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Author	Comments
Bill Rice Posted: Oct 09, 2007 04:15 PM	Foam Shrinkage On two different jobs in two differing climates (New Mexico, and Missouri) we have had shrinkage of the foam to the point it is pulling up the metal edge foam stop and actually pulling the parapet walls to the point of cracking motar joints. We have over 30 yrs experiance with foam roofs and have never seen this before. It is a Government specification with six inches of foam at the edges, acrylic coating with granules added in the last two coats of coating. Anyone else having any shrinkage problems to this point?
Gerry Wagoner Posted: Oct 09, 2007 06:27 PM	We had a little edge reversion on a barrel roof two months ago, but fixed it no problem. Is the foam really six inches thick? olger
r Harris Posted: Oct 10, 2007 09:08 PM	I am aware of some potential roof foam shrinkage problems that have developed recently. Can you clarify whose foam was sprayed, what the substrates were and at what general ambient temperatures the foam was sprayed?
SprayFoamSupply.com Posted: Oct 20, 2007 06:10 AM	THe obvious question is are you sure that you were on ratio? On the 2 jobs, were they done with the same equipment or different equipment? Spraying the foam too thick in one pass or without enough time to cool between passes can result in lowering the density of the core foam. This can cause the foam to not be as dimensionally stable as it should be. How long after application did the shrinking start? George
Posted: Feb 11, 2008 03:49 PM	Yes I have had about 5000sqs shrink who was the manufacture of the foam? Did you put poly urea to the foam as the coating?
Posted: Feb 11, 2008 03:51 PM	was it over a concrete deck?
Posted: Apr 02, 2009 10:15 AM	Who was your supplier that this happened with? We may have the same suppier. I have only heard of a few us having this problem.
Posted: Apr 02, 2009 10:18 AM	The foam was sprayed to concrete decks on 9 different building at any were between 80-90 degrees each day.
Posted: Apr 02, 2009 10:24 AM	Bill, Send me an email to Buc-enterprises@msn.com Thank You

Author

Comments

Bill Rice

Posted: Oct 09, 2007 04:15 PM

Foam Shrinkage

On two different jobs in two differing climates (New Mexico, and Missouri) we have had shrinkage of the foam to the point it is pulling up the metal edge foam stop and actually pulling the parapet walls to the point of cracking motar joints. We have over 30 yrs experiance with foam roofs and have never seen this before. It is a Government specification with six inches of foam at the edges, acrylic coating with granules added in the last two coats of coating. Anyone else having any shrinkage problems to this point?

Gerry Wagoner

Posted: Oct 09, 2007 06:27 PM

We had a little edge reversion on a barrel roof two months ago, but fixed it no problem.

Is the foam really six inches thick?

olger

r Harris

Posted: Oct 10, 2007 09:08 PM

I am aware of some potential roof foam shrinkage problems that have developed recently. Can you clarify whose foam was sprayed, what the substrates were and at what general ambient temperatures the foam was sprayed?

SprayFoamSupply.com

Posted: Oct 20, 2007 06:10 AM

THe obvious question is are you sure that you were on ratio? On the 2 jobs, were they done with the same equipment or different equipment? Spraying the foam too thick in one pass or without enough time to cool between passes can result in lowering the density of the core foam. This can cause the foam to not be as dimensionally stable as it should be. How long after application did the shrinking start?

George

Posted: Feb 11, 2008 03:49 PM

Yes I have had about 5000sqs shrink who was the manufacture of the foam? Did you put poly urea to the foam as the coating?

Posted: Feb 11, 2008 03:51 PM

was it over a concrete deck?

Posted: Apr 02, 2009 10:15 AM

Who was your supplier that this happened with? We may have the same suppier. I have only heard of a few us having this problem.

Posted: Apr 02, 2009 10:18 AM

The foam was sprayed to concrete decks on 9 different building at any were between 80-90 degrees each day.

Posted: Apr 02, 2009 10:24 AM

Bill,

Send me an email to Buc-enterprises@msn.com

Thank You

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