Metal Roof Decking Instead of Plywood Sheathing
Has anyone ever seen or installed steel decking over 2x rafters instead of plywood/OSB sheathing? Considering the price of lumber right now, the idea came to me after coming across some corrugated metal on the Lowe’s website.
I have seen a similar application on a commercial building I was Superintendent/PM over, but the trusses were 2x light gauge metal on 4 or 5:12 pitch (this project was a few years ago). The building had a 18,000SF footprint and was LEED Certified, so I know the idea is acceptable practice but I cannot find anything online about this being applied to a wood framed (or) residential building.
My application would be for a small cabin with a 9:12 pitch with rafters on 24″ centers. Like the commercial building, I would like to install polyiso board over the decking, ice and water shield, and just a cheap residential metal roof on it.
Does anyone see a problem with this? What gauge metal could I get by with? The commercial application use 22ga metal but the trusses were on 4′ centers. I’m hoping to get by with something lighter gauge off the shelf that’s considerably cheaper. Any thoughts on what to keep in mind?