Wall sheathing, choice of material?

[JackConrad]

I use 1/2" SandaPly.  It is relatively lightwwight, very smooth surface, and more pys than standard BC plywood. It is available at Home Depot, Lowe's and probably other building supply places. Instead us using roofing felt, I applied a heavy bead of polyurethane adhesive to all framing members and used a lot of screws.  Jack

[David Anderson]

While were talking about walls!

Nick turned me on to the idea of using body filler on the joints, worked perfect. 

Cliff

Nick and Cliff,

I used wallboard compound to cover the joints in my sheathing.  It covered them very well, but after about 4 years every joint cracked from bus contracting/expanding.  This played havoc with the wallpaper my wife liked so much.  I had to remove all the paper and glue up carpet.  I'm thankful I painted the plywood with Kilz before installation or that paper removal would have been awful.

However, in the kitchen we had originally installed a very thick vinyl paper that simulates ceramic tile and it has held up well.  Only if you look really closely you will be able to see the sheathing crack. 

I feel like body filler would have had similar results over time unless it can flex with the bus.

David

[coachconverter]

I would agree, body filler or wood putty will crack after drying, especially after flexing going down the road, and even more so after experiencing numerous 100+ degree variations every season.

Before I started my conversion shop, I spent about 10 years learning as much as I could from you fine folk here, other owners of conversions, from dismantling previous conversions and from talking directly to experienced converters.  One thing that had to be beat in to my head was their avoidance of hardwood cabinetry or large area of real wood trim.

This is again due to the huge temperature variations and humidity suffered by bus interiors.  Just like your car in summer, you can take it from 150+ to 70 in about 15-20 minutes!  Not too many materials can survive that over time.  That's why so many high-end conversions use laminates for walls, cabinets and just about any large surface.

Personally, I dont care for the look of laminate cabinets and especially walls.  I prefer to use a luan or thin plywood base, putty up the seams, then coat it all with adhesive and cover with material.  I'm currently using a loose tweed material that after almost 14 months of harsh weather variance, has held up beautifully.  I did have to re-adhere a few ends, but that was due to operator error when installing :-)

HTH, here's a pic...

[cody]

I guess again I'm the odd man out on this but I'm a great fan of hardwood in homes and buses, I also have called a lot of high end converters friends over the years and the biggest reason a lot use laminates is the cost factor, one from marathon says laminates cover a broad range of sins and mistakes and still be marketable lol. My grandfather was a master cabinetmaker, as was my father, I don't call myself a cabinetmaker but I've been makeing sawdust for about 40 years now and I've found that hardwood still is very stable in a bus if done properly, joints don't have to open up and with a good fit there shouldn't be any need for a filler. The biggest problem I see with many conversions is the industries need to rely on cheaper grades of material and depending on pneumatics to fasten.  I realize that once again it boils down to cost and getting the product out but to me it cheapens it, sure it's pretty and it sells but I just have a hard time finding old world craftmanship in it. When I see cabinet grade plywood, for the most part I see standard plywood with a veneer, not lumber core plywood, there is a big differance in the stability found between a "cabinet" grade plywood with a fiber or bark series of plys and a true cabinet grade plywood with a lumber core, but that difference involves a hefty price difference too, one that most converters are unwilling or unable to pay.  True cabinet grade plywood offers a solid interior to anchor the hardwood front too and will create a very stable platform to work from where the lesser varieties will almost always cause problems down the road. A hardwood front thats properly dadoed into a quality framework will very rarely open up or create any problems, even with the movement or temperature variations of a bus, but like I said if the casework is of poor quality, the end result won't be as good as it could be. Before I get flamed, this is just my opinion and just my experience for what thats worth.

[Stan]

For those who want to use 'wallpaper' spend the money and buy commercial wall covering. The material used in hotel corridors and restaurant walls is a vinyl  coated cloth that resists tearing and cracking. It requires a different method of application and a different glue than the paper wall covering. You will likely have to special order it from a paint and wall covering store.

[David Anderson]

That is a good point, Stan.  I wish I would have known more 6 years ago when I put the wallpaper in the coach.  As I stated in the thread farther up the board, the thick wallpaper I put in my galley was almost similar to a vinyl table covering you might see at your favorite cafe or coffee shop.  I bought it at Home Depot and haven't seen any like it since. 

The point is the covering has to be able to stretch a bit and hide behind some sort of edge trim at all its ends.   Though it is just my opinion this is probably true for any type sheathing substrate in a motorhome application.   There is just too much movement.  It's like a constant earthquake. 

David

[FloridaCliff]

While were talking about walls!

Nick turned me on to the idea of using body filler on the joints, worked perfect. 

Cliff

Nick and Cliff,

I used wallboard compound to cover the joints in my sheathing.  It covered them very well, but after about 4 years every joint cracked from bus contracting/expanding.  This played havoc with the wallpaper my wife liked so much.  I had to remove all the paper and glue up carpet.  I'm thankful I painted the plywood with Kilz before installation or that paper removal would have been awful.

However, in the kitchen we had originally installed a very thick vinyl paper that simulates ceramic tile and it has held up well.  Only if you look really closely you will be able to see the sheathing crack. 

I feel like body filler would have had similar results over time unless it can flex with the bus.

David

David,

So far I have not seen any cracking, anywhere.

I used it to fill the minor joints between the sheets of plywood and to cover the screws.

Cliff

[coachconverter]

Regarding Commercial Wallpaper,

Probably stating the obvious, but if you pick a non-directional pattern you can get 6-8 foot wide rolls and run it lengthwise for no seams.  Just be prepared for the cost, or find odd-lots.  Plenty on eBay usually.

HTH

Todd