Consider getting an insulated construction tarp to lay over the camper. It won't have as high an r value as sheet goods but because it is more form fitting you might still get better results. If you use straw bales, get a cat too ;-)

I do have a dog- How many BTU's does a 30 lb. dog produce?

Posted By jdebree on 02 Nov 2012 05:16 PM
I do have a dog- How many BTU's does a 30 lb. dog produce?

A sleeping & snoring long-haired geezer, or a wakeful young alert night-watch dog? :-)

http://jn.nutrition.org/content/121...8.full.pdf

Mammal output does not scale linearly with size, and it varies with fur (short-hairs need to put out more heat than long haired dogs to maintain temp) but you can bet that a 30lb sleeping dog is probably putting out more than 50BTU/hr, less than 150BTU/hr independent of other factors, but I'm sure the output varies widely.

I think the cat would be more for mouse control than a mini-heater.

By the way, we built a 14x14x8 (1600+ cf) efficiency apartment inside a metal bldg.
1. The bldg walls and under roof were sprayed with 3" of open cell foam.
2. The room's walls were 2x4 with r-13 fg batts.
3. 12" of batt over ceiling.
4. 2" pink board under the 3/4" OSB floor. The floor was framed with 2x4s so we had 1.5" of airspace between the foam and osb, so I laid aluminum foil over the foam to create a radiant barrier.
5. Pole barn quality window on the exterior wall

In the winter, we use a 1500watt (about 8" cube) heater that will run for maybe 20 minutes per hour in single digit temps. And the floor is never shockingly cold like the concrete in the shop area.

Nice idea. Just make sure that the house is well made and air sealed so as not to cause fire and burn your house.