is floor insulation really needed

[felixx]

Hi there
I am wondering, do I nearly need to insulate my floors?
I will be camping in New Zealand, rarely below -5 deg C and rarely above 30 deg C
I will have a 17mm ply floor with carpet and a 6" foam matteress.
Will I need an inch of foam laminated between 2 sheets of ply or is that overkill?

(I will have 17mm thick foam in the walls laminated between 1/4" ply (inside) and Laminated aluclad on the outside)
(nsulation in the roof will be one inch)
Cheers
Felixx

[grant whipp]

The simple answer is "No!"

Other's opinions can, and will, vary ... ...!

CHEERS!

[GuitarPhotog]

I concur with Grant. Your 5" thick mattress provides much more insulation than an inch of rigid insulation does.

<Chas>

[DezPrado]

Hi Felix,

Have to agree with Grant and Chas.
I have no formal insulation in the floor, only the walls and that is 18mm. Just 125mm foam mattress over 10mm foam camping mat on top of 18mm ply floor.
Spent a week winter bush camping out near Cheviot two years ago with the teardrop. One 7deg frost & four days of 'normal' frosts. Warm as toast sleeping with no additional or auxilliary heating, and no issues with condensation. (mind you I have been known to dig & use snow caves in the past, winter tent-camped atop Mt Kosciusko and Egmont, so warm as toast is relative to some, I guess)

[dales133]

I wouldn't bother in NZ the r
Temps art extreme enough.
I have here in aus but it gets alot hotter

[felixx]

Hi there
Thanks guys, thats saved a job!
Dez - Nice to see another south islander here.
Did I know you in Wanganui?

[MtnDon]

Needed? No. Maybe wanted or desired, maybe. Depends. Another matter of personal choice or preference.

[pigcooker]

Put some rigid foam board on the floor, under the mattress.
Made a huge difference in a pop up, can't hurt, and it is
cheap and easy. Just my $0.02.
Cheers, Doug

[GerryS]

That would take valuable inside space....raising the mattress and giving less toe toom under the galley...

[pigcooker]

3/4" - 1" thick rigid, under the mattress, surely
won't impede too much. Just an inexpensive
cure, which takes little time to do. If you
disagree, that's OK. Have a Happy New Year.

Doug

[halfdome, Danny]

3/4" - 1" thick rigid, under the mattress, surely
won't impede too much. Just an inexpensive
cure, which takes little time to do. If you
disagree, that's OK. Have a Happy New Year.

Doug

We've done this in the past with 3/4" white & foil faced foam with matching white duck tape along the edges to keep it intact.
It does make a slight difference but then again we haven't used the foam for several years now.
I run across it sometimes while looking for things in the shop.
Don't really need it but it does make the mattress firmer.
Danny

[Rainier70]

The other advantage to insulating the floor is that condensation is less likely to collect under your mattress. If your floor is cooler than the air in the trailer, then you will probably get some condensation, and a foam mattress can absorb it. Over time you could get mold issues.

If down the road you do get issues then, a one or two inch thick layer of blue foam glued and screwed or battened to the underside is something you could add later.

Here is a post by Nobody that shows his underfloor insulation. It shows little wear or deterioration after many years. viewtopic.php?f=2&t=59900

There probably as many answers to your question as there are builders on this forum. None are 'wrong' or incorrect. What's right for one person may not work as well for another.

I built my TD in 2006, using an HF 1800# trailer & a couple of profile drawings I expanded from quarter inch graph paper. I built my floor from ripped spruce 2x4's, 1x6 pine for side rails, & 1/2" CDX ply for the decking. After the 'floor' was completed I inverted it on a couple of sawhorses & 'painted' it with asphalt roofing compound. Contrary to conventional wisdom, the coating wasn't nearly as 'stinky' as expected, & the 'tackiness' only lasted as long as it took to dry (overnight). I then cut pieces of 1" styrofoam (Dow 'blueboard') to fit the recesses under the floor, installed them with PL Adhesive, & as an extra caution, I used small pieces of scrap wood as 'battens', 'nailed' to the floor frame with 18ga brads from my HF nailer/stapler. Almost 8yrs & 20K plus miles later (towed thru all kinds of terrain from freeway to National Forest/BLM back country roads/trails) the foam shows considerable stains/marks of travel, a few tiny 'gouges' probably from road debris, but NO deterioration or tendency to 'de-laminate' from the floor. In SE New Mexico in 2010 we encountered standing water in the streets of several towns, that in places almost 'floated' the TD. I've also driven through lots of heavy rain/T'Storms where I'm sure the tires & passing vehicles sprayed lots of water up under the TD. I've found no indication of residual moisture nor any evidence of rot in the wood portion of the floor, nor corrosion to the metal of the trailer chassis. As an aside, I live in central Arkansas where our average humidity is quite high & equipment not properly protected has ample opportunity to suffer ill effects from it...

Here's a few pix of my floor under construction





This how the underside looks this morning (not bad considering what it's been exposed to since 9/2006)

[DezPrado]

Hi there
Thanks guys, thats saved a job!
Dez - Nice to see another south islander here.
Did I know you in Wanganui?

Not sure on that one Felix. My forgettery is working overtime some days, but check your PM for an update

[felixx]

Thanks Ranier70 I appreciate the idea

I will be carpeting the bottom with indoor/outdoor carpet
I might put some foam underlay under it too
(If it is good enough for a house it should be great)

[canned o minimum]

Long story, but I have about 5 sheets of the rigid stuff under my mattress to git the bed closer to the bottom of the door...it's a 1946 homebuilt,aluminum TD