The following is an outline of the procedure for carrying out a major repair of a length of dry stone wall. The work is described in detail in the subsequent sections. For simplicity, the diagrams below illustrate the wall part way along its length. Unless repairing a gap, one would normally start with a wall head and then proceed along the wall.
- Dismantle the wall, setting out the stone alongside the line of the wall, while leaving enough room to work.
- Line out and clean the foundation trench.
- Put in the footings (foundation stones) along the entire trench. Place fillings between them as you work. Backfill the outside edges.
- Set up the batter frames or line bars. The use of batter frames and line bars is discussed further below.
- Raise the lines to a level about 1′ (300mm) above the foundation level. This height will vary with the size of the stone, and the experience of the waller. For smaller stone, and when you are first learning, raise the lines in increments of about 6″ (150mm), depending on stone size. Build the layers to this level.
- Raise the lines to the height of the bottom of the first row of throughs, normally about 2′ (600mm) above ground level. This may be lower if three rows of throughs are being placed. If there is only one row of throughs (as shown here), this is normally about half way up, at about 21″ (530mm).
- Build the courses up to the lines and level them off to take the throughs.
- Lay the first row of throughs.
- It can be a good idea to move stone nearer to the wall at this point, to aid stone selection. Ensure you maintain a clear working area alongside the wall.
- Where there is only one line of throughs, raise the line in 1′ (300mm) increments, or repeat points 6-9 for each row of throughs.
- When there is less than 1′ (300mm) to the level of the bottom of the topstones, or after the final row of throughs, raise the guidelines to the height of the top course, that is the top of the wall minus the topstones.
- Build the courses up to the lines and level them off to take the topstones.
- Normally the topstones are placed after the entire wall is built to the top course. However, on long stretches, or where the wall may have to be left unfinished for some time, it is worth placing topstones on the finished sections to protect them.
- Clean up at the end of the day’s work, and shift unused stones from any completed wall to the next section to be built. Leave unfinished sections in stepped layers, unless you have finished the section at a head, so that the next section will bind into it well.
