Structural Insulated Panels in MH

[Myra]

I was watching Michale Holigan's Your New House and they were showing a new home they built out of SIP's. What I'm wondering is why some manufactured housing company hasn't taken up building MH out of this stuff? Seems to me it would save time (they said the whole house can actually be cut by computer at the factory and arrive ready to assemble...roof and all), increase energy efficiency and structural integrity. They said a 4-inch panel performs better than a 2x6 wall with R-19 batting. Are there any manufactured housing representatives listening? Seems like the industry should be taking note of this building material.