Wednesday, February 10, 2010

Notes on Building a Drystack Stone Wall

     I spent many years as a self taught stone mason starting in Virginia and then in New Mexico. My specialty was random rubble dry stack walls. My style and technique are fairly unique and it is work that I just loved even though it took a toll on my body as a result of my own enthusiasm.

     (Please Note: To see a rewrite of this post with better photos and text please go to

     In the summer of 2008 Allison and I found ourselves at  Breitenbush Hot Springs in Oregon as summer hires. As luck would have it they were in dire need of a stone mason to help with a large infrastructure project. I jumped at the chance even though I was paid minimum wage and a place to park our van as we had agreed to originally. It is a beautiful place and the chance to add to that was a privilege to me.
     At the outset let me caution that stone masonry is hard work that requires sturdy boots, gloves and attention to what you are doing. It is easy to have serious accidents: smashed fingers or hands, broken legs, or worse. What follows is not intended as a complete instruction but merely as notes to the process.
A safe work site is essential as well as safe practices.

     The site was next to a beautiful hot soaking pool. The objective was to enlarge the path along the pool to allow conduits for new water and electric service. The area below the pools where the wall was to be located was essentially a bog that handled the runoff from the pools. A dry stack wall was perfect because it would allow free flow of the water through this area.
     The first part was to dig a footer for the wall which is not easy in a bog. Then we needed a dry path from which to work and to move stone over. The big drawback was limited space to lay out the stones.
      As you can see above the foundation was essentially a trench filled with rubble. Obviously you want to use stone for this that is not suitable for the face of the wall.
      In selecting stones for the base of the wall you want to use the largest stones at the bottom of the wall.  They are easier to place and move into position this way and there is minimal lifting. In this case we had a back hoe and driver to help move large stones but the space was to small to allow access. We also had varying numbers of helpers to assist.

     The back fill here is rubble, again stones that are not suitable for the face of the wall. Which stones are good for the face? Hard to explain in print but basically you want a smooth face in front with an acute angle on the top that slopes downward as it goes into the wall. This is all about gravity and the next stone on top must have a tendency to slide into the wall not out. The earth is constantly vibrating even though we don't feel it and as the wall ages we want the stones to move inward, if at all, making the wall stronger and stronger.

     The above photo shows how large the base stones are and the next important principle. At regular intervals you want a stone that reaches back into the wall tying everything together. The stone with the tape on it would have looked beautiful if it had been set with the long side facing out. But structurally it would have been weak and wanting to tip out of the wall. As it is set above it ties the wall together and makes it much stronger.
      You can also see here how the tops of the stones slope downward as they go into the wall. And lastly you can see how the fill stones are rounded and not suitable for face stones. As the wall gets higher you will notice the fill stones get smaller.

     The wall takes shape and the conduit ( the whole reason for this wall ) is in place. The white pvc pipes sticking up out of the rubble are for the railing.

      This photo shows another principle. Always tip your wall into itself or the bank that you are holding back. A rule of thumb is to tilt it in at least one inch for each foot of rise.
      The blue hand truck in the background came from Harbor Freight and turned out to be quite good. It had large pneumatic tires and held up to lots of abuse. The buckets hold chisels, 3 # mallets, gloves, tape measure, etc.

The completed wall.

You can see here how much the wall leans into the bank. I call this the batter.

We added these steps to the left end of the wall.