Kingstone retaining wall construction tips: 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.
Why you should split blocks for a rough finish. If the end of a block will be visible, and you’d like it to match the other rough surfaces, use a block splitter. You can probably rent a splitter like this for less than $100 per day. Use a gas-powered cutoff saw like this one for a smooth cut. This saw can cut with or without water. Water eliminates the dust but creates a messy slurry that can permanently stain surfaces like driveways and sidewalks. You can rent a saw like this for about $80 per day. If you don’t use water, make sure the dust doesn’t blow into the house or on a neighbor’s house.
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.
Spacers are set to maintain spacing and support the form prior to the pour. Wire ties snug the form and resist the pressure of the wet concrete. Wales align the form and brace the studs in forms more than 4 or 5 feet high. Two horizontal walls are sufficient for most forms, but they should not be spaced greater than 30 inches on center. For lower, lighter walls, it is possible to cast the wall at the same time you cast the footer. Larger walls always require separate pours for the footer and wall. Read additional details at Building and repair of 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.