A retaining wall supports itself and also holds back material behind it. A wall can be made from a variety of materials such as boulders, concrete blocks, poured concrete, rocks or treated timber. The materials that you choose for this task must be able to provide sufficient resistance against the weight on the other side of that wall.
A solid base will prevent the shifting of materials that could otherwise threaten the structural integrity. Your biggest stones should be in the bottom layer. Big stones should also go behind the base, and behind the center of the wall. All stones must be laid level so none of them will slide down from the wall. Tiers that go on the top must not bring additional pressure to the tiers underneath.
Retaining Wall Drainage
Drainage is essential to prevent water from collecting behind your wall. Wet dirt or gravel gets heavier, and frost can increase the chance of heaving. Drainage should go from the wall away from the direction of your house.
Gravel is naturally going to drain, and should only need some compacting. You may need to lay a perforated drain tile where water might pool in a low spot.
Clay needs help to drain properly. Sloping in one of several directions can assist with this. If you need something more, install a drain behind the retaining wall.
Some of the materials that are naturally occurring on your property, like your soil, can create unstable ground and make the wall sag or shift. So consider eliminating the lawn and soil that was initially present. Replace that with “clean” materials which will be absorbed by the surrounding material and will create a dependable base.
The back of your retaining wall needs to be thoroughly covered with geotextile that lets water flow through without letting anything solid pass through.
Retaining Wall Varieties
Stone walls can consist of rubble walls, cut stone and boulders. A rubble wall consists of stones that are of irregular sizes and shapes that will fit snugly together. The base should be wide, with the wall narrowing as you get to the top. Compacted gravel in the joints will ensure that voids can’t settle later on.
Another option is to stack concrete blocks on top of each other and secure them in place. A compacted gravel base makes it possible for them to flex along with ground movement without incident.
Finally, a heavy-duty wall needs full-size blocks that weigh 50 to 75 pounds. Garden wall sizes are under 25 pounds. Solid and semi-solid blocks can weigh up to 75 pounds. They can form whatever angle you may need. If you prefer, you can order special corners instead.
The job of creating a retaining wall is a heavy-duty undertaking. But don’t let the weight of this project stop you from adding a wall to your property. It will increase the integrity of your yard and add a new aesthetic element at the same time.
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