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Nic Andermann Posted: Aug 25, 2008 10:09 PM	Las Vegas Attic Questions Hello, I'd like to DIY my attic but I have a few questions about all this web surfing I've done. First my roof is tile, so I'm assuning I don't have to worry about decreasing the life of the tiles if I spray the upper deck/seathing, correct?? But do I have to worry about the heat on the plywood and fire?? (Mainly because of the 115 outside temps here)?? Second the attic is vented and houses the upstairs AC/Furnace. I know it's the AC unit but I'm not posative that it's also the furnace (I haveen't looked at it that closely due to the heat in the attic). Now changing the attic to a non-vented space is easy enough, but is it recomended due to the AC/Furnace in the attic?? If it's just the AC unit can I get away with a non-vented space more so that if it's both units?? Third, If all of the above is ok IE. I don't have to worry about fire on the roof deck, and it's ok to change to a non-vented attic, Do I use a closed cell or an open cell product?? And Fourth What's the difference between 1lb. and 2lb. product?? Any info would be a great help Thanks Nic
mason Posted: Aug 27, 2008 01:48 PM	I would recommend going to my website, masonknowles.com and reading my articles on learning the differences between 1/2 lb and 2 lb SPF. There are also very good articles on vented and unvented attics on my blog. I am not a fan of DIY using SPF. Outside of small application like sealing your doors and windows, the application of SPF is a fairly technical field that requires a significant amount of training. The application of SPF in an unvented attic situation will not (contrary to shingle manufacturer's claims and exclusions) seriously affect the overall temperature and life of an asphalt shingle. It has no effect on tile or plwyood. All foam plastics must be oovered with a code approved igntional barriers in attics and crawl spaces (1-1/2 inch of mineral fiber, 1/4" wood and a few other materials.) Some coatings have been tested and approved over foam in attics. In order to use them a code official will want to see a ICC Evaluation Report on the specific foam and coating currently dated.

Author

Comments

Nic Andermann

Posted: Aug 25, 2008 10:09 PM

Las Vegas Attic Questions

Hello,

I'd like to DIY my attic but I have a few questions about all this web surfing I've done.

First my roof is tile, so I'm assuning I don't have to worry about decreasing the life of the tiles if I spray the upper deck/seathing, correct??
But do I have to worry about the heat on the plywood and fire?? (Mainly because of the 115 outside temps here)??

Second the attic is vented and houses the upstairs AC/Furnace. I know it's the AC unit but I'm not posative that it's also the furnace (I haveen't looked at it that closely due to the heat in the attic).

Now changing the attic to a non-vented space is easy enough, but is it recomended due to the AC/Furnace in the attic??

If it's just the AC unit can I get away with a non-vented space more so that if it's both units??

Third, If all of the above is ok IE. I don't have to worry about fire on the roof deck, and it's ok to change to a non-vented attic, Do I use a closed cell or an open cell product??

And Fourth What's the difference between 1lb. and 2lb. product??

Any info would be a great help

Thanks Nic

mason

Posted: Aug 27, 2008 01:48 PM

I would recommend going to my website, masonknowles.com and reading my articles on learning the differences between 1/2 lb and 2 lb SPF. There are also very good articles on vented and unvented attics on my blog.

I am not a fan of DIY using SPF. Outside of small application like sealing your doors and windows, the application of SPF is a fairly technical field that requires a significant amount of training.

The application of SPF in an unvented attic situation will not (contrary to shingle manufacturer's claims and exclusions) seriously affect the overall temperature and life of an asphalt shingle. It has no effect on tile or plwyood. All foam plastics must be oovered with a code approved igntional barriers in attics and crawl spaces (1-1/2 inch of mineral fiber, 1/4" wood and a few other materials.) Some coatings have been tested and approved over foam in attics. In order to use them a code official will want to see a ICC Evaluation Report on the specific foam and coating currently dated.

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