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Author	Comments
Matt Lehr Posted: Mar 02, 2008 07:52 AM	off gases Its been 3 days since since I had poly. spray foam installed and the smell is still strong. I have the windows open and fans running. Will the smell go away? Is there something wrong?
mason Posted: Mar 02, 2008 09:07 AM	Take some core samples of the foam and look for signs of poor mix, (elongated cells, splits, cracks, voids, seperation, etc.) Odor should be gone from the foam within a few hours to a few days.
Matt Lehr Posted: Mar 02, 2008 09:24 AM	Core was taken in an area that showed some movement to the foam when pressed with hand. It revealed a large air pocket and what looked like stringy cells inside the void. My fear is that this movement is in many places. Other places have no movement. What does this mean. Do these pockets have an effect on the performance of the oc spf? If so what should be done?
Matt Lehr Posted: Mar 02, 2008 11:33 AM	I took some more core samples using a coffee can and discovered that there is a 1" space between the sheething and the foam that I can reach into in all directions. It appears that when the spf was applied it expanded trapping air between it and the sheathing.This cannot be good. Can it be?
mason Posted: Mar 12, 2008 02:02 PM	Matt, No the foam should not have significant voids or separation. You may want to perform some thermal imaging tests to determine the extent of the problem.
Tim O'Keefe Posted: Mar 12, 2008 10:09 PM	Stringy cells and a strong smell would indicate to me an off ratio installation where you have an excess of the "B" component which will stay smelly and has the tendency to continue to shrink and pull away as it will never actually become the foam it was intended. Tim Granite State Spray Foam Co.
mason Posted: Mar 14, 2008 08:36 PM	Yep, what he said
Matt Lehr Posted: Mar 14, 2008 08:51 PM	OK. The smell has almost gone. The company did come back and core out all the air pockets and refoamed. What should I look for as far as failing foam if the mix is bad? and how soon? Thanks
mason Posted: Mar 15, 2008 08:50 AM	A-rich foam will be dark in color, higher density and more brittle. B rich foam will be lower density, lighter in color, softer and with cell deformation. B rich foam can shrink, have poor compressive strength, cause odors and not have sufficient R value, A rich foam can delaminate and easier, R value may be affected depending on the degree of off ratio blend. A poor mix can cause problems also even if the foam is on ration. Poor mix would result in foam that has discoloration, cell deformation, odor, inconsistent compressive strength. The fix to any of these problems is to identify the defective foam, remove it and re-foam. NOTE: Open cell foamers who switch to closed cell foam typically make the same mistake, spraying the lifts of foam too thick. Closed cell foam should be sprayed in thickness between 1-2 inches, then let the foam set for about 10 minutes and build up additonal thickness. If you spray too thick a pass, exothermic heat can build up inside the foam, causing lower density, , separation, and even charring of the foam in extreme cases. Talk to your supplier about the best way to spray their foam.

Author

Comments

Matt Lehr

Posted: Mar 02, 2008 07:52 AM

off gases

Its been 3 days since since I had poly. spray foam installed and the smell is still strong. I have the windows open and fans running. Will the smell go away? Is there something wrong?

mason

Posted: Mar 02, 2008 09:07 AM

Take some core samples of the foam and look for signs of poor mix, (elongated cells, splits, cracks, voids, seperation, etc.) Odor should be gone from the foam within a few hours to a few days.

Matt Lehr

Posted: Mar 02, 2008 09:24 AM

Core was taken in an area that showed some movement to the foam when pressed with hand. It revealed a large air pocket and what looked like stringy cells inside the void. My fear is that this movement is in many places. Other places have no movement. What does this mean. Do these pockets have an effect on the performance of the oc spf? If so what should be done?

Matt Lehr

Posted: Mar 02, 2008 11:33 AM

I took some more core samples using a coffee can and discovered that there is a 1" space between the sheething and the foam that I can reach into in all directions. It appears that when the spf was applied it expanded trapping air between it and the sheathing.This cannot be good. Can it be?

mason

Posted: Mar 12, 2008 02:02 PM

Matt,

No the foam should not have significant voids or separation. You may want to perform some thermal imaging tests to determine the extent of the problem.

Tim O'Keefe

Posted: Mar 12, 2008 10:09 PM

Stringy cells and a strong smell would indicate to me an off ratio installation where you have an excess of the "B" component which will stay smelly and has the tendency to continue to shrink and pull away as it will never actually become the foam it was intended.

Tim
Granite State Spray Foam Co.

mason

Posted: Mar 14, 2008 08:36 PM

Yep, what he said

Matt Lehr

Posted: Mar 14, 2008 08:51 PM

OK. The smell has almost gone. The company did come back and core out all the air pockets and refoamed. What should I look for as far as failing foam if the mix is bad? and how soon?

Thanks

mason

Posted: Mar 15, 2008 08:50 AM

A-rich foam will be dark in color, higher density and more brittle. B rich foam will be lower density, lighter in color, softer and with cell deformation. B rich foam can shrink, have poor compressive strength, cause odors and not have sufficient R value, A rich foam can delaminate and easier, R value may be affected depending on the degree of off ratio blend.

A poor mix can cause problems also even if the foam is on ration. Poor mix would result in foam that has discoloration, cell deformation, odor, inconsistent compressive strength.

The fix to any of these problems is to identify the defective foam, remove it and re-foam.

NOTE: Open cell foamers who switch to closed cell foam typically make the same mistake, spraying the lifts of foam too thick. Closed cell foam should be sprayed in thickness between 1-2 inches, then let the foam set for about 10 minutes and build up additonal thickness. If you spray too thick a pass, exothermic heat can build up inside the foam, causing lower density, , separation, and even charring of the foam in extreme cases. Talk to your supplier about the best way to spray their foam.

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