Tuesday, March 1, 2011

Bus Blog 11: Sealing the Ceiling

To save several days spent drilling out rivets, we decided to leave the tin ceiling in place.  There was already a modicum of insulation behind it and it would provide a good adhesive surface for the insulation we planned to install.  Height limitations made 1/2" rigid foam insulation seem the best choice and while only providing a R-3 insulative value, the existing ceiling, vapor barrier and Masonite panels we planned to install would significantly increase that number.  Just like dressing for winter, every little bit helps.
Prep was quick and easy, we pulled all the light housings and speakers, leaving the wires to dangle so they could later be pulled through the new ceiling.
With a little trimming the 4x8' sheets of pink insulation fit perfectly.  I applied generous amounts of PL to the backs, pressed them against the ceiling and screwed them in place with self-tapping drywall screws.  While the screws could easily pull though the pink foam, they provided sufficient gripping power to hold the panels up while the glue dried.
Applying the insulation was one of the more pleasurable tasks of the bus conversion process.  The panels were feather-light, the short height mean no arm fatigue, and it looked like we were getting a heck of a lot done.
Next, we began taping the plastic vapor barrier in place.  Since there was nothing for staples to grab, we ended-up cutting the plastic in strips and taping them to the ceiling, then each other.  Though cutting and resealing the vapor barrier is a bit counter intuitive, I wasn't going back to the hardware store.  We did our best to insure a good seal by overlapping the plastic a good amount and taping the heck out of it.
Though the tape threatened to pull the prints from our fingers, we were able to complete the ceiling by the end of the night.
A working day later, we continued the vapor barrier down to the floor.
It wasn't pretty but with Masonite and plywood holding the insulation and plastic in place, it should turn out alright.