8 lb CC Foam for structural use?? | Ask Mason Knowles - SPF Consultant | Spray Foam Technical Questions and Answers | SprayFoam Magazine Q&A Forums

Q&A Forums

8 lb CC Foam for structural use?? Post New Topic | Post Reply

Author	Comments
Kyle & Son Posted: Aug 04, 2014 07:18 PM	8 lb CC Foam for structural use?? I have a potential customer that wants me to apply 8lb CC foam at 4" to create a dome-like structure. Does anyone have any experience with this kind of foam? Can it even be sprayed? The only stuff I have found is pour in place with a density that high. Any ideas are appreciated.
mason Posted: Aug 07, 2014 03:15 PM	An 8 lb density foam would have significant compressive strength however, it also would be more susceptible to fractures. I have sprayed a 6 lb foam that was used for various purposes. One in particular was a blank for a surfboard. Unfortunately it broke in half on a wave in Hawaii. As the foam's density gets higher, it also gets less flexible and more prone to break and fracture. Domes have been made with spray foam for decades. A regular 2 lb or 3 lb foam with reinforcement works pretty well. Check out Domes Institutes website. David South has been building foam domes since the 70s. He inflates a vinyl air form, sprays 3-4 inches of foam to the inside of the structure, then adds rebar reinforcement and sprays the foam with shotcrete. Then the vinyl in removed and the outside finished with a suitable exterior covering.

Author

Comments

Kyle & Son

Posted: Aug 04, 2014 07:18 PM

8 lb CC Foam for structural use??

I have a potential customer that wants me to apply 8lb CC foam at 4" to create a dome-like structure. Does anyone have any experience with this kind of foam? Can it even be sprayed? The only stuff I have found is pour in place with a density that high. Any ideas are appreciated.

mason

Posted: Aug 07, 2014 03:15 PM

An 8 lb density foam would have significant compressive strength however, it also would be more susceptible to fractures.

I have sprayed a 6 lb foam that was used for various purposes. One in particular was a blank for a surfboard. Unfortunately it broke in half on a wave in Hawaii. As the foam's density gets higher, it also gets less flexible and more prone to break and fracture.

Domes have been made with spray foam for decades. A regular 2 lb or 3 lb foam with reinforcement works pretty well. Check out Domes Institutes website. David South has been building foam domes since the 70s. He inflates a vinyl air form, sprays 3-4 inches of foam to the inside of the structure, then adds rebar reinforcement and sprays the foam with shotcrete. Then the vinyl in removed and the outside finished with a suitable exterior covering.

You need to login to reply to this topic. Please click here to login.