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Edward Brassington Posted: Oct 06, 2008 08:44 PM	Another crawl space question Hello Mason. Thank you for providing this question and answer forum, it is very helpful. I read all the posts and gain a lot from them. Today I looked at an island cottage in Ontario, Canada for SPF in the crawl space beneath. The cottage is supported on piers with a wood frame wall around the perimeter. The house is also built over a large granite rock covered in vapour barrier. The cottage is used spring, summer and fall. All heat and water is to be turned of and drained for the winter. The hous is heated with electric baseboard due to the island location. There is no heat in the crawl space. I had suggested spraying the foundation wall with three inches of closed cell, The customer is concerned that the temperature of the rock will keep the floors cold well into June if I spray the foundation walls instead of the underside. Apparently Ice remains under the cottage until mid June or later, which of cours makes the floors cold well into the spring. There is plumbing under the cottage which will be boxed in and sprayed to protect against the cold spring and fall days and then drained for the winter. What would you recommend in this application. Thanks. Ed The Foammaker.
mason Posted: Oct 07, 2008 07:53 AM	I think your customer is right. The cold stone will act like a refrigerator and suck the warmth from the house. And the foam on the foundation walls will insulate it from the hot air. This would be a good thing in summer, but in Fall or Spring keep the house colder than you want. Spraying the underside of the house makes more sense. This would completely separate the interior and exterior environment. I did this on my mom's house in Houston and it works well both in summer and winter.
Eric Smith Posted: Oct 08, 2008 05:59 PM	I didn't think that you could spray the underside of the home, i.e. crawl space, without an ignition barrier.
mason Posted: Oct 09, 2008 09:15 PM	True, an ignition barrier is required in crawl spaces unless full scale fire tests have been conducted with the specific foam that demonstrates it is not required.

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Comments

Edward Brassington

Posted: Oct 06, 2008 08:44 PM

Another crawl space question

Hello Mason.

Thank you for providing this question and answer forum, it is very helpful. I read all the posts and gain a lot from them.

Today I looked at an island cottage in Ontario, Canada for SPF in the crawl space beneath. The cottage is supported on piers with a wood frame wall around the perimeter. The house is also built over a large granite rock covered in vapour barrier. The cottage is used spring, summer and fall. All heat and water is to be turned of and drained for the winter. The hous is heated with electric baseboard due to the island location. There is no heat in the crawl space.

I had suggested spraying the foundation wall with three inches of closed cell, The customer is concerned that the temperature of the rock will keep the floors cold well into June if I spray the foundation walls instead of the underside. Apparently Ice remains under the cottage until mid June or later, which of cours makes the floors cold well into the spring.

There is plumbing under the cottage which will be boxed in and sprayed to protect against the cold spring and fall days and then drained for the winter.

What would you recommend in this application.
Thanks.

Ed The Foammaker.

mason

Posted: Oct 07, 2008 07:53 AM

I think your customer is right. The cold stone will act like a refrigerator and suck the warmth from the house. And the foam on the foundation walls will insulate it from the hot air. This would be a good thing in summer, but in Fall or Spring keep the house colder than you want. Spraying the underside of the house makes more sense. This would completely separate the interior and exterior environment. I did this on my mom's house in Houston and it works well both in summer and winter.

Eric Smith

Posted: Oct 08, 2008 05:59 PM

I didn't think that you could spray the underside of the home, i.e. crawl space, without an ignition barrier.

mason

Posted: Oct 09, 2008 09:15 PM

True, an ignition barrier is required in crawl spaces unless full scale fire tests have been conducted with the specific foam that demonstrates it is not required.

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