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nita ostermann Posted: Aug 19, 2008 05:14 PM	Florida house, board (not ply/OSB) roof deck Hello; i am interested in applying the foam to my roof deck for its adhesive (holds roof structure together during severe weather) and insulative properties. I am concerned, however, that the foam will expand between the boards of the roof deck and push up the asphalt shingles. has anyone dealt with that?? many thanks, DIY dolfan!
Posted: Aug 20, 2008 06:21 PM	My suggestion would be to first to decide on the type of foam you would like to use. We spray both. If your concern is additional racking (structural) strength along with outstanding insulation qualities, then use what we refer to as a 2 lb. foam. The boards should fit well and should be covered with an appropriate heavy felt or suitable substitute. The shingles should be in place before the underside of the roof is sprayed. If the felt or substitute is in place, the boards are properly fitted, and the shingles are in place, you shouldn't have a problem with the expansion forcing your shingles up. The clamps commonly used for OSB and for plywood decking have spacing similar to what you're talking about with your boards. Don't try it without the finished shingles, etc in place. Open cell foam will insulate well, allow you to discover a leak in the roof deck, and save you some money; however, if additional strength is required, use the 2 lb., and put the roof shingles on before the insulation is added. Good luck, We still remember the three storms that rolled through Florida that revealed the additional structural strength that could be realized by adding foam insulation to a home.
nita ostermann Posted: Aug 20, 2008 07:24 PM	Thank you Talon! the house was built in 1950 and the roofing is approximately 7 years old, in good shape. So is the roof deck, but i was afraid the foam would push thru any spaces between the boards thru to the shingles. But if you say it expands towards the path of least resistance, i.e. the deck underside, then I will be happy to spray it. "Stick" construction needs all the help it can get! And if you work in central FLA you can provide me a quote, if you like. I plan on another DIY project to save money but may consider a contractor. Thanks again, dolfan
Posted: Aug 26, 2008 06:20 PM	dolfan, Sorry, I didn't get back to you sooner. I look at the Spray Foam site as part of my late evening or early morning break in the day, and I've had very few leisure moments lately. Which is good. We're in Texas, but I'm sure you can find a good foam insulator in your area. We're not all trying to beat each other up or stab each other in the back. Sometimes we tend to forget that Salesmen are people, and some are a tad more honest and trust worthy than others. There are good hardworking salesmen with good products just as there are others with questionable products and services. Foam insulation will allow you to control the efficiency of your home. We've used the foam to help convert old barns into churches, and even Texas sized night clubs. Old school houses which were over 100 years old have been converted into homes. Without the foam, these projects would have been extremely difficult. Your project resembles other projects that we have worked on. Your HVAC professional should size your system and allow for the efficiency of the foam. Again, good luck to you, and when you see how well your home performs with the foam, tell a friend. We can all use the publicity.
nita ostermann Posted: Aug 26, 2008 06:42 PM	No apologies needed, we all have to work sometime ;) thank you again for your insight. i will let you know if i DIY or contract it. Keep up the good work in Texas- and yes, i have already gotten my coworkers excited about the idea of spraying their roof deck. take care!

Author

Comments

nita ostermann

Posted: Aug 19, 2008 05:14 PM

Florida house, board (not ply/OSB) roof deck

Hello;
i am interested in applying the foam to my roof deck for its adhesive (holds roof structure together during severe weather) and insulative properties. I am concerned, however, that the foam will expand between the boards of the roof deck and push up the asphalt shingles. has anyone dealt with that??
many thanks, DIY dolfan!

Posted: Aug 20, 2008 06:21 PM

My suggestion would be to first to decide on the type of foam you would like to use. We spray both. If your concern is additional racking (structural) strength along with outstanding insulation qualities, then use what we refer to as a 2 lb. foam. The boards should fit well and should be covered with an appropriate heavy felt or suitable substitute. The shingles should be in place before the underside of the roof is sprayed. If the felt or substitute is in place, the boards are properly fitted, and the shingles are in place, you shouldn't have a problem with the expansion forcing your shingles up. The clamps commonly used for OSB and for plywood decking have spacing similar to what you're talking about with your boards. Don't try it without the finished shingles, etc in place.

Open cell foam will insulate well, allow you to discover a leak in the roof deck, and save you some money; however, if additional strength is required, use the 2 lb., and put the roof shingles on before the insulation is added.

Good luck, We still remember the three storms that rolled through Florida that revealed the additional structural strength that could be realized by adding foam insulation to a home.

nita ostermann

Posted: Aug 20, 2008 07:24 PM

Thank you Talon! the house was built in 1950 and the roofing is approximately 7 years old, in good shape. So is the roof deck, but i was afraid the foam would push thru any spaces between the boards thru to the shingles. But if you say it expands towards the path of least resistance, i.e. the deck underside, then I will be happy to spray it. "Stick" construction needs all the help it can get! And if you work in central FLA you can provide me a quote, if you like. I plan on another DIY project to save money but may consider a contractor.
Thanks again, dolfan

Posted: Aug 26, 2008 06:20 PM

dolfan,

Sorry, I didn't get back to you sooner. I look at the Spray Foam site as part of my late evening or early morning break in the day, and I've had very few leisure moments lately. Which is good. We're in Texas, but I'm sure you can find a good foam insulator in your area. We're not all trying to beat each other up or stab each other in the back. Sometimes we tend to forget that Salesmen are people, and some are a tad more honest and trust worthy than others. There are good hardworking salesmen with good products just as there are others with questionable products and services. Foam insulation will allow you to control the efficiency of your home. We've used the foam to help convert old barns into churches, and even Texas sized night clubs. Old school houses which were over 100 years old have been converted into homes. Without the foam, these projects would have been extremely difficult. Your project resembles other projects that we have worked on. Your HVAC professional should size your system and allow for the efficiency of the foam. Again, good luck to you, and when you see how well your home performs with the foam, tell a friend. We can all use the publicity.

nita ostermann

Posted: Aug 26, 2008 06:42 PM

No apologies needed, we all have to work sometime ;) thank you again for your insight. i will let you know if i DIY or contract it. Keep up the good work in Texas- and yes, i have already gotten my coworkers excited about the idea of spraying their roof deck.
take care!

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