Please help with front wall attachment at frame...

[MatBirch]

Hi gang, hoping for some insight here. I started with an existing frame. It’s a 70s camp trailer frame made by Ziemans in Oregon. The issue I’m trying to overcome, is the the tongue passes through cutouts in the front cross member, as opposed to welded under it. I need a good way to frame my front wall, skin and finish while keeping it waterproof, and prevent rotting.


I can notch around them, but it will leave the floor vulnerable. I can just caulk the crap out of under my skin?? Some sort of waterproof barrier like bituthane or bitumin ice dam preventer stuff over the floor and framing. Then line the lower section of the front wall in aluminum??
I can still pull the floor boards up at this point and wrap UNDER them??
The sides are easy. They will get a trim piece creating a lower cap and drip edge. The front corners where they transition to the front wall will look funny if I don’t drop the skin to the same level.


I build trailers at work, but we either have the tongue below the frame, or notch. But they’re all aluminum, so no rot risk.

Thanks for the help!

[Squigie]

Given enough time, I might be able to come up with a better idea. But what has come to mind as the best option in the last few minutes is:

Seal it.
Trim it.
Seal the trim.
Seal again when front wall is installed over-lapping the trim.
And seal again for good measure.

I wonder if butyl tape could be a viable option here...


(I am new here, for what it's worth.)

[MatBirch]

Given enough time, I might be able to come up with a better idea. But what has come to mind as the best option in the last few minutes is:

Seal it.
Trim it.
Seal the trim.
Seal again when front wall is installed over-lapping the trim.
And seal again for good measure.

I wonder if butyl tape could be a viable option here...


(I am new here, for what it's worth.)

Thanks

We have some stuff at work that’s like a foil HVAC tape with a butyl layer. I was kinda thinking about that stuff...

[MatBirch]

Well, here’s what I’ve come up with. Should work.
I used the butyl backed foil tape. It sticks like crazy!
I started by pulling up the front few inches of my floor and cleaning everything real well.
I cut a strip and slid it under the wood, butyl side up, so it is stuck to the wood on the underside, and wraps up the front edge. The tape is wide enough that it clears the frame underneath as well, so no water can get trapped between the frame and the plywood.


I then installed my 2x2 crossmember and screwed through all layers into the frame with Type F deck screws.
Next, I added another layer of tape covering the 2x, and overlapping the first layer. This left the seam in the tape “down”, so it can’t trap water.



I’m pleased with how it turned out.

[Squigie]

I hadn't thought about the type with a backing. I was thinking about the stuff that comes rolled in strips, but has no backing.

I've sealed a few RVs and other things with similar products. When applied correctly (and not over silicone), I've never had a problem.
It sealed my last motorhome so well that the water in the walls was then trapped and the rot accelerated. (I thought I had baked it long enough to be bone dry...)

[pchast]

I took 10" of canvas and glued half of it down to the bottom of the base
with epoxy before I bolted down to the trailer. The remainder was folded
over and glued to the foam side sealing the join before skinning.