Ceiling ventilation fan

[Atridox]

I want to install a ceiling ventilation fan. CampingWorld has them but the install guy says that cutting a hole in the bus is different than cutting a hole in an RV since the RV ceiling is a single ply but the bus roof is two ply (out skin and interior roof). If so, do I need some type of flashing for the inside? How thick is the layer between the two plys of the school bus? Does anyone make a fan specifically for school bus? It is an 87 BlueBird on a Chevy C-60. Thanks, as always.

[lornaschinske]

Originally Posted by Atridox

... CampingWorld has them but the install guy says that cutting a hole in the bus is different than cutting a hole in an RV since the RV ceiling is a single ply but the bus roof is two ply (out skin and interior roof)...

Interesting since most RVs have an interior ceiling. It's just luan in our case. But cutting thru should be similar. Drill thru both layers in the corner of your proposed cut out (from outside) and make sure you are drilling straight down. Then use a straight edge to "connect the dots". Should be about 2" and you should have a trim piece for the interior. Flashing should already be part of the fan which installs from the exterior.

[Atridox]

Thank you, as always