Perfect floor?

[sjacobso76]

I've looked but can't find anything recently on this.

I'm building (this Winter) a 5X10 TD. I'd like it to have an insulated floor, and I'm wondering on opinions to the best way to build it. I'm thinking of using baltic birch since it comes in 5X5 sheets. So, would 1/2" skins with ? in between be appropriate? How thick should that space between the floor skins be?

Oh, I'd also like to put a storage space into the floor. Shouldn't change anything, but I thought I'd throw it in there.

Thanks! I promise I'll start contributing when I have something to contribute!:)

[RichAFix]

My floor is a sandwich type construction:
.25" birch plywood/.75" poplar framing with pink .75" insulation/.25" birch plywood.

I don't know what kind of frame you have underneath it, but this is very strong, no flex at all and the poplar gives me a good screw hold for when the sides are attached. I tend to overdo things so my sides are also glued into a dado the length of the trailer. That dado also keeps the floor straight.

[aggie79]

My floor is a sandwich type construction:
.25" birch plywood/.75" poplar framing with pink .75" insulation/.25" birch plywood.

I don't know what kind of frame you have underneath it, but this is very strong, no flex at all and the poplar gives me a good screw hold for when the sides are attached. I tend to overdo things so my sides are also glued into a dado the length of the trailer. That dado also keeps the floor straight.

I built my floor the same way as Rich. In the cabin part of the frame, I don't have any steel crossmembers, and, even without these, there is no flex in the floor.


Gig'em, Tom

[sjacobso76]

Thanks guys! So do you put the cross members at 16" on center? Also, do you think the footwell storage type thing would weaken this at all? I would think that could have an effect as the sandwich seems like it acts as a torsion box to keep everything rigid. Taking something out of that might have a negative effect. I will have cross members, so maybe that point is moot.

Is 3/4" enough insulation? It doesn't seem like much to me, but I really don't know anything about trailers. Does anyone use High-R value insulation (the foil faced stuff) to get more R value in there?

Sorry for all of my questions; I'm the kind of guy that becomes interested in something he knows absolutely nothing about, and then researches the heck out of it before starting. I am really excited to build this thing!

[Arne]

I used 1.5" foam, with 3/8" on top and 1/8" on the bottom. I put heavier wood where I would need it (like to attach galley wall... where I did not need it, I used 1/2" ply stringers set on edge, 1.5" tall..

So, you can see there are lots of ways to do this. I have a perimeter frame, but no x members. I also have no flex.

Going to 1.5" adds little to the weight and makes sure the floor will not be cold and cause condensation. The insul is pink foam. One thing that did happen was the 1.5 insul may be a bit oversize in thickness. This caused the bottom 1/8" to bulge a little. Never caused a problem as everything is glued and nailed, so it isn't going any where.

you can see some of it if you go to the link below, the opening page.

[Juneaudave]

While I insulated the floor of my last build, a lot of folks would say you don't need insulation in the floor...the foam mattress is enough, or, they put the insulation inside loose and the mattress on top. By doing it that way, you don't create a trap for moisture between two layers of ply. I sure can't tell you which is right...

[Rock]

How about no frame at all:



1/4" luan, 1.5" framing lumber, 1/4" luan, blue board insulated, glued with thickened epoxy, fiberglass cloth and epoxy top and bottom.



This floor is flat within 1/16" and very rigid.

Eric

[sjacobso76]

So if you don't put insulation into the floor, would you still build a torsion box for the floor? It makes sense that it would be the lightest way to create a very strong floor.

[Rock]

Depends. If you're using a full framed trailer with a flat floor and aren't concerned about insulation, then a 1/2" piece of plywood thrown on there is probably sufficient. (If you look at my floor, it cost me dearly in terms of $ and hours, but I don't have a frame.) But then you have to mount your walls to something. The trailer frame in this case I guess.

You could then mount your under floor storage boxes to your cross pieces and the thin-ness of the floor isn't a concern.

As someone said, there's as many ways to build them as there are people building them. Your best best is to read everything possible here and elsewhere, and find what has worked for someone else that will also work for you.

