Insulating Basement

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Posted by: from Cambridge
7/27/2013 at 11:50:32 AM

I am in the process of finishing my basement. I will be using spray foam insulation and wondered if I had to frame before spraying. I will be spraying 2" of foam.

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Date/Time7/27/2013 at 1:15:46 PM

Yes, you must frame. Run all the wire, plumbing cable, ect first, then you can spray foam.

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Date/Time7/27/2013 at 1:37:13 PM

Do everything before spray foam. Leave the spray foaming to just before drywall.

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Patrick from Fix-R-Upper in Winnipeg
Date/Time7/27/2013 at 2:36:38 PM

Skip framing, just screw the drywall to the spray foam using 3" screws. ;)

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Date/Time7/27/2013 at 3:42:32 PM

Both ways work. Spraying first may be more uniform, however don't overspray areas, otherwise you will have peaks that may need to be shaved to allow for stud installation.

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Date/Time7/27/2013 at 3:59:37 PM


Frame first, run the electric and then spray foam.

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Date/Time7/27/2013 at 5:11:50 PM

You will be better off with framing first. There ia a reason for that as foam expands at least 2" or more and will lock all studs in place and all electrical boxes free of leaking heat.

Make sure that before that your outside walls are well protected against moisture. Reason for that it will be hard after spray to pinpoint potential leak. My house is protected from moisture by water guard that goes as far as foundation. Having that your basement will be warm in winter and cool in summer. Yes it costs but if you want to resell your house make sure you have all documentation. No moisture no mildew or horror stories.

Get at least three estimates and do not be pushed for quick deal. You are the boss and internet is to check all companies in BBB, at least we do it in Canada.

Try to watch video of Bob Villa about spray in insulation, it explains a lot. Today is buyer's market and many companies to get business will give you a good deal. Nobody works for free but excessive price must have justification. Take one or two days to think and if you are uneasy about it it is probably right, do not overide you instincts, they are your guide and trust them.

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Expert Handyman in Ottawa
Date/Time7/28/2013 at 4:41:32 PM

Don't depend on the wall membrane from totally eliminating foundation wall cracks. I've just repaired several homes that both had membranes. In both cases the water found its way behind the membrane and down the foundation wall cracks and into the basement.

My advise is to leave it to a professional or risk severe problems.

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James from JNJ Cabinets in Riverview
Date/Time7/29/2013 at 8:24:48 AM

I find that is better to frame before, and please allow space between the basement and the 2x4 because air circulation is very important. Wood should not touch concrete. And framing first will allow the electrical and plumbing to go very smoothly.

Hope this will help you to have a nice dry basement!!!

James D.

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Date/Time7/29/2013 at 12:38:59 PM

Frame, run wires first and then spray.

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Date/Time7/29/2013 at 8:12:22 PM

It is often easier to frame first, but you should allow for a 1" cap behind the framing to allow for the spray foam behind the studs to provide a thermo break. If you are going with 2" and use the correct foam, you will not have to vapour barrier.


Kingsway Construction Inc


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