XPS HD PSI for above concrete slab

ram1500 · 10-14-2012, 01:31 PM

New here but was wonder what you think of placing a 1" XPS foam on floor then 6-10mil poly then 13-15mil laminate on a basement subfloor for 1500 sq ft.

For the 1" XPS stores have 15, but can special order 25-100 PSI.

I would like to avoid adding 1/2 or 3/4 OSB for height reasons.

Been told 15 PSI would be risky of compression but 40-100 PSI would be fine since both foam and laminate will be floating.

I noticed is there are the 4x8 products (anything higher that 15 PSI is special order) and there are also the 2x2 products as well but hard to find. Here are links to each (both are R5 with 60 PSI).

http://insul-armor.com/

http://www.ovrx.com/barricade-plus-subfloor.html

BTW, I live in southern Ontario Canada and house is 10 yrs old, dry concrete with 24RSI 2lb spray foam on wall and headers. Basement will be used as an office and rec area. More of an open concept.

Not sure what the prices are for higher PSI sheets but 2x2 are about $6 each square, while 4x8 PSI is about $18. Still waiting for prices for 60 PSI.

Wondering what you think the XPS PSI should be and is it worth ordering the 2x2 or 4x8 sheets?

Thanks in advance.

gregzoll · 10-14-2012, 01:34 PM

You would be better to lay a sub floor over the XPS. What is the current height. from floor to joists for the main floor?

ram1500 · 10-14-2012, 01:52 PM

Walls and ceilings are already have drywall and primed.

Since this is a basement we have bulkheads around ducts. Under bulk heads is about 79 1/2" high otherwise everywhere else is 90".

As an FYI, bulk head is bout 5ft wide right in the middle of house. Kinda large IMO but there wasn't a choice.

My wife suffers from raynauld's, poor blood circulation in the hands/feet, so it has to be warm.

We will be adding a gas fireplace as well if that helps.

gregzoll · 10-14-2012, 09:51 PM

Your best bet is to use either heat under the flooring, or baseboard rad's, and forgive the xps on the floor. As long as you keep the air moving down there and heat when you are in the space, you will be fine. Personally I hate being in a basement for anything, unless I have to be down there to do something.

It is more of getting the walls insulated, is going to be your best bet, other than trying to put a bunch of work into effort on the floor.

At a little over 6 1/2 feet at the lowest point, and 7 1/2 at the highest, your basement is actually about the same as ours. I have to stoop to get under the duct work above our furnace. due to I am 6'-4".

**Gary in WA** · 10-14-2012, 10:32 PM

The psi depends on the furniture planned... I usually site this at 36# or 5200#ft.2; http://www.cosella-dorken.com/bvf-ca...roducts/fl.php

Here are some other foams/floors: http://www.buildingscience.com/docum...059-slab-happy

http://www.buildingscience.com/docum...ms?full_view=1

Were you looking to heat it?

Gary

10-14-2012, 01:31 PM	#1
ram1500 Newbie Join Date: Oct 2012 Posts: 2	XPS HD PSI for above concrete slab New here but was wonder what you think of placing a 1" XPS foam on floor then 6-10mil poly then 13-15mil laminate on a basement subfloor for 1500 sq ft. For the 1" XPS stores have 15, but can special order 25-100 PSI. I would like to avoid adding 1/2 or 3/4 OSB for height reasons. Been told 15 PSI would be risky of compression but 40-100 PSI would be fine since both foam and laminate will be floating. I noticed is there are the 4x8 products (anything higher that 15 PSI is special order) and there are also the 2x2 products as well but hard to find. Here are links to each (both are R5 with 60 PSI). http://insul-armor.com/ http://www.ovrx.com/barricade-plus-subfloor.html BTW, I live in southern Ontario Canada and house is 10 yrs old, dry concrete with 24RSI 2lb spray foam on wall and headers. Basement will be used as an office and rec area. More of an open concept. Not sure what the prices are for higher PSI sheets but 2x2 are about $6 each square, while 4x8 PSI is about $18. Still waiting for prices for 60 PSI. Wondering what you think the XPS PSI should be and is it worth ordering the 2x2 or 4x8 sheets? Thanks in advance. Last edited by ram1500; 10-14-2012 at 01:38 PM.

10-14-2012, 01:34 PM	#2
gregzoll Average Joe/ex-Navy IC3 Join Date: Dec 2006 Location: Midwest - Central Illinois Posts: 9,652	XPS HD PSI for above concrete slab You would be better to lay a sub floor over the XPS. What is the current height. from floor to joists for the main floor? __________________ *To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.* : Now listen, Cadet. I've got a job for you. See this button? *To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.* : Don't touch it! It's the History Eraser button, you fool! *To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.* : So what'll happen? *To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.* : That's just it. We don't know. Maybe something bad, maybe something good. I guess we'll never know, 'cause you're going to guard it. You won't touch it, will you?

10-14-2012, 01:52 PM	#3
ram1500 Newbie Join Date: Oct 2012 Posts: 2	XPS HD PSI for above concrete slab Walls and ceilings are already have drywall and primed. Since this is a basement we have bulkheads around ducts. Under bulk heads is about 79 1/2" high otherwise everywhere else is 90". As an FYI, bulk head is bout 5ft wide right in the middle of house. Kinda large IMO but there wasn't a choice. My wife suffers from raynauld's, poor blood circulation in the hands/feet, so it has to be warm. We will be adding a gas fireplace as well if that helps.

10-14-2012, 09:51 PM	#4
gregzoll Average Joe/ex-Navy IC3 Join Date: Dec 2006 Location: Midwest - Central Illinois Posts: 9,652	XPS HD PSI for above concrete slab Your best bet is to use either heat under the flooring, or baseboard rad's, and forgive the xps on the floor. As long as you keep the air moving down there and heat when you are in the space, you will be fine. Personally I hate being in a basement for anything, unless I have to be down there to do something. It is more of getting the walls insulated, is going to be your best bet, other than trying to put a bunch of work into effort on the floor. At a little over 6 1/2 feet at the lowest point, and 7 1/2 at the highest, your basement is actually about the same as ours. I have to stoop to get under the duct work above our furnace. due to I am 6'-4". __________________ *To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.* : Now listen, Cadet. I've got a job for you. See this button? *To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.* : Don't touch it! It's the History Eraser button, you fool! *To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.* : So what'll happen? *To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.* : That's just it. We don't know. Maybe something bad, maybe something good. I guess we'll never know, 'cause you're going to guard it. You won't touch it, will you?

10-14-2012, 10:32 PM	#5
Gary in WA Moderator Join Date: Mar 2009 Posts: 8,843	XPS HD PSI for above concrete slab The psi depends on the furniture planned... I usually site this at 36# or 5200#ft.2; http://www.cosella-dorken.com/bvf-ca...roducts/fl.php Here are some other foams/floors: http://www.buildingscience.com/docum...059-slab-happy http://www.buildingscience.com/docum...ms?full_view=1 Were you looking to heat it? Gary __________________ Clothes taking longer to dry? Clean the dryer screen in HOT water if using fabric softener sheets. They leave a residue that impedes air-flow, costing you money. Clean the ducting in the last six months? 17,000 dryer fires annually!

XPS HD PSI for above concrete slab