Attaching Foam Side walls to deck ?

[Just Mike]

I am contemplating building 2 inch foam. I have watched endless YouTube build videos and have yet to see one that makes a decent explanation of how to attach foam sidewalls to the floor. Anyone have successful experience in accomplishing this?
Any ideas or experience would be greatly appreciated.

[TimC]

Are you doing PMF? Canvas and paint covering the exterior? I'm about to do that step today! I've attached some pix. I will update those as I glue up the walls this afternoon.

Halfway down on page one of my Build #3 - Foamie journal (signature line link) I show how I did that wall attachment. The void in the bottom edge of the 2" rigid foam is made using a hot wire. Or in my case a soldering gun with a homemade 14 ga copper wire in the shape needed to melt the path on the edge.

I'm anchoring the wall different this time. On my son's build we glued the cleat into the wall void and then glued and screwed it secure from under the floor. On my current build I attached a cleat to the floor (1x2), glued and screwed it then I'll put the wall over that with PLPremium as the adhesive and the canvas flap will be glued to the floor base and underneath it with Titebond II wood glue. Then the paint job will protect that layer of canvas. Drip edge will be added to eliminate standing water. Interior wall also has a flap of bedsheet that I'll anchor to the interior floor. I credit my method to ghcoe!

Check out George Coe's posts (ghcoe) and Glen's posts (GPW). Two experienced builders who I credit most of my knowledge to.

My cleat...


Dry fit of wall...

[TimC]

The photo down a bit in this post is a shot of the brace I make for standing the walls up. The brace holds the front, mid-point and galley end of the walls plumb while the glue (PLP) is setting on the floor attachment point. A simple set of braces will assure your foam doesn't need to be stressed after the glue dries as you pull the walls plumb for roof work.

Wall to floor seam exterior. I tape the canvas flaps up to keep them from getting in the way while I glue and anchor the wall. Then they will be glued down after the glue sets.


And wall to floor seam interior.


Better photos of the braces I use to keep the walls plumb. I have three across the top and one more in the window to door space to pull the wall straight.






And finally, the walls were skewed to the road side about a quarter of an inch so I rigged up a rope anchored by my wife's car to keep it straight while the glue sets. It will spring back so I will be putting in a square brace later before I start the headliner and roof materials. I made a brace to hold the wall straight even though the window frame will hold it straight. I want the window frame to mate with a straight wall for obvious reasons. As PMF dries it will pull the wall in different directions. Not a nightmare to remedy but you should watch for and adapt for that.

[Just Mike]

Thank you for your pix and reply. Foam is the best option because our unit
Needs to be about 1000 lbs dry max. Like I said we are still in the
Thinking stages.