Insulation query

[DasBaldGuy]

R value of 3/4 ply is .91 +/-....

the lowest I could find for 3/4 foam was R = 2.6

We are talking about the 3/4 inch "blue" styrofoam 4x8 sheets available at bigbox home improvement store, correct?

[Arne]

I used pink, as that is what h/d had available.. I think the white with foil is higher..

R-Values Per Inch For Common Insulating Materials*

Insulating Material Avg. R-Value Per Inch
Batts or Blankets

* Mineral fiber (rock, slag or glass)

3.25

Loose Fill

* Mineral fiber (rock, slag or glass)

2.2

* Cellulose (milled paper and wood pulp)

3.4

* Vermiculite, exfoliated

2.13

* Perlite, expanded

2.7
Rigid Board and Slabs

* Expanded polystyrene, extruded (cut-cell surface) and molded bead-type

4.0

* Expanded polystyrene, extruded (smooth-cell surface)

5.0

* Expanded polyurethane, refrigerant 31 exp.

6.25

* Polyisocyanurate

7.04
Building Board Sheathing, regular density 2.64

[eight433]

I used 3/4 plywood, AND 3/4 pink insulation on the walls. 2x2 rafters for the ceiling, with 1 1/2 white Styrofoam insulation in the roof, AND a fantastic fan with two windows. I had it outside the other night with a 10 dollar coil/fan heater and it would keep it HOT inside of that little camper. It was 18 degrees and windy that night. It got even better after I put weatherstrip around the doors.

IMO, you can never over insulate. I might even insulate my cabinets, as that is the only place I feel cold air yet.

[stmaryscowboy]

Has anybody used the original 2X2 wall construction and used the spray in polyurethane in the walls, ceiling and in the floor? If so does it help with structural rigidity? I my way of thinking it would help in maintaining the temperature, humidity, noise and help make the frame more rigid. I would appreciate any input.

[felixx]

Hi
There is a guy in Bury who is selling tears on e bay http://cgi.ebay.co.uk/american-teardrop ... dZViewItem
if you look at his photos he appears to have used 3/4 ply and cut it out to lighten it and then insulated the voids. I'm not sure if I would want to go that route myself but every one to their own.
I think that camping in our weather conditions would need insulation and good ventilation. Having said that I have been thinking about 3/4 ply and covering the interior with that thin cord carpet type material that they use on the inside of our buses.

pieface

I did that.. cut voids and insulated em..
works well