Everyone has different needs/wants/abilities/limitations. As Hodder says "Build what you want. Enjoy what you build."

[alffink]

Insulation - No Insulation - always a hot button issue, but I looked at it this way, the rigid foam weighs next to nothing and nearly as inexspensive, to insure that the floor, walls and cieling does not form condensation where using the mattress as the insulation, may insulate you but does nothing to protect the interior of your tear. Just be sure to concentrate on sealing the floor and walls, etcetera. You'd best be sure it's sealed, even if going without the foam.

But, to each his own, weigh the pros and cons and decide for yourself, based on what you want, for the areas that you will be camping in.

[aggie79]

Thanks guys! So do you put the cross members at 16" on center?! Also, do you think the footwell storage type thing would weaken this at all? I would think that could have an effect as the sandwich seems like it acts as a torsion box to keep everything rigid.

I put the crossmembers at 16" o.c. except where my galley bulkhead and front cabinet face frame intersected the floor. I made sure there were crossmembers there so I could fasten them to the floor and increase the structural rigidity.

Is 3/4" enough insulation? It doesn't seem like much to me, but I really don't know anything about trailers. Does anyone use High-R value insulation (the foil faced stuff) to get more R value in there?

The foil facing doesn't actually add any R-value. It could reflect radiant heat. You'll find sometimes that the "blue" or "pink" insulation runs thicker than the beaded "white" insulation. I used the white to keep from having to trim/sand the blue or pink.

I'm in the group that says you should insulate, especially if you camp in temperature extremes (above 80 degrees or below 40 degrees) and you try to cool/heat the interior of your teardrop.

[caseydog]

So if you don't put insulation into the floor, would you still build a torsion box for the floor? It makes sense that it would be the lightest way to create a very strong floor.

If your metal trailer frame is rigid enough, there is no need for another frame on top of it -- which just adds more weight. I've heard a lot of folks on this forum say they overbuilt their first tear.

I put a sheet of 3/4 Birch right on top of my frame.

I do like the idea of the sandwich of foam and plywood to insulate, assuming it gives enough R-Value to be worth the work and money. It should, however, be lightweight and strong.

Another option is to use a radiant barrier on your plywood floor.

No mater what you do for the floor, and good foam mattress should be plenty of insulation beneath you. Just don't try to use an air-bed if you camp in freezing weather -- even with insulation.

CD

[kennyrayandersen]

Insulation - No Insulation - always a hot button issue, but I looked at it this way, the rigid foam weighs next to nothing and nearly as inexspensive, to insure that the floor, walls and cieling does not form condensation where using the mattress as the insulation, may insulate you but does nothing to protect the interior of your tear. Just be sure to concentrate on sealing the floor and walls, etcetera. You'd best be sure it's sealed, even if going without the foam.

But, to each his own, weigh the pros and cons and decide for yourself, based on what you want, for the areas that you will be camping in.

Not only that, but there is no down side (OK, maybe it potentially costs a little more). It’s lighter, stronger, AND insulated. Sandwich construction, structurally speaking, is the end of the road. Basically these are all home-brew copies of how we build in the aerospace world (just the materials are a little less high-tech for the home builder). The insulation is just a free bonus.

[LMarsh]

Just another thing to consider, we live in NY and camp 6-7 months out of the year and I've never been cold in our tear. Actually I'm usually uncomfortably warm. Even with a fan going or 50 degrees outside we're nice and cozy with just a blanket and the windows cracked to let moisture out. My floor and walls are not insulated, just the ceiling. I will never skimp on a roof vent fan again though because getting air to properly circulate has been a problem. Needless to say I'm a warm sleeper though, especially after those Rochester NY garbage plates! Lots of fuel in them.

Lucas

[chorizon]

Needless to say I'm a warm sleeper though, especially after those Rochester NY garbage plates! Lots of fuel in them.
Lucas

??????

I had to google that, and it looks awesome. Why hasn't the Man Vs. Food guy gone to Rochester? Josh hungry now, must eat...