The Floor.

[One Awesome Inch]

I am trying to decide which direction to go with regarding the floor. Naturally I want as much headroom as possible and the more I insulate the ceiling (more important than the floor) and the floor, the less headroom.

So what should I do with the floor? 1 inch thick plywood on top of 1 inch polysio foamboard? Then put some linoleum on top. Or maybe 1/2 inch plywood to gain more headroom? Bob has said its virtually impossible to keep the floor warm so why give up the headroom?

Ideas?

 

[cdiggy]

Been debating this myself. My body is all aluminum so it absorbs heat and radiates it to wherever I don't want it to go. I was thinking closed cell spray foam for underneath and either a cork or foam underlayment and an engineered cheap wood floor over top. I am looking for answers too!

 

[Seraphim]

http://www.buildgp.com/DocumentViewer.aspx?repository=BP&elementid=4284

I've used this under tile floors and walls, and always wondered how it would work in a van floor. Not sure of its insulation value, but you score it with a razor and break it along the score. Screw down with sheet metal screws. Expensive, though...

 

[Almost There]

http://www.buildgp.com/DocumentViewer.aspx?repository=BP&elementid=4284

I've used this under tile floors and walls, and always wondered how it would work in a van floor. Not sure of its insulation value, but you score it with a razor and break it along the score. Screw down with sheet metal screws. Expensive, though...

Insulation value is absolutely minimal. The chart shows it to have an insulation value of .56 (if I'm reading it right.) Heck I have socks with a higher R value...

The problem with insulating the floor is that even closed cell foam compresses under variable weight like walking on it. Short of building a shallow frame in a grid to support the plywood overlay and laying insulating material in between the grid structure, it's difficult to get anything under there. With the cost of building the grid, laying ccf and the loss of ceiling height, I wonder how much it will help.

A nice fluffy area rug, some warm insulated socks and using a footstool to keep my feet up off the floor will go a whole lot further to keeping my feet warm IMO.

 

[Seraphim]

Insulation value is absolutely minimal. The chart shows it to have an insulation value of .56 (if I'm reading it right.) Heck I have socks with a higher R value...

The problem with insulating the floor is that even closed cell foam compresses under variable weight like walking on it. Short of building a shallow frame in a grid to support the plywood overlay and laying insulating material in between the grid structure, it's difficult to get anything under there. With the cost of building the grid, laying ccf and the loss of ceiling height, I wonder how much it will help.

A nice fluffy area rug, some warm insulated socks and using a footstool to keep my feet up off the floor will go a whole lot further to keeping my feet warm IMO.

Thanks. I looked for the R value, but didn't see it. Older eyes...

 

[MrNoodly]

What does your van have now? Just the bare floor? If so, put down some 1/4" plywood and, if you want to get fancy, some vinyl flooring or cheap rugs, then call it a day. It's way easier to insulate your feet with these things called "shoes" or "slippers."

 

[akrvbob]

Let's imagine a scenerio. It's 25 degrees outside so you turn your Mr Buddy on to warm up. In an hour the inch of air at your ceiling will be 110 degrees, where you are sitting will be 90 and the floor will be 35.

Insulating the ceiling is critical because that's where the heat is, the walls are important because there is also lots of heat there, the floor is unimportant because it has no heat. A 10 degree heat difference between inside and out is almost meaningless as far as heat loss. But the 85 degree difference at the roof is critical because without insulation all that heat will pour out of the sheet-metal.

The only time insulating the floor pays off is if you devise a fan system to pull the heat off the roof to the floor. That wouldn't be hard with some PVC pipe and a computer fan.

I just put down throw rugs in the traffic areas so my feet don't touch a cold surface.
Bob

 

[MikeRuth]

guess I should add what I did. 7 years ago when I bought my van it was for work. Computer repair and I had no intentions of using it as a camper or vandwelling. So I laid in from firewall to rear door, Reflectix on the metal, 3/4" composite wood from behind the seats to the rear doors and screwed that down, then laid in 1/2 inch composite foam and lastly indoor/outdoor black carpet. Yes it took up about an inch but I didn't care. I wanted one thing more than insulation and that was to be able to crawl around on my knees and not feel those damn ribs. I actually have a little cush.

I've read here where folks have said that no matter what they do the floor it still gets cold. Well mine doesn't! and it doesn't get hot. Now with that said, I'm not talking the ultimate insulation here, but when I laid down on it and it was 110 outside it wasn't bad and likewise when it was 30 outside. I know, I haven't tried it when it -20 but I don't think I will have too at least I hope not.

So take it for what that's worth.

