failed, which may reveal a gap between the door frame and your home’s siding.

Examine the threshold under your door. Check if there’s daylight or wind passing through. That signifies an opening that needs to be sealed.

Close all the doors that you want to test.

This is the best and only way to find air leaks.

If you have a laser thermometer, make use of it.

Shoot the laser thermometer beam to the doors that you want to test. This is to get the ambient temperature in the room. To double check, use your laser thermometer outside. This is comparing the temperature inside and outside your house. If you’ve noticed that a certain area inside your house has the same reading of temperature as outside, that’s when you know your door has a leak.

Conduct a smoke test.

After you have closed all the windows and doors in your house, turn off any combustion appliances such as water heaters, ovens, stoves, fireplaces and clothes dryers. Next, turn on the kitchen and bathroom exhaust vents. This will create negative pressure in your house that draws outside air into your house through any crack or opening.

You can check the air leaks by holding a lit incense stick close to the edges of your doors. Look for the change in the smoke from the lit incense stick. If the smoke remains the same, there are no air leaks. You will know there is an air leak when the smoke will waiver and be drawn inwards by the outside air.

When you have checked the doors for air and water leaks, if you find any you can now plan on sealing them!


For more top tips, or to chat to an industry professional, give us a call today.