I think you misunderstood. I built a barn no heat, as in no need.
The other is a log home. Logs are insulation, but more important thermal mass.
Insulation types do not vary by R factor by much. 5 for expanded styro, 5.5 for extruded. One type I forget teh name of, but is very similar in "great stuff" in a can is near 7 I think? But it comes in board forms. Very pricey.
Then you have blown in, fiber glass, HD fiber glass, etc.
Why double your price in insulation, and make application much much harder to say $10%?
If you are stick building ( 2"xwhatever" studs) your just simply bestter off with fiberglass with a vapor barrier.
Buiggest decision to be is how wide to make your walls. 4" to 12" .. My guess is 6" to 8" will be best.
It's not a simple answer, as one decision effects so many others.
Find someone locally you can actually talk to that has built garages or sheds, but not just a stereo type building. So many ppl know how to build one, but can not adapt new ideas to one.
Thats why the guys in here are so great. They are conceptual thinkers. Making a cage from a dishwasher, or a old console TV set aquarium. Must people do not thnk that way.
Long story short, I LOVE to build stuff, but do not have the means, and thought I would by now. It looks good for next year. Then I will be posting in here a ot more. I lurk a lot. As I love the created ideas in here and the people helping.
I wish I could help more, but it would have to be on more specific areas. Like built in brumation area withless insulation and outside airflow with duct work to control temps. Light tubes for natural sun light if you have lizards.
I guess my point is you don;t build a building them adapt stuff to it. So much more fun to know what you want, then make the building adapt to them.
Fun Fun topic. But geared to a 2 hour BS session over a few beers, or pepsi in my case lol.
Good luck
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Thanks for reading.
Big Tom
www.HerpZillA.com
www.HerpHelp.com