too light walls?

[Greg Barrick]

OK. Another question I've had since building my 4x8. Would a wall be strong enough using 1/8" luan inside & out with 1x2 or 1x3 vertical wall studs? Also being filled with rigid foam for insulation? (Particulary on a 6-1/2' x 12' x 4' high wall.) This would allow standard finish roof trim screws to "bite" into wood instead of the end of plywood. I used 3/8 ply external, 1/8 luan and 1x2 studs on my cubby and it seems plenty strong. Is 3/8" or more plywood REALLY important?

[Forrest747]

If i read it right you are looking at 1/4 inch total luan for teh inside and outside. you looking at about 700 to 750 pounds of force. that should be enough with the rigid interior bracing. so no more than two adults sleeping on the roof at a time

[Miriam C.]

It's a box. If you frame it right it will be fine. Mine had a 1/8" roof and it survived a tornado. Only had some dents and dings...You will be fine. I do suggest for those who are able to use marine epoxy to coat the roof. Amazing stuff!

[linuxmanxxx]

I've built 3 using the 5mm luan and 1 x 2 framing and even took one of them down to minimal framing in the walls and can walk on the roof at almost 200 pounds.

Its all in if you get the luan to bond to your foam correctly. I introduced using 3M 30NF water based contact adhesive on here and now several have used it with stellar results. It's pricey but well worth the money in the finish and performance it provides. I've cored my floor to put some vents in and I cannot separate the luan and the foam without destroying the foam so it sticks ultra well. If your thrifty with the glue you can do a 5 x 8 roughly with around a gallon but if you double skin the outer walls it will take another half gallon to do it and it runs around 150 a gallon. It covers way better than the weldwood contact cement and its not toxic and won't eat the foam like a solvent based glue.

[angib]

I don't believe you can build a teardrop sidewall that isn't strong enough to support the rest of the body. However what 1/8" skins will lack is 'puncture resistance' - things like stones could damage 1/8" where most wouldn't touch 3/8".

But then plenty of folks have 1/8" roof skins and they take the much worse punishment from stones on the front of the trailer. I'd be inclined to think the one place that more than 1/8" is needed, for local durability not overall strength, is the bottom half of the front of the body.