Wall & Ceiling construction

[JunkMan]

I'm hoping to get started on my own TD after the first of the year, and need to decide exactly how I will build it. I plan on making "sandwich" type walls, so I can insulate them, and hopefully save a little weight.

Why does everyone seem to install the interior paneling after the sides and ceiling ribs are in place? Wouldn't it be easier to make the walls, complete with interior paneling, first, then wrap the ceiling over them, next add the cross ribs and insulation, then finally the roof?

Most of the construction pictures show people putting the ceiling paneling in after the ribs, then having to figure out some way of jaming or clamping it in place. Wrapping the ceiling first, then adding the ribs seems like it would be a lot easier.

If I use baltic birch for the ceiling, can I get away with just one layer in the ceiling, and 2 layers on the roof (do I really need 2 on the roof?). I plan on putting aluminum over the wood.

I noticed on one site that the builder used hardboard for the roof (under the aluminum). Would this be strong enough? Doesn't really seem like it would save much money. Any good reason to use hardboard?

[Steve Frederick]

Jack, Check out my journals. That's exactly how I build. I make the sandwich wall, at the same time creating a "ledge" for the headliner to rest on. The roof spars go on top of the headliner, glued/screwed in place. I also built all of the cabinets and bulkheads in place, as well as, varnish, before adding that headliner.

Mikes Lil'Diner

Cabinets in place.

Close-up of that ledge.

[asianflava]

Why does everyone seem to install the interior paneling after the sides and ceiling ribs are in place?

I think the Kuffel Creek instructions tell you to do it like that (I think, I'm not positive)
.

Wouldn't it be easier to make the walls, complete with interior paneling, first, then wrap the ceiling over them, next add the cross ribs and insulation, then finally the roof?

That's how I'm doing mine. I figure it will be a whole lot easier to access the cabinetry while there is no roof.

Most of the construction pictures show people putting the ceiling paneling in after the ribs, then having to figure out some way of jaming or clamping it in place. Wrapping the ceiling first, then adding the ribs seems like it would be a lot easier.

Unless you do a ledge like Steve, what would you clamp the ceiling to if there are no ribs?

If I use baltic birch for the ceiling, can I get away with just one layer in the ceiling, and 2 layers on the roof (do I really need 2 on the roof?).

I've asked this but nobody really knew why you needed 2 layers. I'm gonna just do 1 layer.

I noticed on one site that the builder used hardboard for the roof (under the aluminum). Would this be strong enough? Doesn't really seem like it would save much money. Any good reason to use hardboard?

I think you are talking about Steve W, John Walker, & Bruce I just checked the Hall of Fame and they all used hardboard. Steve glassed his afterwards so the fiberglass would add strength and water resistance. I think the advantage to using it is that it is easily available. I considered using it until I finally found some 1/8in ply locally. My main concern with using hardboard is it's water resistance or the lack of.

[bdosborn]

I think you are talking about Steve W, John Walker, & Bruce I just checked the Hall of Fame and they all used hardboard. Steve glassed his afterwards so the fiberglass would add strength and water resistance. I think the advantage to using it is that it is easily available. I considered using it until I finally found some 1/8in ply locally. My main concern with using hardboard is it's water resistance or the lack of.

I used hardboard for two reasons: I think its a bit more resiliant than the birch plywood and it bends really well. I'm concerned enough about water to coat it with spar urethane. But really, if you do a poor job of caulking the skin, you've still got problems with baltic birch or plywood since it doesn't stand up to water either. I tried to find finland birch (which is exterior rated) but couldn't find any locally so I ended up with the hardboard.

I'm going with one ply of 1/8" hardboard. I can sit on the hardboard with no problems. Unless you plan on dancing a jig on the roof, 1/8" seems plenty strong to me. Remember when you insulate the roof, its stressed panel construction and amazingly strong.

I totally agree with skinning the walls before adding the bows. I just didn't want to hassle with cutting the skin to fit around 7 or more bows, twice ( I seem to be dimensionally impared ). I skinned my walls first and the roofbows were a piece of cake to install.

I almost added the cabinets before I installed the roof but I didn't want to have to *exactly* place the cabinets so the headliner went in properly. The next one I build, I'm going to go with Steve's technique of installing the headliner. Super clean. I just wish he had posted his pictures about 3 months ago.

Welcome to my world, building a teardrop in your head every night.

Bruce

[JunkMan]

Thanks guys.

Steve, I think I asked you how you did your walls earlier. That is what I plan to do (build a ledge), but I just kept seeing web sites where others built theirs the other way. Do you varnish the ceiling before installing it also?

I want to get started building pretty soon, as I plan to have it done for the ITG in Nebraska, and knowing how I get things done, it will take me that long

I converted a school bus to a camper several years ago, and figured things out as I went along, and don't really want to do that again. It was a great learning experience, and will come in handy the next time I do something like that, but I would rather take advantage of everyone elses experiences if possible. Unfortunatly when I built the bus, I couldn't find a group like this one (which is made up of some really great people!) to help me out.

