Hello I have a home design with an almost flat roof (i.e. 1/4").
What can I specify in my design as an appropriate compound that will seal the roof and also look good?

I don't want to hear anything about a hot mop; I've heard to many manufacturers specify against it.  From what I know it's petroleum vapors will damage the foam. 

I am thinking of using a deck substrate but not sure what the best would be.

Does anyone have any case studies on this?

I am attaching a render of the house design.

Thanks,

Jeremiah
sipdesigns@cox.net

You can use a build up (tar and gravel) or modified (torch) for reasonable prices. Your foam won't be exposed to tar in a build up so this would not be an issue. There are also rubber roofs, but they will no doubt be more expensive.

It looks like you are going to cantilever the top floor out with the porch. I would be interested in seeing your engineering on this when complete. I have wondered about doing such a thing considering that a panel especially with a large unbroken header and footer should act like a beam. You have a large window on the second story left that could have some king studs to reduce your header needs. And it looks to me like those same windows go all the way to the floor. Are you aware that anything below 18" has to be tempered? I wouldn't want to pay for those monsters if that is the case.