TIL: People Build Camping Trailers From Rigid Foam Insulation

I don't mean they insulate their trailer with it, I mean they BUILD the trailer with it! I've been running down this rabbit hole all day. I'm fascinated.



There's even a forum:
https://www.tnttt.com/viewforum.php?f=55
 

They drape the foam panels with canvas then soak it in epoxy to make what they call "poor man's fiberglass" to strengthen it. Genius!

I have a 5x8 utility trailer that I've been noodling on how to use it for camping somehow other than just hauling our stuff in it. I keep thinking about a removable camping insert "pod" that I can put on the trailer whenever it is camping time. I'm not a woodworker by any means, but a foam pod could be a solution, albeit likely an ugly one.

These folks built a wooden "camper pod" on skids that seems like a good solution that could be adapted to foam construction:
 

I've seen some of that in the past, and the part that really confuses me is the use of "poor man's fiberglass".

One sheet of that pink foam is ~$30, and I can't really see doing that with less than 4 boards.  But 4 would be $120.

Getting what seems to be the proper fiberglass and resin would be ~$100 more.  Doing the cheap glue/canvas is only about 1/2 of that. 

Call it $250 in materials vs. $190 to be generous in those materials.  

So why not do it right?  A proper FB system would add a considerable amount of structure- since this is being built like a boat.

One other thing I would want to know before I traveled this journey (which I've considered) are the RV build requirements that Curtis has brought up in other threads.  

I wonder how durable they really are, but I can see the benefits of light weight and the insulative properties.

Before we got the RV & I was still planning to raise the roof on the van, I was going to use this method. Although I was going to build a 1" square 16ga frame to help reduce flex. 

This futuristic aircraft is foam core covered in fiberglass.

The design's been around for 47 years.

How long does it take for the foam and epoxy to "gas out "

Isn't this just a really thick wing?  Of course having the trailer airborne might reduce the fuel used...

Just don't flip it on the highway...

In reply to bearmtnmartin (Forum Supporter) :

Well, that goes for most any camper...

The zinger here is that you cannot use much cheaper polyester resin, as it melts the foam before cure. Epoxy isn't cheap. There needs to be about two gallons of epoxy soaked into what ever cloth used. That is over $400. for the good stuff. 

on the flip side, you can buy marine epoxy by the gallon.  Just do not get it on your skin, you will develop an allergy with repeated exposure.

In reply to Appleseed :

there is that, too.  

My dad has built 2 with this method. Foam, canvas with wood glue for the exterior and paint. Floors are super light, frame made of 2x2 with foam between and 1/4" thick plywood skins. He builds the boxes then bolts to a trailer. One was an old popup frame and one was a boat trailer frame. they tow well because they weigh nothing and have done fine sitting in his yard when not in use. 

I am a member on that forum, and I have built a couple campers.  They call them foamies. In my state these are not considered rvs, they are just a trailer.

Appleseed said:

This futuristic aircraft is foam core covered in fiberglass.

The design's been around for 47 years.

Weeelllllll, it's a bit different.  The foam is an open cell, urethane, PVC or other material that doesn't react to common resins used with fiberglass.  The glass is also several layers thick and, with the resin, is the actual strength of the structure.  These campers use the foam as the strength and the covering as protection.

In reply to alfadriver :

You're going to want to insulate the fiberglass camper too so count that in your materials costs for both. 

Appleseed said:

This futuristic aircraft is foam core covered in fiberglass.

The design's been around for 47 years.

My college job was working in a big box store. Every week or so a guy would come in and buy all of the 2" thick rigid foam that he could fit into his van. I eventually asked about his project, and he told me "I'm building a plane." Not sure I want any part of a home built foam aircraft, but it kind of makes sense. He eventually stopped coming in. I choose to believe that he's too busy jetsetting around the planet and not that he met his demise.

Don't fall asleep with a cigarette on your night stand. 

How long does it take for the foam and epoxy to "gas out "

I was under the impression that PMF was cloth/canvas and watered down wood glue.

Using epoxy would take the poor out of PMF

My buddy built one out of plywood and it slides in and out of his 4X8 utility trailer, freeing up the trailer for other uses when he's not camping.

dculberson said:

In reply to alfadriver :

You're going to want to insulate the fiberglass camper too so count that in your materials costs for both. 

Why add more?  That amount of foam is more than enough to insulate a camper just in the build.  More than most campers.

In reply to alfadriver :

Sorry, I think I was confused. I thought you weren't counting the foam board costs in the fiberglass alternative.

Peabody said:

How long does it take for the foam and epoxy to "gas out "

I was under the impression that PMF was cloth/canvas and watered down wood glue.

Using epoxy would take the poor out of PMF

My buddy built one out of plywood and it slides in and out of his 4X8 utility trailer, freeing up the trailer for other uses when he's not camping.

That's what I want to do! Any chances of asking your buddy for a pic?

My 5x8 is currently set up with sides for vacation mode hauling, but also for cargo.

For vacation mode I have a fitted tarp that I pretty much "gift wrap" the trailer with and haul all our luggage/bikes/food.

Our mighty steed is a 2017 Sedona with a tow capacity of #3,500. I'd guess that I've never put more than #2,000 behind it, but it tows great.

I was thinking a slide-in "squaredrop" build with this shape:

I'd have to make some decisions on door placement in regards to the current high sides. Maybe make a U-shaped door in the existing sides to allow for camper doors.

Right now it is all theoretical anyway. I still have to sell my '75 Duster, replace the heater pipes on my E46, and get my '69 Olds running again. Building a camper is somewhere down the list...but I do happen to already have a stash of leftover rigid foam from insulating my garage office....

Is the foam structurally sound enough to make a home made clamshell that hinges open for snowmobiles?

Im thinking it could be used for summer storage if I included a floor to make it removable like some of the camper concepts. Essentially a foam storage container. 
 

In reply to triumph7 :

My point was more of if Rutan can build safe aircraft out of foam and fiberglass, we can certainly build a camper out of it.