Next question: what type of moulding do you use for the outside roof / wall juncture? Is it the standard RV aluminum trim that has the vinyl insert or is it something different?

Thanks for all of the help so far, I'm sure that I will have more questions when I finally get started.

[Steve Frederick]

Jeff,
I didn't varnish that trailer before the headliner was installed. I will on the current project though. I didn't use any mouldings anywhere. I layed the headliner on that ledge, no gaps, no moulding! Outside, I faired the edge of the roof wood into the wall, then 'glassed that seam. No mouldings, no leaks!
On this project, we're still thinking about the roof, metal. wood, or even epoxy paint like Mike's Baja Benroy..Just the roof! What do you think?

[JunkMan]

I'm probably going to do the exterior of mine with aluminum. I would love to do a woodie, but I don't really have a place to do the fiberglass work, and the wife kind of likes the look of the aluminum ones. My other concern is weathering. I don't have a garage to store mine in, and I would hate to leave anything but an aluminum covered trailer exposed to the weather.

I guess I finally got the prodding I needed to get started today, the local lumber yard has 1/4" birch plywood on sale this week. I'll probably use it on the side walls, not sure if I want to make them 1 1/4" thick or 3" thick. I'll use the baltic birch for the ceiling, since it comes in 5' x 5' sheets, and I'm planning on making it 54" wide inside, so I can use a full sized mattress.

Not sure if I want to add a footwell. I'm only going to have about 43" interior height (less the matress) at the highest point. Would that be tall enough to have some type of dinette set-up? I might put one in just for storage, but don't really want to haul any more junk than I need. I know that I carry all kinds of extra stuff in my 5th wheel, mostly because I can.

[IslandStorm62]

Hello all,
I know this is an old post, but as I am a newbie...it's all new to me.

Anyway, hope there is some one out there available to offer advice.

I have a 1/2" Baltic Birch Exterior Wall, My internal framing is probably going to be 1x2s (assume premium pine) or cutouts from a 3/4" Maple paint stock board that was originally supposed to be a "cookie cutter" internal framing for my walls (sandwiched).

So the dilemma...I have 1/2" Baltic Birch Exterior wall with spars. I plan on using a 1/8" Baltic Birch Skin for the roof (nothing else except staining and Spar Varnish). How do I get this skin to stick to the wall and spars?

Use liquid nails alone? Would this be secure enough alone?
or

Do I need screws going through the skin into the spars?

or

Do I need screws going through the skin into the 1/2" Exterior Wall? Would this weaken the exterior wall (cause splitting)?

If I use screws, I supposed I will have to use some type of wood filler?

[Steve Frederick]

Here's what I would do. (have done)
It sounds like the spars will be exposed? If so, I would add a second layer of skin as follows;
First layer, good side down, pre finished if possible. let the edges overhang the wall by an inch or so. Glue and nail (I use a brad nailed) the skin to the walls and spars, being careful with nail placement. Glue the exterior skin to the interior, good side out. Don't use nails, but clamp the second skin to the edges of the first. You may need to improvise weights for the center. When all dry, trim the overhang flush to the sides with a flush-trim router bit. No fastener holes, just finish the edges as desired.


I hope this helps.

[IslandStorm62]

Wow,
You have twice as many clamps as my brother . You trust that glue to hold the second skin onto the first?

Do you have an interior wall skin? Does it extend all the way to the galley? And, if you do,how did you trim it to compensate for the spars and galley hatch?

I have a 1/2" Baltic Birch exterior, 1x2 (3/4") wall studs (so to speak) with insulation and then there will be a 1/8" Baltic Birch Skin. I'm just not sure how cut the internal wall skin, so when it is time to close the wall, it will to fit it to the wall with the spars overhead and not interfere with the hatch.

[aggie79]

If Steve's method works for you, I'd use it.

I used a different method that may also work. First, I cut two 1-1/2" "ribs" that matched the profile of my teardrop - one for each side. I temporarily held these in place with clamps to the sidewall. (They are flush with the top of the sidewall.)



I fitted the spars (to length) and then fastened the spars to ribs using pocket screws. I used two pocket screws at each end of the spars. The pocket screws were deep enough to fasten to the ribs but not penetrate further into the sidewalls.



Then I used screws to fasten some temporary strapping (made from scrap 1/8" plywood) to the ribs and spars to keep everything square and in alignment.



I then unclamped the ribs and removed the roof assembly to attach the "ceiling side" plywood and hull liner.



The roof assembly was put back and clamped into place. I then did the following on one side at a time. Remove the clamps. Spread apart the roof assembly and sidewalls. Add a bead of PL Premium adhesive. Realign and re-clamp roof assembly and sidewall. Then I removed one of the two pocket screws on each side and replace them with longer pocket screws that penetrated into the side walls. Finally I installed one deck screw on each side of the spars that ran from the outside of the sidewall, and through the sidewall and rib into the spar.



Sounds more complicated than it was.

Take care,
Tom

[IslandStorm62]

Thanks, unfortunately my woodworking skills are not... I'm having a heck of a time just cutting the arch/spars for my hatch.