The BIG project for the summer has come and gone. Leveling the sinking cabin on our property has been a head scratcher for some time now. It has taken all summer (two and a half months here in Alaska) to research and prepare for this project. We gathered lots of information from several long-time Alaskans and builders to reach the final decision. And after three long days of hard labor we did it!
This cabin has been sitting (just barely) on six posts for the last ~20 years slowly leaning to the left while the permafrost swallows its wooden foundation. The left side actually made it to the ground which is what has been supporting the cabin for who knows how long.
We decided to use treated 4x6's and 4x4's to build cribbing to increase the footprint therefore the stability. Those will be filled with gravel and a concrete pier block will be set on top, somewhat buried in gravel. The pier block will have adjustable mounts at the top bolted to a piece of 4x4 which will be spiked to the bottom log thereby connecting the cabin. 
Hammering those spikes was no easy task, even with a hole pre-drilled into the wood.
I cut most of the wood pieces for the cribbing with the sawzall.
Bracing the cabin, inside and out. We did this so the cabin would resist shifting somewhat during the process. I told Andrew it looked like a wooden spider web inside the cabin.
Braces on the outside.
A completed crib set (upside down).
Now the jacking begins. We used four different jacks the whole time. The big red high lift jack, two four-ton jacks, and a six-ton jack. Throughout the process we lifted the back two corners together and then would move to the front and lift those two corners together. The middle cribs were put in last.
The first step was to lift the cabin just enough to create a little space between the log and the post attached to it. Then the spike was cut and the post was cut out. It was hard to get started because there was such little space to work with. We needed a good, solid base to set the jack on but both would not fit between the ground and the log. 
You can see the jack is just sinking into the ground.
We used two jacks on each corner/end of the cabin. That might have been over kill but it's our first time. We'd rather be safe than sorry. Some friends down the road say a log cabin is a living house, and by the noises our cabin was making, it was definitely alive.
Nothing bad was happening here, just a funny picture I ended up with. It seems like Andrew was having some sort of mental block or lapse.
That's all the space we needed.
First post out, five to go.
It was crazy to watch the jack work backwards. Instead of jacking the cabin up, sometimes in the beginning it jacked itself down into the ground. In the picture above, we needed to be jacking up the log on the ground beside the jack.
When we finally got enough space to use a larger base for this jack, it had five layers of 2x4 pieces in the ground under it.
With more room the jacks are much better situated now.
Now onto the front of the cabin...a problem arose pretty quickly. As the cabin was being raised in the back, the whole cabin was moving ever so slightly to the left. So when we moved to the front of the cabin, the floor joists sitting on top of the bottom log (on the right side) were just barely hanging onto the bottom log. Plus, on both sides the floor joists are not really even attached to the bottom log. There were literally two or three nails holding it on top.
So, we strapped the log below the joists to the log above the floor to hold them together. Then, strapped a come-a-long (what a handy tool) to the bottom logs on both sides of the cabin and pulled the one out-of-place log back under the cabin where it belongs. 
Much better
Boss just hung out and watched from a distance wondering when it was his turn to be played with.
In the next few pictures, I love seeing the space grow between the ground and the bottom log. You can judge it by the increasing amount of wood that is beside the jack. 
Taking care of the third post, first one on the front of the cabin.
Back to the back of the cabin....first pier block in place! In theory, this bolt on the pier block will allow us to continue leveling the cabin in the future as the cribs shift and sink or whatever they are going to do. Ahhh...the joys of permafrost!
About to put the second pier block in on the back.
Just to throw in a little more excitement, the cabin again wanted to move to the left as we were jacking it higher. So, we added some more bracing and also used the come-a-long to attach the back of the cabin to a spruce tree to hold it in place :)
Adding gravel to the cribbing. Notice that 4x4 spiked into the bottom log of the cabin. That could only be done just before the cribbing was placed under the cabin. So, after we jacked the corner up as high as it needed to be, Andrew hammered two spikes through the 4x4 into the log. Talk about hard work...upside down hammering of spikes! Yikes!
The last step for each crib after putting the pier block in place was screwing in the bolt and nailing in the final nails through the bracket. This picture shows how much the cabin moved on us before we added the come-a-long for bracing. It was once centered and will be again soon after the cabin has a chance to adjust to its new legs. Four more sets to go.... 
With room to work under the cabin, Andrew is cutting out one of the middle posts.
Front crib sets and one middle set are done!
Nailing in the back side of the bracket. 
The last one! Hip-hip hooray!
The finished product! We brought the whole cabin up 20 inches and maybe a little more so in the back. Now, we'll have fun monitoring the initial settling and fixing it again.
The right side of the cabin (as it would be facing the door).
The back.
The left side.
Job well done! Go us!