Basement Insulation..PLEASE HELP

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Miche

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I'm about to insulate my bare concrete walls. I've done research on how to do this and found a million ways. This is how I wanted to do it.

1inch foam board insulation clued to concrete wall. Then build 2x4 wall against foam and fill with roxul insulation. Then drywall and paint

Is this ok?
I've read that with this method I do not need poly vapour barrier between roxul and drywall because the foam board acts as vapour barrier plus latex paint on drywall will also act as vapours barrier.

Is this a good method to insulate my walls. I don't want to make a mistake and have to redo in the future

PLEASE HELP!!
 
Vapor barrier doesn't cost that much. If latex paint was considered a vapor barrier then I imagine house wrap would not be needed.
Are you going to tape the seams on the foam boards?
How will you know if/when you have a basement foundation leak leading to mold behind the wall?
 
Yes that will work, up here that is the standard with out the foam and then add the vapour barrier.
The type of concrete forms we use up here always leaves the inside surface less than perfect so applying foam board and getting it to seal all gaps is next to impossible. So when done if you are not sure you have a good seal you could just cover it with poly for a guarantee. The other problem is if you ever do get a leak, finding it is near impossible too.

A couple other thoughts while I am here. there should be a fire stop at the top of that wall between any cavity and the floor system.
If you have full height concrete wall where the stop is needed make the top plate of the wall out of 2x6 or 2x8 or what ever the distance is from the inside of your wall and the top plate above the concrete that gives you that 1" space too. And a moisture break between wood and concrete any where they might touch.

That fire stop trick also makes it easy to square up the rooms down stairs as you are just following the lead from upstairs.
 
Ok so it's ok not to use the poly if I'm putting foam board on the concrete? And yes I will be taping all the seams in the foam board. I will also be insulating the floor joists
 
Ok so it's ok not to use the poly if I'm putting foam board on the concrete? And yes I will be taping all the seams in the foam board. I will also be insulating the floor joists

Floor joists in a basement is whole different discussion.
 
I did my basement several years ago and followed a youtube video that originated with This Old House. I put 2" foil backed rigid foam insulation against the block wall and then, using tapcons, screwed through a 1"X4" board placed horizontal against the wall. I put one of these 1X4"s every 2 feet. After that, I screwed 1"X4" boards vertically over these horizontal boards, on 16" centers. After that sheetrock. On the floor I used Dricon flooring as a subfloor. It has been 4 years now without any issues.
 

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