We have a 1980
Trillium 5500
fiberglass trailer with a sagging roof, caused by and old 1989 air conditioner. So far, we have used square aluminum tubing, placed across the roof to lift the air conditioner (thereby reducing the sag) and stop the pooling of water underneath. For the winter, we have supported the roof underneath with a board across the bottom of the air conditioner, then supported by an upright below (to prevent a snow load from doing more harm). Our plan is to remove the air conditioner in the spring, replacing it with a clear roof window with a sliding blind.
Our concern is that we will not be able to flatten the roof sufficiently to have a good seal and not allow water to pool in the area.
Any help with this problem would be appreciated. The thickness of our roof is only 3/8 inch -- no strength for anything of
weight.