How'd you insulate the floor?

[Oak]

How did you all insulate your floors? I plan on sandwiching insulation between sheets of ply (size undetermined yet) and would like to see some pictures of how some of you did it. Thanks!

[Oak]

And by the way, I searched...couldn't find any info. I'm not just lazy..

[Juneaudave]

1 x 2 fir framing, 3/8 inch top ply, 1/4 ply inch bottom, 1 inch Foamular insulation...

[Boodro]

Oak , I layed my mattress on the floor , its 6 inches thick & covers the whole floor. Is it REALLY needed to build a samich floor with insulation??? I did not see the need or the expense being worth it. My floor is 1 inch ply.

Just my 2 sense worth!! Good luck!

[Arne]

Depending on how you build the floor, sandwich can be the same weight as solid ply.... or lighter.. This floor is the equiv of 1/2"... 3/8 top, 1/8 bottom, 1.5 inches insul... It is lighter than 3/4" ply floor.

http://www.freewebs.com/aero-1

[steve wolverton]

Insulation? Meh.

Foam mattress for most tears is plenty.

[Bodyman]

Depends on your use of a TD? Indiana? Be safe. Insulate your floor!!
Randy

[doug hodder]

I'm with Steve and Boodro....I think the R value you get out of the foam is going to be plenty....but if you choose to insulate, just make sure you get it sealed up really well....what a great place for water to work itself into and do it's thing, easy for it to get in....hard to get it out.....just my opinion however...Doug

[Oak]

I want to be able to use this as an all weather rec. vehicle. If I do insulate it, and I get it sealed up good, but water over time seeps in through condensation or whatever, how hard is a fix up? I imagine it might be a royal pain to have to replace a floor. It will be used in all climates and all environments, so, o.k., I need to figure out which will be the warmest, coolest, and driest method of floor.
How about this? I do just like Juneaudave but I also seal all lumber for framing the floor with some kind of water seal, I seal the ply too, then I put it all together, coat with polyurethane, then cover it with a coat of epoxy, then put the asphalt emulsion or tar on the underside.
Would that be solid or would I encounter problems? Would it be water/airtight?

[Juneaudave]

Say Oak...don't get these guys wrong...lot's of trailers have been built with framed/insulated floors and lot's more with a solid plywood floor. There are reasons for both...in your case, I think you are building 5 wide on a 4 foot trailer and framed construction may be more conducive for the overhang and to provide a good nailing surface to attach the sides..regardless...it's your trailer and your preference and either will work.

I think the point is...that if you go with a framed and insulated floor sandwiched with ply...just seal it real good. Looking at old trailers...water is definately the enemy over time. Epoxy is a good sealer, and should be used to coat the ply and then painted or black gooed or poly'd to provide UV and abrasion resistance. Don't put your epoxy over the poly. Epoxy always goes on as the first coat to the ply if you elect to use it.

Have fun with your build and keep asking questions!!!!

[Arne]

I agree pretty much about the foam..

I built my floor the way I did so I would not need steel cross members.. I wanted to get rid of the weight... since it built is like a hollow core core, and it had the space anyway, I put the insul in.. I used wood glue, so now the whole thing is like one solid block with no air gaps...

I wound up with a very rigid floor that weighed about the same as 3/4 ply.. and no steel x-members except one in front and one in back.

In places where I did not need a bolting surface, the 'joists' are just 1/2 ply set on edge.. where I might have to use bolts, I put 2x3s.