Drafts, condensation, cold floors... If heat is escaping from your home, you need to use more energy to make up for the loss. Did you know that, in Québec, heating accounts for 50% of the energy used in a typical household?

If you are planning major home renovations, consider including work to minimize air leaks and heat loss through your home’s thermal envelope. By keeping heat inside your home in the winter, you’ll lower your energy use and your electricity bill!

Did you know?

About 75% of the heat in a home is lost through its thermal envelope (roofs, walls, ground-bearing floors, windows, etc.). Air leaks and ventilation account for the remaining 25%.

Maximize your renovations

When the exterior siding on your home or your inside walls need to be replaced, it’s often cost-effective to improve the thermal resistance of the walls. Similarly, projects that require access to your home’s foundations or to the inside of walls or roofs are a great opportunity to make improvements that will minimize air leaks and heat loss through your home’s thermal envelope. Some examples of these projects include:

  • Major basement renovations
  • Replacement of exterior siding
  • Major interior renovations
  • Replacement of the shingles on a flat or cathedral roof

If you need to upgrade your home’s thermal insulation, we recommend you take the opportunity to add insulating material and check if your walls, roofs and entire thermal envelope are properly protected against winds and extreme moisture.

Keep in mind that you don’t necessarily need to remove the exterior cladding or interior finishing on your walls to improve your home’s thermal resistance. For example, if you have an accessible attic space, you can add insulating material, a vapor barrier, ventilation and a draft-proofing system, all without any major renovations.

Insulating your thermal envelope: improving thermal resistance

Insulating materials are essential for improving your home’s thermal resistance.

Here are the most common types of insulation

If you do decide to improve the thermal resistance of your home, we recommend aiming for the thermal insulation levels required for new buildings.

Summary of the main regulatory requirements related to thermal resistance

Creating an airtight envelope

Eliminating air leaks reduces heat loss and limits condensation in your home’s envelope.

You may need to carry out work to eliminate air leaks if:

  • Your home is older with many sources of air leaks, and work has never been done to improve its energy efficiency.
  • Condensation is detected in the exterior walls and roofs.
  • The inside of your home has too many cold drafts or is uncomfortably dry in winter.

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