I know that most people are trying to build something light enough to work with their particular vehicle, but our MTVR has a 30,000-pound payload capacity, so there may be solutions that wouldn't work for other people, but would work just fine for us. Our MTVR's flatbed is rigid, and it's mounted to the frame with springs to make it torsion-free, so I'm not concerned about damaging the box from twisting off road.
We've explored the downsides to using an ISO container, and we've looked into using a dry van box as a basis...but what about building it out of wood, framed like a house, with plywood on the inside and outside, and everything glued and screwed. Flat-roofed.
This would give us total control over the dimensions that we're looking for, without having to modify something that was designed for another purpose.
This would give us something that is structurally strong enough to mount our 600-pound gun safe to, and strong enough to tie down a 400-pound motorcycle to. I have no idea how we would attempt that with FRP/foam SIPs.
This would make it easier/simpler to adapt certain design elements to, like our desire for a "drawbridge" type rear door/platform/ramp and rigid fold-down awnings to protect the windows against tree branches off road.
We would be able to build it ourselves, without any special tools or skills.
The materials could all be purchased locally from Home Depot at an advantageous pricing point, without having to pay to ship a giant stack of SIPs to us.
We wouldn't have to deal with thermal bridging of an aluminum or steel frame. Wood studs are still thermal bridges, but not nearly as bad as a metal frame. We could do the studs on 24" centers (instead of the standard 16" spacing) to reduce thermal bridging by a third.
We could make the walls, floor, and ceiling thicker, to allow for more insulation- we could do 5.5" of polyiso in the ceiling, and 3.5" in the walls and floor.
We could use off-the shelf insulated residential windows.
My biggest concern, would be how to keep water from getting into it. On the inside, we could use a vapor barrier, seal the seams, and seal the interior paneling itself with paint or epoxy or something. On the outside, I guess we could do the same thing.
What do you guys think?
We've explored the downsides to using an ISO container, and we've looked into using a dry van box as a basis...but what about building it out of wood, framed like a house, with plywood on the inside and outside, and everything glued and screwed. Flat-roofed.
This would give us total control over the dimensions that we're looking for, without having to modify something that was designed for another purpose.
This would give us something that is structurally strong enough to mount our 600-pound gun safe to, and strong enough to tie down a 400-pound motorcycle to. I have no idea how we would attempt that with FRP/foam SIPs.
This would make it easier/simpler to adapt certain design elements to, like our desire for a "drawbridge" type rear door/platform/ramp and rigid fold-down awnings to protect the windows against tree branches off road.
We would be able to build it ourselves, without any special tools or skills.
The materials could all be purchased locally from Home Depot at an advantageous pricing point, without having to pay to ship a giant stack of SIPs to us.
We wouldn't have to deal with thermal bridging of an aluminum or steel frame. Wood studs are still thermal bridges, but not nearly as bad as a metal frame. We could do the studs on 24" centers (instead of the standard 16" spacing) to reduce thermal bridging by a third.
We could make the walls, floor, and ceiling thicker, to allow for more insulation- we could do 5.5" of polyiso in the ceiling, and 3.5" in the walls and floor.
We could use off-the shelf insulated residential windows.
My biggest concern, would be how to keep water from getting into it. On the inside, we could use a vapor barrier, seal the seams, and seal the interior paneling itself with paint or epoxy or something. On the outside, I guess we could do the same thing.
What do you guys think?
Last edited: