Ledgestone retaining wall repair recommendations: First of all, what is No Fines Concrete (NFC)? Basically it is just what the name suggests, concrete without any fine aggregates or sand. It consists of generally an aggregate (gravel), cement and water. The aggregate is coated with the cement slurry binding it together, it dries with the strength of concrete but with voids or air pockets. This makes the NFC light weight and allows water to pass through its honeycomb texture.
Get the first course right. Use a torpedo level to level each block front to back and either a 4-foot or 6-foot level to keep each course level and even. Set the blocks with a heavy rubber or plastic mallet. Getting the first course flat and level is extremely important, so take your time. Try to lay the course as close to the center of the trench as possible. Even a small pebble on the surface of a block will throw the one above it out of alignment. And that crooked block will affect the one above it, and so on. That little stone could eventually create an unattractive hump in the top course.
DO start with a good foundation. Your retaining wall will only be as strong its support system. For a stacked-block retaining wall that’s no higher than four feet, a trench filled with three inches of crushed rock will help keep the wall from shifting and settling. The exact depth of the trench depends on the proposed height of the wall, but follow this rule of thumb: Dig a trench to be an eighth of the wall plus three inches. For example, if you want the finished height of your retaining wall to be three feet (36 inches) tall, you’d need to dig the trench eight inches deep to accommodate three inches of crushed rock and about five inches (or an eighth of the visible retaining wall) to start the wall below grade.
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. Discover even more info at Best Retaining Walls Colorado.
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.