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Circle-D Posted: Apr 16, 2007 07:36 PM	Required thickness What is the general opinion as to the required installtion thickness of closed cell foams? I read "The Polyurethane Foam Book" by David South, and he states 1 1/2" in ample in the walls. Other reports I've read state a minimum of 2" to be a vapor/moisture barrier. Yet others swear by more. I realize in some areas of the country there are building codes that must be adhered to, even if it is overkill. In my northern climate and rural area, building codes haven't caught up to us yet. I want to make sure I am doing the right thing and not making a bad name for the SPF industry and at the same time giving a good value to the client. If you don't spray enough you can almost always beat the other guy on price.........but as they say " the bitterness of poor quality lingers long after the sweetness of low price is gone". I'm interested in doing a quality job, for my own reputation, that of the industry and in the best interest of the clients. What are the feelings of the more experienced foamers out there?
Gerry Wagoner Posted: Apr 17, 2007 09:58 AM	Hi CD. I can give some guidelines that hopefully will be useful. In order to acheive a vapor-barrier, the perm rating of the foamed wall must be less than a 1. This is generally not possible at 1.5". All foam insulations are required by the FTC to publish an Insulation Fact Sheet regarding their product. Ask for one on the foams in question and you will be able to determine what thickness will yield a less-than-1 perm. In our projects, we sell 2.5" of closed cell in a 2x4 wall. In a 2x6 wall we often install 3" of closed cell or 4" of 1.2 Platinum. Two inches is fine in the garage, and 1.5" in basement walls (below grade). Have fun, olger
Circle-D Posted: Apr 17, 2007 10:12 AM	Thank you, Olger. I will look that info up in my spec. sheets. Skip

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Comments

Circle-D

Posted: Apr 16, 2007 07:36 PM

Required thickness

What is the general opinion as to the required installtion thickness of closed cell foams? I read "The Polyurethane Foam Book" by David South, and he states 1 1/2" in ample in the walls. Other reports I've read state a minimum of 2" to be a vapor/moisture barrier. Yet others swear by more.
I realize in some areas of the country there are building codes that must be adhered to, even if it is overkill. In my northern climate and rural area, building codes haven't caught up to us yet.
I want to make sure I am doing the right thing and not making a bad name for the SPF industry and at the same time giving a good value to the client.
If you don't spray enough you can almost always beat the other guy on price.........but as they say " the bitterness of poor quality lingers long after the sweetness of low price is gone".
I'm interested in doing a quality job, for my own reputation, that of the industry and in the best interest of the clients.
What are the feelings of the more experienced foamers out there?

Gerry Wagoner

Posted: Apr 17, 2007 09:58 AM

Hi CD. I can give some guidelines that hopefully will be useful.

In order to acheive a vapor-barrier, the perm rating of the foamed wall must be less than a 1. This is generally not possible at 1.5". All foam insulations are required by the FTC to publish an Insulation Fact Sheet regarding their product. Ask for one on the foams in question and you will be able to determine what thickness will yield a less-than-1 perm.

In our projects, we sell 2.5" of closed cell in a 2x4 wall. In a 2x6 wall we often install 3" of closed cell or 4" of 1.2 Platinum. Two inches is fine in the garage, and 1.5" in basement walls (below grade).

Have fun,

olger

Circle-D

Posted: Apr 17, 2007 10:12 AM

Thank you, Olger. I will look that info up in my spec. sheets. Skip

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