In Reply to: How many BTUs posted by Island Mike on December 26, 2017 at 13:46:28:
BTU's flow based on Delta T, which is temperature differential from inside to outside. The higher the differential the higher the flow. You loose twice as many BTU's when your Delta T doubles...
But I have also found that rolling condos have a lot of what is called infiltration. That is Air leaking around doors and windows and badly sealed floors, ceilings, and walls. Infiltration is warm air going out and cold air coming in. You have to heat the cold air coming in. Most old houses and rolling condos have as much heat loss from infiltration as they do from conduction (heat flow through walls and ceilings and floors). Insulation is also a key factor, and in a rolling condo you are limited to the thickness of the walls. Your shed must be sealed up better then the condo. Also has less windows and doors. Windows are another big loss of heat through the glass. Single pane glass has a real lousy (as in next to none) insulation factor.