Quick question about 4x8 foam

eurovw89 · 02-06-2012, 08:17 PM

Hi everyone....I have searched this forum and everywhere else, but cant seem to find a solution....hope someone can help.

I live in a townhouse with poured concrete walls in basement, (middle unit) in Maryland, and getting ready to hang drywall. The front of my basement is 6' under ground and I'm stuck on what to do for insulation. I had to frame the walls 6" from the concrete wall due to plumbing so I'm wondering if I could use 2'' foam insulation on top of the concrete wall between the studs, just use batts, or should use both?

Hope this makes sense.....

Any help is greatly appreciated

Jeff

joecaption · 02-06-2012, 08:21 PM

There has to be 2 or 3 hundred post on this one subject. Please take the time to look at some of the older post.

eurovw89 · 02-06-2012, 11:00 PM

Quote:

Originally Posted by joecaption

There has to be 2 or 3 hundred post on this one subject. Please take the time to look at some of the older post.

This is what I am doing (couldnt find the website earlier)
http://www.buildingscience.com/docum...ion-assemblies
The problem i have is that I had to start my framing 5'' from the concrete wall....after I install the XPS I will have a 3'' gap between XPS and framing....what can I use to make up that void?

Beepster · 02-07-2012, 09:45 AM

What do you mean "due to plumbing"? What do you have there that you think the wall has to be ahead of? Pics?

B

concretemasonry · 02-07-2012, 10:01 AM

Euro -

Just use the 2" XPS foam on the concrete and don't bother with the insulation in the stud wall wherever you decide to build the stud wall. In your climate, the soil is not that cold and you really would not be able to justify the cost of over-insulating, especially with batts that can hold moisture and feed mold if there is moisture.

For the stud wall, make sure you use pressure treated plates on the concrete floor and appropriate nails/connectors.

I assume this level is or will be conditioned space, so make sure you have air returns just off the floor. They can do wonders for uniformity and can benefit is you have AC. I have a single zone home with an open stairway and always can maintain a maximum temperature difference of 2F whether it is 100F or -20F outside.

Dick

Beepster · 02-07-2012, 12:01 PM

You have this and the hijacked thread going at the same time on the same subject. Try and keep it to one thread.

Put the XPS against the foundation and leave small gaps by the plumbing to spray in behind them with 'Great Stuff'. Put the 2x4 framing right up against the XPS. No gaps. Gaps are bad.

Where do you live?

B

eurovw89 · 02-07-2012, 07:47 PM

Quote:

Originally Posted by Beepster

You have this and the hijacked thread going at the same time on the same subject. Try and keep it to one thread.

Put the XPS against the foundation and leave small gaps by the plumbing to spray in behind them with 'Great Stuff'. Put the 2x4 framing right up against the XPS. No gaps. Gaps are bad.

Where do you live?

B

I live in Maryland. The framing is already up. could I put the XPS up and just use insulation for 2x6 walls in between studs for fill up the gaps?

02-06-2012, 08:17 PM	#1
eurovw89 Newbie Join Date: Feb 2011 Location: Maryland Posts: 13	Quick question about 4x8 foam Hi everyone....I have searched this forum and everywhere else, but cant seem to find a solution....hope someone can help. I live in a townhouse with poured concrete walls in basement, (middle unit) in Maryland, and getting ready to hang drywall. The front of my basement is 6' under ground and I'm stuck on what to do for insulation. I had to frame the walls 6" from the concrete wall due to plumbing so I'm wondering if I could use 2'' foam insulation on top of the concrete wall between the studs, just use batts, or should use both? Hope this makes sense..... Any help is greatly appreciated Jeff

02-06-2012, 08:21 PM	#2
joecaption Member Join Date: Nov 2011 Location: Hartfield VA Posts: 18,822	Quick question about 4x8 foam There has to be 2 or 3 hundred post on this one subject. Please take the time to look at some of the older post.

02-07-2012, 09:45 AM	#4
Beepster Member Join Date: Oct 2009 Location: Minneapolis, MN Posts: 399	Quick question about 4x8 foam What do you mean "due to plumbing"? What do you have there that you think the wall has to be ahead of? Pics? B

02-07-2012, 10:01 AM	#5
concretemasonry Member Join Date: Oct 2006 Location: Minneapolis/St. Paul, Minnesota - Latitude 45.057 Longitude -93.074 Posts: 3,357	Quick question about 4x8 foam Euro - Just use the 2" XPS foam on the concrete and don't bother with the insulation in the stud wall wherever you decide to build the stud wall. In your climate, the soil is not that cold and you really would not be able to justify the cost of over-insulating, especially with batts that can hold moisture and feed mold if there is moisture. For the stud wall, make sure you use pressure treated plates on the concrete floor and appropriate nails/connectors. I assume this level is or will be conditioned space, so make sure you have air returns just off the floor. They can do wonders for uniformity and can benefit is you have AC. I have a single zone home with an open stairway and always can maintain a maximum temperature difference of 2F whether it is 100F or -20F outside. Dick Last edited by concretemasonry; 02-07-2012 at 10:06 AM.

02-07-2012, 12:01 PM	#6
Beepster Member Join Date: Oct 2009 Location: Minneapolis, MN Posts: 399	Quick question about 4x8 foam You have this and the hijacked thread going at the same time on the same subject. Try and keep it to one thread. Put the XPS against the foundation and leave small gaps by the plumbing to spray in behind them with 'Great Stuff'. Put the 2x4 framing right up against the XPS. No gaps. Gaps are bad. Where do you live? B

Quick question about 4x8 foam