The risk of doing something you’ve never done before can result in problems. I appear to have bent the top skin of the van slightly when installing the vent. Metal bends…You can imagine sitting on the ceiling and leaving a dip. The force of screwing the self tapping screws down pressed a dip into the van roof. Crap… I should have predrilled them.
Fortunately, there is an easy fix… a very easy fix. Soon I will be installing the insulation and ceiling in the Express. When doing that, I will be screwing longitudinally placed furring strips into the lateral roof ribs… To raise the ceiling back up, I will add wood shims under the furring strips to raise the vent area at or ever so slightly above the original height. There will be pictures taken so you can see how I fixed it. A little icing on the cake is that at that time I will either glue or screw the shims to the furring strips to ensure they never shift. If I use the same thickness of shims, the roof should be raised equally on all four signs.
Advice… Go lightly if you have to install a roof vent. Don’t put too much weight on the roof… It is metal and it will bend. But rest assured you can fix it too. It’s not rocket science and mistakes will happen. Learning is not without pain but mastering something feels so good when you do it!