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+-- Thread: Basement insulation (/showthread.php?tid=7172603)
Basement insulation - EricU - 12-20-2015
I had a plumbing leak that ruined some insulation and drywall. I'm thinking about replacing the fiberglass batts with rigid foam. The way that makes the most sense to me is to attach the foam to the walls and then build a 2x wall in front. The only thing with this approach is that it takes up extra space if I go 2x4. I've seen everything from furring strips to a full 2x4 wall proposed. I was thinking about going with a 2x4 on wide edge.
Absent plumbing leaks, the basement is bone dry. The previous owner put up poly foam up against the cinder blocks and there isn't any evidence that there has ever been any water behind it. Which is impressive, since there should have been water behind it just from condensation.
Anyone got comments about this?
Re: Basement insulation - theeviltwinn - 12-20-2015
You get condensation when warm air hits a cooler surface. The foam is a vapor barrier so you won't get condensation unless there is an air leak around it.
Twinn
Re: Basement insulation - EricU - 12-20-2015
you're right, it wouldn't be condensing. However, if there was water intrusion from the outside there would be white deposits on the block.
Re: Basement insulation - vernonator - 12-21-2015
Two Words
Spray Foam - solves all your issues.
Re: Basement insulation - EricU - 12-21-2015
part of my hesitation to go all out is that too much work will result in real estate taxes. A friend cost himself $1000 a year, so I wouldn't manage to net that much in energy savings.
Re: Basement insulation - WaterlooMarc - 12-21-2015
Maybe I'm missing something but how the heck is the county/city going to know what insulation you out in your basement? Surely that doesn't need a permit??
Re: Basement insulation - fredhargis - 12-21-2015
I'm sure Eric will reply, but it's my understanding that PA has a corner on the permit requirements market.
Re: Basement insulation - paulmaine - 12-21-2015
I used 2 inch thick Dow Thermax to insulate my basement. The lower half is single thickness(R13) and the upper half is double thickness(R26). The 4ft x 8 ftx 2 inch foam cost $53 a sheet had to be special ordered in quantities of 22 sheets...I needed 44 sheets for the large basement/garage area. The Thermax has aluminum foil on both sides and Maine building codes do not require a wallboard/ fireboard over it. Attachment was with three pieces running horizontally of 1x3x8 foot boards Titebond 350 caulking under the sheets. The boards were held with Tapcon screws drilled with a DeWalt $99 corded hammer drill...drilled then screwed in The Top layer was fit between the wooden horizontal boards, Tapcons, and caulking. Two inch Aluminized foil Tape Foil tape was used over areas between sheets...Thermax has their own 3 inch version which was much more expensive and looked exactly the same as one sold locally and cheaper.
I had the building inspector OK the job...it was legal and protects me from insurance issues. Several years later I am pleased with thee results and with reducing heating costs.
Re: Basement insulation - WaterlooMarc - 12-21-2015
fredhargis said:
I'm sure Eric will reply, but it's my understanding that PA has a corner on the permit requirements market.
That's nuts. And I thought Alabama was corrupt.
Re: Basement insulation - Cooler - 12-21-2015
I've seen new construction with the foam insulation panels (I assume that they are insulation panels) are applied to the OUTSIDE of the poured basement foundation.
What does that do?