Basement Framing And Insulation

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Posted by: from Newmarket
12/31/2018 at 8:32:51 AM

Existing insulation and drywall are in the basement walls, probably original build. Some parts only half the wall.

Can I build a 2x4 wall in front of that and insulate with roxul.

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Date/Time12/31/2018 at 7:20:57 PM

Yes you can absolutely do that as long as the existing insulation is not wet and as long as you don't mind wasting the extra space with adding another wall in front of the existing one

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Date/Time12/31/2018 at 7:29:47 PM

Absolutely. That is standard procedure for renovating a basement. Make sure to fix any cracks or future problem areas prior to covering it up

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Steve from OMC Contracting in Kitchener
Date/Time12/31/2018 at 9:40:00 PM

2x4 framing was used before when the building code required R12 the code changed in 2016 and now R20 is required that means 2x6 framing is required.

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Date/Time12/31/2018 at 11:27:46 PM

Under the previous Code basement walls were only required to be insulated to 2' below grade and R-12 was more than enough. With the recent introduction of Energy Codes that has changed and insulation value has to be determined as an assembly including the studs - typically R-20 now for the full height.

One choice is to install 2" of rigid insulation to the lower half of the wall that is presently uninsulated, then 2 x 4 framing plus R-12 or 14 batt insulation should satisfy the requirements. ensuring vapor barrier is on the warm side of the insulation.

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Date/Time1/2/2019 at 4:10:26 PM


I would tear out everything that is there and start over. It is important to see the block wall underneath to ensure there are no air or water leaks, before covering everything up forever.

This will ensure that all of the work and finishes to come afterwards will not be at risk.

Then install the 2x6" stud wall and R20 insulation and 6 mil vapour barrier. Be sure to use the blue rot-resistant bottom plates from Lowes, wrapped in vapor barrier.


Andrew Parker

Par-Tek Design Build Ltd.

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Kirk from KLK CONTRACTING in Perth
Date/Time2/5/2019 at 8:44:40 PM

Tear out the existing insulation and drywall to avoid mold and mildew problems.

A little work now will save you a lot down the road.

Hope this helps.


KLK Contracting

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