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How to Insulate Exterior Walls From the Inside

Proper insulation of your inside exterior walls is key in keeping your rooms cool in the summer and warm in the winter. Insulating properly can lower your energy usage and help keep you comfortable, regardless of the season. You can also lower your heating and cooling bills and reduce energy waste. Remember, any cracks, gaps, air voids or compression can lower your insulation efficiency by as much as 50 percent, so make sure to spot and correct them when installing your insulation.

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 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.

Inside Exterior Walls

When installing batting on an inside exterior wall, it’s important not to compress it in past the end of the studs. Your insulation should fit snug all around and reach to the top and bottom of the space.

When installing batting around wiring or plumbing, split the batting where you can, running one side behind and one side in front to ensure insulation around all areas. You can also stuff small batts around areas like plumbing, vents, windows and doors.

Once your batting is up, install a continuous sheet of vapour barrier across the wall ensuring complete coverage. Make sure to seal joints and overlap them when possible.

When the insulation and vapour barrier are in place, you can begin installing drywall directly over them.

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Tools You’ll Need

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