This past summer, I re-designed a raised planting bed that was constructed out of an old railroad tie retaining wall that was decaying and crumbling over time. I had the opportunity of watching the crew at work, so I figured I would share the installation process with you. There is a correct method of installing the wall to ensure that it is going to be functional and permanent. I used the Nicolock Firma Wall System Toffee/Onyx stone for this particular project, but if you are using another material, such as natural stone, the process is similar.
First, the original railroad tie wall had to be demolished and removed, while the soil around the perimeter area had to be excavated. It is important to dig down the equivalent of one course of block (eight inches in this case) and use a leveling device to obtain an even base. Add a recycled concrete layer under where the wall stone is going, approximately two-three inches at a time, and use a tamper to compact it. (If starting from scratch, it is recommended to use the recycled concrete as a base under the entire area where the topsoil is going and also use a layer of fill in between the topsoil and base to ensure proper drainage.) Select your wall blocks and lay them out across the base. Continue laying the stone block by block until the entire perimeter is created. Measure and make cuts with a masonry saw to complete any angles needed to fit the pieces together at the corners. This first step in construction takes the longest and is most crucial in determining the success of the rest of your project.
Continue with the second course. Select your wall system blocks and stack them in a staggered pattern on top of the base course so that the seams are overlapping. Dry-fit each block first so that the vertical joints are staggered as seen above. This creates a stronger and more stable wall.. Remove the block and apply a layer of mortar on the first course. Add the next course and tamp the block into place with a mallet, and repeat.
Continue building courses. At the third level, insert a drain pipe, while leaving an exit point for the drainpipe at one end of the wall. This will ensure proper drainage once your wall is complete. Continue the process while carefully aligning the block in a staggered pattern and mortar the layers until the desired height is obtained. Note that the final and top layer is the wall capping, a more decorative layer that prevents moisture from running down into the open cracks of the lower layers and which adds the aesthetically pleasing finishing touch! Mortar the wall cap in place as you did for the other courses.
Depending on the size of the wall, a project like this can take anywhere from a couple of days to a week or more, but it is worth the while to take your time and have good results. Once your wall is constructed, bring in new organic topsoil and plantings to complete the project.
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Author: Lee@Landscape Design By Lee 2018. All Rights Reserved.