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Rob Granger Posted: Feb 28, 2008 07:12 PM	Off Ratio Symptoms Mason, I got called to diagnosis a problem today where the occupants of a wood frame building are smelling an ammonia type smell near the back door of their building. The smell is strong when it is real cold out such as today when it started out a 5 degrees and rose to only about 10 degrees. The basement is mostly of a dirt floor ranging from 1 foot to 5 foot clearance. A third of the space was sprayed foamed with about 2 inches cc to the floor deck and 3 inches cc to the sidewalls. It was sprayed in late September according to the owner. It is moist at times in the space as surface water can make its way into the crawl. There is lime on the dirt floor seemingly from attempts to keep the musty smell down. The owner wonders if it is the foam or the possibility that some animals have taken refuge in the crawl especially during cold temps and are of course unrinating. The front of the bldg was sprayed and the acess is in a bathroom near the front. The smeel is noticed again at the rear door well away from the sprayed part. Doe off ratio smell of ammonia? If it does it semms like the occupants would have smelled it long ago as agin the access is in the bathroom and the door to the crawl is not airtite. I have not questioned the original sprayer. In Mason absence any one can comment. I am also looking for his comments upon return.. Thanks
mason Posted: Feb 29, 2008 01:36 PM	Odor coming from sprayfoam can be a sign of off ratio mix. The ammonia odor can be a tip off of a B rich formula. That odor is usually associated with catalyst. Take some random core samples and check out the compressive strength of the foam. A 2 lb closed cell foam should have at least a 15 psi compressive strength or higher. If there are soft spots, it is likely off ratio, B rich and would have an odor. However, the odor from foam would be more noticeable in warm weather not cold. So I suspect the varmints may be causing the problem and not the foam.
Matt Lehr Posted: Mar 02, 2008 08:44 AM	I just had 1/2lb sprayed and an awful order is still in the air for 4 days now. Windows are open and its 32 degrees outside. Will this smell go away and what else should I look for for proper install.
mason Posted: Mar 02, 2008 09:02 AM	Look for elongated cells, voids, cracks and seperations in the foam. All of these can be signs of a poor mix. When spraying in cold weather particular attention must be given to storing materials in warm conditions and bringing the liquid components in the drum to the temperature recommended by the manufacturer before starting to spray. This can vary from foam to foam. I have seen some foams that require the foam in the drums be at least 100 degrees F before transfering to the proportioner. Others can handle a good mix at around 60 degrees F. Also, remember it takes a while to heat a drum, 3-4 hours with a band heater and at least 30 minutes to an hour when recirculating it through your proportioner heaters.

Author

Comments

Rob Granger

Posted: Feb 28, 2008 07:12 PM

Off Ratio Symptoms

Mason, I got called to diagnosis a problem today where the occupants of a wood frame building are smelling an ammonia type smell near the back door of their building. The smell is strong when it is real cold out such as today when it started out a 5 degrees and rose to only about 10 degrees. The basement is mostly of a dirt floor ranging from 1 foot to 5 foot clearance. A third of the space was sprayed foamed with about 2 inches cc to the floor deck and 3 inches cc to the sidewalls. It was sprayed in late September according to the owner. It is moist at times in the space as surface water can make its way into the crawl. There is lime on the dirt floor seemingly from attempts to keep the musty smell down. The owner wonders if it is the foam or the possibility that some animals have taken refuge in the crawl especially during cold temps and are of course unrinating. The front of the bldg was sprayed and the acess is in a bathroom near the front. The smeel is noticed again at the rear door well away from the sprayed part. Doe off ratio smell of ammonia? If it does it semms like the occupants would have smelled it long ago as agin the access is in the bathroom and the door to the crawl is not airtite. I have not questioned the original sprayer. In Mason absence any one can comment. I am also looking for his comments upon return.. Thanks

mason

Posted: Feb 29, 2008 01:36 PM

Odor coming from sprayfoam can be a sign of off ratio mix. The ammonia odor can be a tip off of a B rich formula. That odor is usually associated with catalyst. Take some random core samples and check out the compressive strength of the foam. A 2 lb closed cell foam should have at least a 15 psi compressive strength or higher. If there are soft spots, it is likely off ratio, B rich and would have an odor.

However, the odor from foam would be more noticeable in warm weather not cold. So I suspect the varmints may be causing the problem and not the foam.

Matt Lehr

Posted: Mar 02, 2008 08:44 AM

I just had 1/2lb sprayed and an awful order is still in the air for 4 days now. Windows are open and its 32 degrees outside. Will this smell go away and what else should I look for for proper install.

mason

Posted: Mar 02, 2008 09:02 AM

Look for elongated cells, voids, cracks and seperations in the foam. All of these can be signs of a poor mix. When spraying in cold weather particular attention must be given to storing materials in warm conditions and bringing the liquid components in the drum to the temperature recommended by the manufacturer before starting to spray. This can vary from foam to foam. I have seen some foams that require the foam in the drums be at least 100 degrees F before transfering to the proportioner. Others can handle a good mix at around 60 degrees F. Also, remember it takes a while to heat a drum, 3-4 hours with a band heater and at least 30 minutes to an hour when recirculating it through your proportioner heaters.

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