How to attach wood to the ceiling?

[NRdomepiece]

I have been unsure of this for awhile and can’t find what I’m looking for.

I plan on ripping 1/2” plywood down and painting it white and doing a ship lap type ceiling. My question is, how do you attach the wood to the ceiling without having exposed fasteners?

I’m not even against exposed fasteners but with the umpteen million holes in each rib i think I’d have a lot of broken self tapers or gaps that weren’t even.

I’m having some closed cell foam sprayed on the walls and ceiling done Friday and would like to start on the ceiling ASAP after as it’ll be in the low 90s.

Thanks!

[HazMatt]

Attach furring strips to the hat channels.
I installed mine to the sides, to minimize further encroachment on the minimal headroom.
It helps to negate thermal bridging, and give you some nice, compliant wood to screw to.
I used some pretty, brass-finished Torx screws to attach the luaun panels to the furring, and pre-tapped to ensure uniformity.

[JustKip]

I'm with HazMatt. Attach wooden "ribs" to the existing ribs, then attach your finish ceiling to that. I know on guy who didn't even remove the metal ceiling...just screwed about 1.5 inch wood to existing, insulated that space, then attached tongue and groove siding

[NRdomepiece]

So to the bottom of the rib? Like a 1x2?

My bus has a tall ceiling but I’d like to maintain as much headroom as possible.

[HazMatt]

Presupposing the steel ceiling panels are gonzo: the hat channel surfaces, along the top curvature, which are perpendicular to the ground.
Front n back faces, if you like...
Zero loss of head space, like would happen by attaching the furring on the inwards-facing hat channel faces.
I found screwing my furring strips on only one side of each rib to be more than adequate to attach my thin, finished plywood to.
Mine was several mm thick, but I'm confident your thicker lapboard treatment would fare equally well.
PS: Yes, 1" x 2"

[NRdomepiece]

Yes the ceiling panels are gone. I’m having some 1” thick closed cell foam sprayed on the ceiling and walls on Friday.

[o1marc]

To avoid fasteners showing, I'm using a construction adhesive. That will hold my weight hanging from it, between 2 ribs. But can be pried loose if access is needed. I avoided as much wiring under those panels as possible, incase I have to go back in there someday.
Here's the neighbors kid hanging from a glued piece of 2 x 2. I cut curved "T" braces to hold the panels wedged against the ceilng.

[HazMatt]

If you go my route, installing those strips will be mondo easier before the bus starts foaming at the mounds...
It is a time-consuming process, however.
On consideration, you may want to reschedule...

[PNW_Steve]

Originally Posted by o1marc

To avoid fasteners showing, I'm using a construction adhesive. That will hold my weight hanging from it, between 2 ribs. But can be pried loose if access is needed. I avoided as much wiring under those panels as possible, incase I have to go back in there someday.
Here's the neighbors kid hanging from a glued piece of 2 x 2. I cut curved "T" braces to hold the panels wedged against the ceilng.

Marc,

What adhesive are you using?

I have tried the Liquid Nails Construction Adhesive from the big box stores and found it to be nearly useless

I had considered using 3M 5200 but have never tried using it with wood.

Thanks.

[o1marc]

Originally Posted by PNW_Steve

Marc,

What adhesive are you using?

I have tried the Liquid Nails Construction Adhesive from the big box stores and found it to be nearly useless

I had considered using 3M 5200 but have never tried using it with wood.

Thanks.

I thought I had discussed it in my build thread, but after 20 minutes of searching, it's not there. I'm pretty sure its a LocTite product. Here I am hanging my whole 165lbs from it about 20 minutes after gluing it up.

[musigenesis]

Originally Posted by HazMatt

Presupposing the steel ceiling panels are gonzo: the hat channel surfaces, along the top curvature, which are perpendicular to the ground.
Front n back faces, if you like...
Zero loss of head space, like would happen by attaching the furring on the inwards-facing hat channel faces.
I found screwing my furring strips on only one side of each rib to be more than adequate to attach my thin, finished plywood to.
Mine was several mm thick, but I'm confident your thicker lapboard treatment would fare equally well.
PS: Yes, 1" x 2"

Found this handy diagram of what the parts of a hat channel are called: https://www.researchgate.net/figure/...fig3_320073695

They've got one top, two sidewalls and two flanges. You're talking about attaching the furring strips to the sidewalls, right? So that they're flush with the hat channel's top?

[Ciscokid]

you must have some really good shocks. Our bus rides like a Sherman tank and after that trip from east coast to Denver my ceiling would have been flooring if it was glued.

[HazMatt]

Originally Posted by musigenesis

Found this handy diagram of what the parts of a hat channel are called: https://www.researchgate.net/figure/...fig3_320073695

They've got one top, two sidewalls and two flanges. You're talking about attaching the furring strips to the sidewalls, right? So that they're flush with the hat channel's top?

Well, I suppose... If you just GOTTA use the proper nomenclature..!
Attached to one sidewall per rib, as close to flush with it's top as the curvatures permit.
It took 5 short pieces to fill the wall/roof transition, bevel cut at a variety of angles to allow butt fits together.
Not for nothing, I attached to the aft sidewalls starting at the e-hatch, back, and the fore sidewalls foreward of the hatch.

[musigenesis]

Originally Posted by HazMatt

Well, I suppose... If you just GOTTA use the proper nomenclature..!
Attached to one sidewall per rib, as close to flush with it's top as the curvatures permit.
It took 5 short pieces to fill the wall/roof transition, bevel cut at a variety of angles to allow butt fits together.
Not for nothing, I attached to the aft sidewalls starting at the e-hatch, back, and the fore sidewalls foreward of the hatch.Attachment 35917

A pic is even better than proper nomenclature! How did you insulate?

[HazMatt]

Originally Posted by musigenesis

A pic is even better than proper nomenclature! How did you insulate?

Half inch foam board glued to the ceiling (a series of 1/4"-spaced kerfs to make the curve), air gap, Reflectix atop hat channels (held in place with a few staples into the fur), and that backed up against the finished luaun panels.

[Bluetoad]

Gonna hi-jack the thread for a second to ask my own questions since the topic is raised. I plan on doing this as well...I saw a build on youtube where his wood ceiling ended up flexing and he got waves in his ceiling. Has anyone run into that issue before and is just glue and nails and letting the wood acclimate the proper procedure?

[Frogpondfoug]

I used tounge n groove cedar which was sealed on bo h sides. Screwed with stainless screws. Holds good

[NRdomepiece]

Originally Posted by Ciscokid

you must have some really good shocks. Our bus rides like a Sherman tank and after that trip from east coast to Denver my ceiling would have been flooring if it was glued.

What did you used to glue and screw to? Is that 1/2 plywood?

The issue I’m seeing is the ribs on my bus are about 28” apart. So putting a 4’ wide sheet up would require something in between the sheets.

I’m thinking about buying some metal siding with a 5/8” rib and putting it up the length of the bus. Then I can glue and screw any length of wood to the ceiling. .