linuxmanxxx wrote:Reread what I said about underlayment and not finish. If it is used for a base that then has a waterproof agent and then covered by another physical substrate (aluminum, frp, or canvas) and then sealed it will last many years. If you leave it exposed to the environment with only paint or some other liquid based coating it will delaminate because of the properties of what it was built for. Think about it as there are zero houses built with exposed plywood and they are covered with tar paper and then shingles and the plywood doesn't rot. There is wood siding or cedar siding on the sides but vertical weather properties are nowhere near as harsh as the more horizontal portions due to both UV and water access to them. Any wood exteriored TD requires lots of chemicals to protect it as well as high quality wood and to me not worth the trouble in the long run but we all have our preferences. I like aluminum as its UV tolerant, waterproof, light, and won't breakdown under the elements and if glued correctly won't have any oil canning or visual defects.
Zero houses built with exposed plywood.. How so?? Ever heard of Texture 111. It's just grooved plywood with the inner layers actually exposed. It is/was used extensively as a sheathing/siding material for cheap houses and garages. There is lots of it around here. Most of it is just stained, not painted or any other exotic coating, just grooved exterior plywood.
The question is whether Russian Birch is Exterior or interior plywood? I was told the RB ply I bought was interior. If you do a search for the difference, you will find the interior glues are intended for no moisture low humidity environments. IMO/ an aluminum wrapped TD trailer is the same as a tin can. There is indeed high humidity going on inside a closed TD from occupants respiration. This moisture will eventually get to both interior and exterior 1/8" ply roof, and maybe wall skins. ventilation from windows and roof vents helps, but it won't expel all moisture. The question is will the interior plywood hold up to the humidity? You won't know it's happening because it's hidden under that nice shiny aluminum skin. Maybe when you smell the mold....
I don't know how aluminum can not oil can. It expands and contracts a lot with temperature changes. The large flat sheets must move, especially since the edges are fastened tightly with screws, unless the screw holes are over size? I don't see how gluing it will stop the expansion/contraction movement. I have seen several members mention that it does ripple and move, but contracts flat when cool, it's just the nature of sheet aluminum that one has to live with.
I actually like aluminum for a TD, but I would need to know no moisture is getting in, or worse, not getting out..
Posted: Sat Mar 03, 2012 5:23 pm
Danny
