A Solid Foundation

Image: The foundation for our cabin.

Houses, like relationships and careers, need to have a solid foundation if they are going to be able to stand the test of time. Unfortunately, foundations are often under-appreciated. Most people take them for granted, or can’t even see them, until there is a problem. So, wisely, we have decided to spend a great deal of effort making sure that the foundation for our cabin is strong and solid.

At first, we had hoped that the foundation for our cabin would be something simple to construct. I guess we were wishing for level ground and a nice sand/gravel surface. Well, we didn’t quite get either. Although we aren’t building the cabin on a cliff, we do have about a 3 foot drop from the back of the cabin site to the front. Our soil, while mostly sandy-gravel, which means good drainage, has a significant percentage of clay in it, which cements it together to form a hard-pan at a depth of 18 to 24 inches. To get a level cabin, we either needed to have our foundation dug into the ground to a depth greater than 3 feet or raised on piers to a height greater than 3 feet. We decided to go for the pier option, as digging 3 feet down into the hard pan was going to be a challenge without heavy equipment. A raised foundation also reduces issues with drainage, creates a dry storage space under the cabin, and enhances the view from the cabin’s front windows.

Originally, it was recommended that we pour concrete footings and piers. However, considering the number of piers we required, and the height of some of the piers, the amount of concrete we were going to need was huge. Getting concrete to our site was going to be very difficult – not just the hauling of numerous 60 pound bags of ready-mix down ramps at the dock and up the intertidal into our site, but also the logistics of keeping the concrete dry during the trip across Johnstone Strait. After much discussion with the contractor who is designing our cabin, we came up with a novel solution – galvanized steel piers welded up from drill cores. The footings of these piers were 18 inch square galvanized plates. We buried the footings to a depth of 18 to 24 inches, soaked our sand/gravel/clay fill with water, and recreated a hard pan around the buried parts of the piers.

Piers installed

Image: Galvanized steel piers in place at the cabin site.

The next challenge was to get the saddles installed on the piers and everything level. Using a water level, we determined the height at which each saddle needed to be mounted on each pier. The saddles had about 4 inches of adjustment room, so we figured out which pier was the tallest one, and then adjusted all the shorter piers so that they were level with the tallest one. It sounds simple, but it took a bit of doing. Drilling the heavy core tubes and saddle stems at the right height was hard work, as Kennard can attest!

Saddles

Image: All saddled up and ready to go.

Finally, we “laminated” the beams. Each beam consisted of three 12″ by 20 foot long boards held together by over 100 screws. I am very thankful for battery-operated screw drivers! Once all the beams were together, they were placed in the saddles, carefully squared-up, shimmed where necessary, and then bolted securely to the saddles. After all this, they were solid!

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