Mounting ceiling panels

Hi all. 2019 Promaster 2500 159", currently bare. Looking for opinions on mounting ceiling panels. The cross ribs are annoyingly unevenly spaced, which would lead to strange panel widths if screwed into firring on those ribs. One builder recommended placing evenly spaced ribs on the roof, built from expanded PVC, secured with strong marine urethane adhesive. In the Promaster, this means expanded PVC 1 inch thick, which is expensive. So, why not jsut use the urethane adhesive to affix 3" wide strips of 1" thick wood to the ceiling steel, and use those to attach the interior ceiling panels (likely 1/4" plywood, or 3 mm)

On a separate note, we are just back from 18 months in New Zealand, a good part of that in campervans. A unique feature to NZ housetrucks is people put woodstoves in them - quite a site to see a housetruck lumbering down the road, wood smoke coming out of the stack! How come no one does that here? :slight_smile:

Greetings & Welcome!

Why not just fill the voids between the ribs with cheap foam insulation sheets cut to fit, then attaching your panels to the ribs. If you don’t like the uneven look of the screws, add rows of non functional screws just to even it out.

It’s not that you can’t add wooden, or even metal ribs, the question is whether or not you need them, or even furring strips. After the blank floor/walls/ceiling are finished to my satisfaction, I will then add additional support beams screwed into the now hidden ribs to support furniture, cabinets, etc. which in turn will hide those added support beams. This method seems to allow for nearly unlimited flexibility.

I don’t like putting wiring inside my walls either, preferring hidden but easily accessible interior channels instead. I run my wires along the tops & bottoms of my walls, hidden by trim.

Whenever possible, I like to keep my interiors modular & portable, but secured. This way you can change your layout with minimal effort.


"There are those who learn, and those who wish they had learned." ~ Good2Know

Insulation is a whole different discussion, but… the steel of the roof ribs is subject to vibration, and sheet metal screws could back out, from what I’ve been told. Better to have wood to screw into, which damps vibration. The other issue, as noted, is that the ribs are wierdly spaced, leading to inefficient wood use, and funky appearance. But, the question remains, can marine adhesive hold WOOD, instead of Expanded PVC to the sheet metal roof? Thanks!


I haven’t heard of any problems screwing into the ribs. Some people do use rivnuts though.

“Marine Adhesive” isn’t enough to guess on. Some might, and some might not. Some adhesives are pretty specific about what they’ll work with, some are not. I have used “Liquid Nails” successfully long ago.


"There are those who learn, and those who wish they had learned." ~ Good2Know

We simply ran furring strips perpendicular to the ribs and secured them with self tapping metal screws. We have not had an issue in 2 years on the same exact van as yours and we’ve seen some pretty gnarly washboard over that time. If it makes you feel better you could put a few dabs of liquid nails wherever they make contact. Thinking about it once you cover those there is really no room for them to back out. We just used half inch ply cut into strips. The same as we did for the walls and have had zero issues there as well.

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