My roof was sagging pretty bad. Removed the 1x2 strapping and replaced with 2@ 2x4 , 2@ 2x3,and the ends with 2@2◊2. Roof is solid enough person could walk up there if need be. I'm planning on mounting solar
panels, and maybe a kayak rack up there. My door was also sagging. The longer part of the hinge was worn. I tried finding roll pins big enough, but couldn't find any that would work. I ended up drilling the holes to accept automotive door pins with bushings. The pins need to be shortened but the door no longer sags, feels very solid , and if it wears out all I need to do is replace bushings.