Does the length of your logs determine your cabin size or can you splice your logs to increase your wall length? I can cut logs up to 20' on my saw mill, but I want a 30'x30' or so cabin.
Experienced cabin builders have come up with all sorts of ways to add on extra room when limited by the size of their logs. One way is by using a splice or join as you suggested. I am including a picture of an old cabin in Cades Cove that has an addition that uses this method.
I am guessing this would take a little more skill that your average single pen log cabin but if you can figure out the notches, you could make it look pretty sharp.
There is even a two story cabin I have seen (maybe in one of McRaven's books) that has multiple joins. It is really more like a log mansion!
Another option is to use your logs as they are and then add a lean-to style addition on one full side, creating the extra space you need without the complicated joins.
I hope this helps. Let me know if I can help you further! ---Banjoe
PS - I'd love to see pictures of your project!
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