the heat from the sun will warp, not telling you what I think telling you what I know, went through it not long ago. Like I said if its not in the direct sunshine all day it will do better, if its in the direct sunshine all day it will warp. Maybe with it being winter time it will do better, mine did this in the summer and was in direct sun most of the day, used at least 1 1/2 inch stuff too.