Thank you all SO much, all of this helps loads.
- I am going to look for Black Jack 57 and if I can't find it, will go with regular deck paint.
- Going to do the Deep Bedding (Shavings) instead of DLM.
- I will make the run bigger than the little overhang that's attached right now, and will fill the run with sand. But first the focus will be on the coop.
- I will use the 1/2 inch HWC inside the coop and the run - I actually checked again and there's only one hole in the coop that would cause concern (besides the windows) - and might even put some sturdier fencing against the HWC in the run in the future (saw that idea somewhere else here on BYC) together with electricity, of course. We already have everything for that right on the property.
- Plenty more ventilation will be added before winter starts.
- I will put sand in "drawers" underneath the roosts for easier cleaning, instead of traditional poop boards.
Now am I right to assume I should always close the coop at night if I use the 1/2hwc for the run as smaller critters could crawl through that, right? (Minks, etc) Or can they not get through?
For the roosts, I have some 1x6 boards readily available in the barn - are those too wide for roosts? (I mainly read about 1x4s?)
So I shouldn't worry too much about mice? I have some leftover 1/4th hwc from another project.. should I combine it with the 1/2" hwc inside the barn or just use the 1/2" hwc?
So many answers.... and somehow I still end up with more questions.

The birds I am getting are by a local farmer and she seems to have had the breeds for years now, so I am assuming they will do OK in this climate. (Marans, Orpingtons, Swedish Silverudd's Isbars and Ameruacanas) .... and who am I kidding I am sure there'll be more in the future
