Here is some feedback I got tonight via email...
Air tight – there’s a gasket that runs on both sides of the tongue of the top of the logs. That blocks air flow. After getting rid of the French doors, I have no problems with air leakage. And I’m the top of a west facing hill in the winter.
Bugs – the logs are pressure treated with a borate solution. The solution does not wash out or deteriorate over time. Basically that protects the logs from insects and fungus. A bug would bite in to the wood and would get a mouth full of soap. No problems. The lady bugs I get and those bodies you have to sweep up every so often. Flies I have fewer flies in my home than I remember having in my mom and dad’s home. That’s just my impression.
Plumbing – runs up the central stack like the electric does to get to the 2nd floor. There’s a rubber gasket between the two floors so that the plumbing is not cracked as the house expands/contracts.
Log fit: you can come look at the logs again. The wall in the kitchen shows you exactly how they fit together. They are not “scribe” as that is where someone takes the logs on-site and carves the bottom of one log to match the other. They are machined to have a type of tongue and groove. On either side of the tongue is a gasket to help seal up from wind.
Rot: not an issue for me. The house sits on a foundation so that they are not in contact with the earth which could cause rot.
Insurance: I do not pay a higher premium as far as I know. I have State Farm. As for repairs, the house is actually quite sturdy since the logs interlock and they are spiked together. There are pictures in log home magazines of homes that have had trees fall on them. The roof had to be repaired, but the walls were not damaged at all. Kinda hard to knock down 2 stories of solid log. You would probably be best off talking to your insurance agent to determine what your situation would be (perhaps some companies charge more and some do not).
Products: Permachink is who I use. I believe their site is Permachink.com.
