afreegreek wrote:that will work fine but you're better off putting some fasteners along your "spars" too at least until your adhesive cures.. after, you can take all the fasteners out if you want to as long as you got everything positioned before the adhesive skinned over.. a good bead of PL is 10x more than you need and the screws serve no purpose other than attracting moisture..
That is how I fastened my 1/8" ply roof. For the screws, I used the self-drilling screws so I didn't have to drill pilot holes. The screws didn't fully penetrate the spars.
Since I was covering the roof (and sidewalls) with aluminum, I found it handy to mark the location of the spars and electrical runs on the plywood so I didn't put any fasteners where they didn't need to be.
After the PL Premium set, I removed the screws, and filled the holes.
Take care,
Tom