We're experimenting with washing the logs. They've been exposed to the elements and an ongoing construction site for several years now, with no protection, and hoo-boy! do they look it. Some are dirty, some have a cute little fungal thing going on, and the ones nearest the ground have begun to look a little green. Eww.
It didn't occur to us that we'd need to clean the logs once they were part of our house, but a friend who built a log home counseled us in this matter. She and her husband cleaned theirs after the windows were installed and advised against that... The mild bleach solution didn't seem so mild without a ton of ventilation! So, since we don't have (many) windows installed and the gable ends are still open, we are striking while the iron's hot. Er... breezy.
My father-in-law is trying out this process on one particularly heinously yucky log. (It's the one on the bottom). I don't have a 'before' picture for comparison, unfortunately. He used a shop broom and a mild bleach solution and scrubbed half of the length of the log. After observing the result for a few days, he finished the rest of the log. It seems to be working just fine. We'll not go to that effort for all the outside of the logs, and most of the interior surfaces will not need scrubbing either. We're hoping to be able to do a much less labor-intensive washing for most of the area.
It's getting cooler here in the North Country, and so we're going to have to get this done soon, so we don't create another giant ice rink inside the house. Because you know I'm moving in as soon as that second floor and staircase are in!