floor insulation

[yycwrangler]

Hi Guys

Time to get the cargo trailer in shape for the summer season..I want to focus on insulating the floor. Unfortunately the finished floor is down, so going to have to insulate from the underneath. I'm thinking rigid glued and screwed. Might even put a carpet down but prefer not to.

Question, do you think an R10 will make a noticeable difference and can anyone suggest a type of insulation that would be durable on the underneath. Obviously a rigid insulation but pink/blue or something else. Could even cover it in 6mm ploy before putting it in place.

Thought ?

Cheers
Al

[John61CT]

If you'd consider carpet why not foam there?

Polyiso has best R-value per inch thickness.

3M and other specialist adhesives work well.

Careful not to add too much weight, more ply likely not needed.

[ZColorado]

Spray foam, water tight and the big guys use it too.

cons: it's expensive.

I worry about rigid foam holding moisture against the plywood floor and rotting it out. Spray foam should seal it?

[Padilen]

I've insulated mine, then used drylock paint.
I live on a dirt road and have not seen any mud underneath trailer. So I have little concerns for moisture and rot.
I used some scrap 1" glued on with liquid nails. This isn't necessary, but kept me from having to cut out for things on the underside of my trailer. Then cut 2" forcing it between frame rails, using liquid nails. After I was done, I caulked by frame/insulation seams. Then painted.
Pics probably in my build thread It's sort of mine.

Sent from my XT1635-01 using Tapatalk

[John61CT]

Plywood should be fully encapsulated against moisture

regardless

[Padilen]

Plywood should be fully encapsulated against moisture

regardless

Having scraped TT's I never saw one that rotted up. But anything is possible.

Sent from my XT1635-01 using Tapatalk

[yycwrangler]

Thanks Guys:

Paliden - did you use rigid insulation underneath and then covered it with dry lock paint. Which of the ridges did you use and any thoughts on it's R value. Did you find it effective in reducing the cold floor

zcolorado - would love to spray foam but as you said expensive.

John61 - All my hardwood floors are down and cabinets in place so it would latke on hack of a lot of work to take all of that out to put insulation down..yes I should have done that but I didn't.

I did look under my trailer today and it has a black coating on the plywood..Would that be a water barrier protector

[John61CT]

yes

find out exactly what, and add more

Then use an appropriate engineered adhesive to fix rigid foam board from underneath.


Could flip the trailer, and use 2-part pourable.

http://www.uscomposites.com/foam.html

Or spray foam, Dow 2-part kits are good.

But be exacting wrt prep, temp humidity specs etc. Or get pros to do it, ideally for cost arrange for them to hit your trailer with leftovers at a bigger job site.

Maybe too late for you, but in general, the cabinetry buildout stuff is ideally modular and easily removed for this sort of maintenance work in future.

[John61CT]

Or use a tough flexible foam layer inside - Armaflex / K-flex Insul-Sheet / Ensolite - then carpet on top for visible areas, plain thick foam bottom of vabinets.

Gym flooring puzzle mats may be cheaper but less R-value.

[aggie79]

Plywood should be fully encapsulated against moisture

regardless

...or left unsealed on one side so that any moisture intrusion from the opposite side can evaporate through the unsealed side.

[Andrew Herrick]

Plywood should be fully encapsulated against moisture

regardless

What defines fully encapsulated? At what hydrostatic or hydrodynamic pressure? Maximum permeability rating at worst-case scenario ambient humidity and temperature? :p

I'm pulling your leg a bit, obviously, but "fully encapsulated" means different things to different people.

I'm more of the opinion, as Aggie79 said, to allow the plywood to diffuse moisture on at least one side. That doesn't mean leaving it unprotected; water can diffuse through many paints, coatings and wraps. As long as the rate of drying exceeds the rate of wetting, you're usually golden.