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How to: Air Sealing for Energy Efficiency

July 13 2015, 08:35 AM

How to: Air Sealing for Energy Efficiency

Air sealing is one of the most important upgrades you can make in your home. It’s also inexpensive and easy to do. With a little effort and minimal cost you can do these air sealing upgrades yourself.  Following these steps to air seal your home can help lower your heating bills by up to 20% and help make your home more comfortable and less drafty this winter.

Where to check

Air sealing can be done easily and quickly in several areas of the home including electrical entrances, windows, doors, light fixtures, light switches, plugs, baseboards, doors and hatches, and floor joists. Older homes (built before 1970) in particular have many penetrations to the outside, causing drafts and allowing heat to escape.

An easy way to find leaks is to hold a feather or incense stick next to any of the areas listed above. If it’s moving, that means you’ve got an air leak. If proper air sealing has not been done that means cold air can get in and warm air can get out.

Fix the leaks

You’ll need either caulk or spray foam to seal your leaks. Generally, any gaps and spaces less than 3-4cm can be sealed with caulking and anything larger should be sealed with spray foam.

To fix the leak with caulking, just run your caulk gun around the edge of the window to seal it off completely. Caulk is really difficult to get off once dried, so it’s best to apply painters tape to both sides of the joint to help keep things clean. You should also wear gloves when applying caulk to seal your leaks.

Light switches and outlets are another source of air leakage.  It’s easy to see and feel the cool air coming in. Inexpensive foam insulators can fix these air leaks easily and quickly. All you need to do is unscrew the switch covers then fit in a foam gasket. Screw the covers back on and you’re all set. If you have outlets on external walls, plug covers can also help keep air from coming in through the outlet itself.


Don’t forget the door

Make it a seasonal chore to check your doors.  You should replace weather-stripping if it is dried out, cracked, ripped, compressed or missing, or if it bends at all. Check all the sides of the door and the door sweep underneath.

Make sure the door closes snugly and that there are no gaps along the sides, top of the door or in the space between the threshold and the door bottom.  Your weather-stripping ensures a tight seal where the frames meet. It is also inexpensive to replace and helps keep warm air in during the winter, and vice versa in the summer. 


Don’t forget that as you make your home more airtight, you will also need to ensure your home is properly ventilated and humidity levels are controlled to prevent moisture and mold problems. Do you have a ventilation system? A heat recovery ventilator will be essential to keeping your home properly ventilated if you’re successful in air sealing.

Bigger projects

If you know your home is in need of major air sealing and you want to ensure a thorough and professional job in locating and sealing, your best option may be to call in a professional. Look under Insulation Contractors in your local yellow pages to find a contractor who will work with you to have all sources of leaks and drafts in your home identified and thoroughly sealed.

NB Power is also offering the Total Home Energy Savings Program for homeowners to help with insulation and air sealing.


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