How do you improve the performance of a log house?
We are planning a Honka log house. 2 stories, 1750 sq ft. The solid Finnish pine logs perform really well, people say they provide superior air quality and behave as thermal batteries / but I can't tell how close to a passive / pretty-good-house their R value brings them. I'm hoping to get some feedback and possibly alternatives on what I'm thinking. At 204 mm leakproof & sealed logs with thermal battery adjustment. i suppose the R value is about 11? Feels little but I fear I'm missing eg how it behaves in warm weather. I'm really not feeling adding extra insulation as per Honka, but I don't know if that impacts/cancels any of the below.
The build is in Three Rivers, CA - it gets hot and dry there 4 months a year. Winters are chilly but not Chicago :)
I am told the logs breathe, but I'm still really loving the idea of a passive-like ventilation with an ERV (I totally got sold on Zehnder) I have my doubts if it's overkill or "pointless" / can't find information using it in a log house.
For cooling, it'd be a mini split system. Mitsubishi probably.
Finally, I'm thinking of a metallic roof with thermobuilt insulation. Did consider a green roof but I'm not sure we'll have the room in the budget. Any alternatives? At approx 1200sf I'm hoping the roof budget to be as low as possible / below 20k.
I'm also trying to understand how any of this can help the appraised value of a house (especially the one done before the construction loan is awarded and that number sets what we'll get). See what's a good bet and what a waste of money (for the appraised value and impact on quality of life)
I realize these are many questions, Im a total newbie - I appreciate any input.