Mike R

 

[Luisafernandes]

If you see my build, I used Polyisio (forgot what thickness), on top of that I used 1/4 underfloor material, and 1/2 (I believe) laminated floor. I didn't fill in the floor ridges. I placed the Polyisio right over it leaving the lower ridges uncovered. If by any chance water or any other liquid gets in there all I need to do is park uphill and let the liquid(s) drain out. [emoji106][emoji4]

 

[cdiggy]

My problem is 1/4 diamond plate aluminum. It just conducts heat so well that when then truck is running the floor gets HOT. It is also freezing cold when the temp drops. But it doesn't rust. So I've got that going for me. Which is good

 

[karl]

I agree it's a waste of money and headroom to spend lots on floor insulation, I do think that a thermal break between the metal and finish flooring is a good idea though.
I've used the fanfold insulation commonly used under vinyl siding, or high density foam carpet pad under the floating flooring and throw rugs with good results.
Thirsty (step van) was tall enough so that I used 1 1/2'' thick foam back commercial carpet (it is used in play, exercise areas, safe rooms)that I scored from a remodel project , then laid floating floor over that and throw rugs. It made a noticeable difference in the heat and cold conduction as well as noise level.

 

[MrNoodly]

Of course, if you have shore power, you could do electric in-floor radiant heating.

 

[LeeRevell]

Of course, if you have shore power, you could do electric in-floor radiant heating.

I have seen a couple RV owners do this over on IRV2 forum. Of course, they have a LOT more disposable income than most of us, and much bigger 'homes'!

 

[concretebox]

One-inch thick plywood seems overkill, and heavy! My Class B came with 1/4 inch plywood screwed directly to the bare metal floor. I put laminate planks over that and two floor rugs down. The rugs are nice a warm and floor is pretty cold.

 

[LucyImHome]

My 91 Allegro MH had spray foam sprayed ALL underneath, thick. Even the gas tank! Not fun when it had to be dropped to replace the fuel pump. But, the floor was never cold. I don't know if this relates in any way to a van, just thought I'd throw it out there.

 

[cdiggy]

My 91 Allegro MH had spray foam sprayed ALL underneath, thick. Even the gas tank! Not fun when it had to be dropped to replace the fuel pump. But, the floor was never cold. I don't know if this relates in any way to a van, just thought I'd throw it out there.

Yup. That is the drawback of spraying the undercarriage. Lots of stuff under there. Still might give it a spray if I can keep it off the important stuff though.

 

[masterplumber]

On my cargo trailer conversion I just have the original 3/4'' plywood floor with no insulation. I laid down 1/2'' felt carpet padding and some indoor outdoor carpet that feels softer than most, but it's not really any plusher. It was 15 degrees outside this morning and the floor felt cool in socks, but not cold. I have it wall to wall, but loose, not tacked down, so I can pull it out to clean. It seems to be working well. I thought of the idea from winter pack boots which use felt for insulation in the insoles. Fortunately my carpet supplier at work had the felt padding available and I think I spent about $120 for both it and the carpet for a 6 x 12 trailer, which is about the same size as a van. If I was to do a van I would probably put down 3/8'' or 1/2'' plywood first. I think 1/4'' is fine if you have a hard surface over it, like laminate flooring, but I think it would give to much between the ribs with just carpet. Just food for thought as there are a lot of great ideas out there with varying degrees of success. I know one guy who lives in the mountain states and who reported good success with those interlocking foam tiles like you use in workshops and play areas for padding. You just have to have throw rugs where you walk so you don't put holes in them from rocks in your shoes or what not.

 

[LeeRevell]

A lot of folks on Youtube doing their van builds first put thin laths of wood in the lows between floor ribs, then the plywood over that doesn't have to be very thick. No sagging. Then lay on the insulation and final floor covering of your choice.
Looking at my '88 E150 Conversion Van, they put a 1/2" layer of OSB on the floor, then 1/4" of soft open-cell foam on the OSB followed by a fairly stout indoor/outdoor carpet. The carpet is dark brown and doesn't show dirt too badly, but is cut up some where they removed the #4 seat. I need to replace the #2 seat (doesn't swivel and has no arms) with the better condition #3 seat (it swivels and has both arms) , so will likely have to cut the carpet more to get them out. And again maybe when removing the rear bench seat. So I may be replacing that carpet completely. That'll allow me to replace the thinner foam with thicker Polyiso first. If the OSB is in good shape it will remain.

 

[ccbreder]

Head room is good, but I still remember camping at St Mary's Glacier and the pain from the cold floor. I put 1x2 popular stringers down the length. Being in two grooves it allowed 1/2 inch above the floor for 1/2 inch closed cell foil backed insulation between the two stringers (R 3.1). Bolted through plywood over that. This served to protect the foam. I could have used 1/2 or even 1/4. I used 3/4 because it will be used to anchor fixtures screwed down in the van. I also lowered the center of gravity with the weight of the ply. When finished I will post photos and also comment on my new head room.

 

[FortWorthVanNoob]

I don't know what's best but what I did was put down 1 inch polyiso, 1/2 inch plywood, carpet padding and then carpet. Cost about $200 from Lowes. The hardest part was cutting the plywood the correct size. It took two sheets of plywood, two polyiso sheets, 12 feet of carpet and padding, about 20 screws and nuts, 2 packages of tack boards, 5 razor blades and some caulking for underneath the van. (I only did the cargo area)