Teardrops n Tiny Travel Trailers

Hello there - first post.

My intent is to have a 5'x8' with wood sides and aluminum roof.

I've checked the wall-to-floor attachment options from this thread: http://tnttt.com/viewtopic.php?f=21&t=19442
As aluminum sheets come 5' wide, it seems that the only option is to do a cleat. Because if I use any of the other attachment options, the total width will be slightly wider than 60", which means the 60" wide aluminum would have a gap on either side (I'm assuming the 5x8 trailer frames are exactly 5' wide - I haven't yet bought one - still figuring it all out before I proceed)

What I don't like about the cleat is that it seems to be vulnerable to water. And we have a lot of rain here in the Pacific Northwest.

I am wondering if a slight gap in the aluminum would be covered by the edge molding. If, for example, I used 1/4" exterior wall (1/4" + 3/4" bracing/insulation + 1/8" inner skin), could I let the 1/4" outer skin overlap the floor/frame (rabbet option) so that the water can run/drip away.

This would leave me with a 1/4" gap in the roof aluminum on either side - but would the corner trim (such as this: http://www.ebay.com/itm/RV-TEARDROP-TRA ... 1433253318) cover it sufficiently that it wouldn't be a problem?

That trim plus a liberal amount of sealant should stop you from having any problems. Nothing in my trailer is perfectly square so I had roof-to-wall gaps that I had to seal that way. I've sprayed them with a hose a few times and they don't leak.

I'd say I had a gap anywhere between 1/4" and 1/2" on each side. What I did was first paint the exposed wood with roofing tar. Let it dry. Followed up by smearing the whole thing with silicone. Then used more silicone to coat the bottom of the molding. Screwed it in place and wiped off most of the excess. I don't see any water getting past that.

My frame had a spot that was 60 1/2" wide, so the build was an "oversize" box to fit properly. I had exactly that same issue, but used 5' wide aluminum due to availability.

As Syberia said, the molding & adhesive (in my case butyl rubber tape) will cover a 1/4" gap, but make sure to seal the edges well with urethane or something to keep water out when you build. Also, each pilot hole should have a dab of sealant in it, prior to setting the screws. No leaks in ours this way & it seems to be holding up well enough so far.