New trailer arived Tuesday-truck on the way here-maybe next week before arrival-who knows for sure?....started with the insulation last night....not used to all this work!....too much vacation and the rainey weather doesn't help the "authur-itis"....Income tax prep tomarrow so I can rest-them back at it Saturday and Sunday.....geof

What kind of insulation are you using?

polyisocynate board called Tuff-R...6.3 per inch plus refletive foil....2 inches total with spray can foam as a gap filler.....trailer is 8'-2" wide 6'-8" high and 35' long inside with .063 alum sides- steel 1''X 2'' tube frame 16" on center sides and top-8'' tube X 12" on center frame-3/4" am-teck floor..Total R- factor is 15 top/sides-floor might be sprayed with polyiso/rhino if too cold....one 13.5 a/c and a fan for air movement and a 1500 watt heater.....geof

Geof. I am not sure of what the correct term to describe this is but im wondering about heat/cold transfer from a metal outer skin to the steel wall studs.

This might not be much of a problem in a trailer but I am considering a motorhome with a lot of winter use.

Even with good insualtion between the studs would there be a transfer of cold between the metal skin and metal studs creating cold spots.

I just used some polyiso for insulating a passive solar heating area on a house. 2 1/2 inches thick. Got some sheets left over from a bigger project. The price was right - free. I would be curious about what method did you use to cut the panels into smaller size to bit between the studs etc?

.....In the Airstream in 10 degree weather the "hand thermometer" could just barely feel the aluminum studs with a constant 70 degree indoor temp. I was going to induce some steam to look for frost spots to check my work-but I got distracted and the weather warmed up. Followimg my winter vacation, when I got home form Florida, I got a deal on the new trailer-so I really got sidetracked as it arrived 7 weeks early so the Airstream is on a friends farm east of here. With the new trailer, an R-6.5X2" strip every 16" on center with an R-14 cavity insulated shouldn't make that much differance except in your neck of the woods where I would add another 1" of polyisocynate foam board for a R-21 or anotherwords R-14 over the stds with a R-21 filling for the walls and ceiling....the floor being another issue, as the heat loss is only 10% when not moving...another thing I would suggest is some alternate methods of heating your rig-if one unite poops out-which has been known to happen-there would be other ways of maintaining heat....maybe a combiation of electric and propane with the possibility of using engine heat through a series of heater cores and fans....maybe an indoor fireplace/wood heating stove/propane radiant energy source ......geof

DUH!....cm...I forgot your last question....I'm using my panel saw or I could use my table saw to cut the foam sheets to fit snug between the studs....any gap gets the spray can foam......with a steel edge I guess I could get close with a box cutter if I was in the mood but I'd perfer the panel saw-'cuz I'm lazy.....geof

Our MC8 bus conversion has spray-foam insulation. No heat or cold transfer from metal exterior to inside --- interior is 1/2" plywood.

My Airstream is another animal. In the summer you can indeed feel the heat transfer from outside to inside. No comparison to the bus!!

FWIW

don

Don-I have looked into the spray foam around these parts and the installers are less than relyable-so I'm doing the foam board.....spray foam is around $1.00 per board foot with you doing the clean up-whereas the foam board is 28 cents per sq ft not including labor which ammounts to about another 25 cents a sq ft.....the interior liner on my trailer is 3/8 inch Dougles Fir...I will have a 2 inch layer except for the 1"X2"square tube studs with the 3/8" plywood and the .063 Alum exterior....geof