Foam Insulation Questions - Please help

kuj0317 · 01-27-2012, 02:04 PM

Hello All

I love this forum, but I hate this topic. I have done a good amount of research, and get so many conflicting answers.

I live in Westchester NY (southen NY).

I have a finished basement which was ruined by hurricaine Irene. It was old, witch warped wood paneling, so not a huge loss.

I pulled off the wood paneling, and found that it had 2x3 framing done at inconsistent intervals. I tore that down.

Now I have an exposed, but painted cinderblock wall. My idea is to glue 2 inch XPS foam (Pactiv 2 inch foam, R10) to the inside wall.

http://www.lowes.com/pd_304090-210-3...1#BVRRWidgetID

$32/sheet is expensive, so I want to do this right.

The cinderblock is painted, so I do not need to apply anything like drylock, right?

Can I can adhere the foam directly to the cinderblock? If so, using what adhesive?

To run electrical, can I route channels in the foam?

I do not wish to redo the electrical. All runs drop down from the ceiling. They are in metal sheathed casings. Do I need a nail plate?

In terms of moisture, is this a good setup?

I apologize if this post is redundant, but as I said before, I have gotten so much conflicting advice.

Thank you.

-K

Beepster · 01-27-2012, 02:16 PM

After tons of research at this site and all the attached "Building Sciences" links provided by GBR, I went with 1" XPS glued to the block walls and will 2x4 frame over that. By going only 1", I will need to monitor the humidity in the summer and keep it below 50%. There is an adhesive amongst the million different tubes at the big box stores specifically for foambaord (ML300??). Do not cut channels in the foamboard, you would defeating what you are doing. 2x frame over and run your elect as it was. Rewire with romex if necessary.

B

Windows on Wash · 01-27-2012, 03:31 PM

+1 to Beepster's comments as well.

2" would be fine as well and still keep you at about 0.6 perm rating.

Make sure the ribbon boards are sealed up properly as well.

**Gary in WA** · 01-27-2012, 08:31 PM

Yep. I'd check on that brand foamboard, though. I believe it is faced with a poly, which you don't want below grade: http://www.buildingscience.com/docum...lation-systems An alternative is ESP, but make up the R-value for your location.

Gary