Aluminum for underside?

[vegask]

Trying to figure out what I am going to use to build my floors and water proof them. Was wondering why people do not use a sheet of aluminum (0.03 or similar) to the under side of their floor instead of using roofing tar and other sealing methods? Or have people done this and I am just not looking hard enough?

[dales133]

Im using aluminum for the sub floor of my build.
1.6mm sheet for tbe rear under the draws and 2.5mm tread plate for tbe front section.
Light,dosnt rust and waterproof

[noseoil]

Cost & availability are most likely the two main factors. Most people don't have a sheet laying around to use for a bottom skin. Cost is another factor.

Asphalt is cheap, foolproof & available everywhere. Once it's in place & dry, the asphalt will outlast the build. Since it's not subject to any UV degradation, it just lasts a long time. All it needs to do is provide a moisture barrier & the occasional shed mud, snow & slush from travel in sloppy conditions.

I also looked at HDPE sheets (white milk jug plastic sheet material, .063" X 60" X 120") which was cheap & also completely bulletproof for a trailer floor, but didn't have a local distributor to buy from. I went with 2 coats of polyurethane & some white roof coat.

Why throw money away if you don't need to?

[alaska teardrop]

Trying to figure out what I am going to use to build my floors and water proof them. Was wondering why people do not use a sheet of aluminum (0.03 or similar) to the under side of their floor instead of using roofing tar and other sealing methods? Or have people done this and I am just not looking hard enough?

I use aluminum attached to the steel frame (.050" minimum) overlaid with extruded polystyrene & a thin flooring. No wood flooring structure or tar. Some pictures & more information here: viewtopic.php?f=27&t=51991