Stone retaining wall building advices: Why you should backfill with stone? Versa-Lok recommends compacting the angular stone as you backfill, but check the installation instructions for the type of block you’re using. Backfill about 8 to 10 inches below the top of the capstones. This will allow enough room for the topsoil and turf. Secure the capstones with a specialty landscape block adhesive, which stays flexible over time. Make sure the blocks are dry before applying the adhesive. Overhang the capstones about 1 to 1-1/2 inch. Joe and Jake use a scrap 2×4 as a guide.
By using NFC you are basically increasing the depth of your retaining wall. Most masonry blocks would be an average depth of 200-250mm, by using NFC you are increasing that depth of your solid masonry block from 200mm up to 500mm (Infill depth) or more depending on the height of your wall. It is always recommended that every third or fourth block should have part of the back edge removed. This would give a far better adhesion tying the NFC infill layer and the NFC core filled blocks creating a far stronger structure.
We also repair existing retaining walls. Many railroad tie walls or older concrete retaining walls which may or may not include rocks or boulders are beginning to show signs of failure. Often times a homeowner will build a DIY retaining wall that needs help after years of service. We serve all of Colorado out of our home office in Colorado Springs. Please feel free to reach out to us with any questions you may have. Estimates are always free and everything we touch comes with a warranty. Read more info on Best Retaining Walls Colorado.
Designing very tall walls gets rather complex when accounting for lateral pressure, as do the reinforcement options. For example, a retaining wall 8 feet tall is not just twice as strong as a wall 4-foot tall. The 8-foot wall actually needs to be four times stronger. For walls taller than 4 feet, hiring a licensed engineer to develop a design would be a smart move. At the very least, remember to follow the system manufacturer’s instructions to the letter. Plus, keep in mind that building big walls means moving truckloads of soil, gravel and heavy block.
DON’T forget to allow for drainage. Groundwater is the natural enemy of retaining walls. When it saturates clay-type soils, they swell and put excessive pressure on the backside of the wall. To avoid failure, make drainage provisions at the same time as you go about building the retaining wall. Backfilling the space behind the blocks with crushed stone and then installing a flexible perforated drainpipe (available at The Home Depot), also called “drain tile,” at the base of the wall could create the necessary escape route for groundwater. The perforated pipe will carry groundwater to each end of the wall where it can drain harmlessly away. The ends of the drainpipe should then exit on each end of the wall, and you may cover them with crushed stone to camouflage their appearance.