How to Insulate an Attic

More than 90 percent of homes in North America lack adequate attic insulation and house insulation. Many homes in Canada lack adequate insulation, costing homeowners more money on energy bills to keep their houses warmer in the winter and cooler in the summer. With proper insulation, you can save money and be more efficient with your energy — and you can start by properly insulating your attic.

If your attic is completely un-insulated, we’ll help you start from scratch. If your attic just needs a top up for maximum efficiency, we’ll help you there as well.

Things to Remember Before Starting

  • Always ensure that your installation is as clear and accessible as possible. You’ll need to be able to move around easily and access all required areas. You’ll also need something sturdy to walk/stand on such as a plank or sheet of plywood.
  • You’ll need some basic tools to help complete your project. Having a hammer, putty knife, caulking gun, tape measure, straight edge, utility knife, a lightweight stapler and a pole or rake (for hard to reach places) will help make this job a lot easier.
  • Lastly, remember that when you open a package of batting, it will expand significantly, so try not to open it outside of your project area.

Uninsulated Attic

For an uninsulated attic, it’s important to install a vapour barrier on the interior side of your roof before filling it with insulation.

When installing your batts, make sure to fit them tightly end-to-end as gaps in the insulation can greatly reduce your R-value. Make sure you don’t block any ventilation areas.

For electrical areas, slide the batts under the wires wherever possible, keeping it away from vents, exhaust fans, chimneys and any other heat-emitting objects and light fixtures. For exact information, consult your local building codes.

Loosefill Insulation

Loose-fill Insulation

Alternatively, you could use loosefill insulation instead of laying down batting. Brands like AttiCat Insulation can be blown in with the proper machinery and when they’re applied this way, the insulation doesn’t settle, ensuring consistent and long-lasting insulation for years to come.

Ensure you use a foam sealant to seal and insulate around any attic windows. You can attach rafter vents - if needed – at the eaves of every joist to ensure optimal ventilation.

Topping Up Your Attic

Topping Up Your Attic

If your attic just needs a top up, you can apply a second layer of batting perpendicular to your current one. Just lay the new batting right on top of your current, between-joist batting.

When insulating, check to make sure that your insulation fits snug to the boards and joists for optimal energy efficiency.

Follow the same rules as if you were doing it from scratch (above) and ensure that all spaces are covered and that there aren’t any gaps.

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Tools You’ll Need

Related Resources