Originally Posted by billyh
I just found out that my crawl space is considered a basement because the furnace ducting runs through it... despite being 5 ft high.
I had the basement sprayfoamed and I have to fire proof it (and not just cover it with an ignition coating).
Are my only options:
- Drywall (or similar)?
- Concrete (shotcrete)?
Drywall is not a great option, even the moisture resistant stuff, because the basement is a bit musty and there is sand.
Is it possible to DIY shotcrete at a reasonable price? Time is not an issue. I can take forever to do it.
or, is it possible to buy a fire rated spray foam and just spray on a surface layer?
Any other ideas?
Spray-applied rockwool. "FireStop TB" www.usfireproofing.com
material costs averages about .42 a sqft and is a true thermal barrier that protects the foam and not just a fire retarder like the coatings. It has been tested and approved over all manufactures open and closed cell spray foams and is considered an equivalant to drywall. It costs a 2/3 less than a coating.