R value for interior insulation?

[rv_safetyman]

I went with spray foam when I built my truck/motorhome.  I agree with most folks who think it is the best insulation plus the fact it tightens up the panels.

Building my bus the way I did, spray foam was not an option.

For those of you getting ready to foam, *BE SURE* that you caulk the joints between the tubing and the skin.  If not, foam will get between them and expand which results in a wavy outer surface.  Also make sure the sprayer is careful to spray a couple of times with the first level being thin.  That stuff gets hot and can warp the skin.   

Jim

[JohnEd]

Jim,

Two great points I hadn't heard as yet.  Thanks!  I might add that all hollow tubing should have 3/8 inch(?) holes drilled every 6 or 8 or (how many?) inches so you can have the "shooter" fill them as they are great little transmitters of temp.  You can even do these yourself with cans of foam before the shooter gets there.  I guess that"U" channel that MCI uses would be better sprayed with "non" expanding foam a few days before the real sprayer started.

I expect I will give up the one inch of interior width and spray up to the depth of the added 1/2 inch firing strips.  2.5 inches of spray foam would be R value of ? really big.

Awnings are a must.  A white roof is a must.  And that double pane "E" glass with a reflective gold or silver coating that reflects 80% of the heat is a must.  If you can afford it.  Chaz's really scary temps measured on his glass were for single pane tinted I am pretty sure and make the case for the better windows AND awnings.

John

[rcbishop]

I repeat.... ... amount of glass is the "key"....FWIW  Want better inside temps....get rid of.....GLASS!

FWIW ....btdt


RCB