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Installing a Concrete Wall

While concrete is often one of the very base foundations of any structure, its stability relies on proper site preparation.

Concrete can either be flat or shaped into three-dimensional objects. If you need steps, curbs or other form work, please let your service professional know ahead of time.

Steel rebar within the concrete makes the concrete structure stronger.

Removing concrete or paving material is very difficult work. Often it’s best to leave this to your service professional, who will have proper equipment and training to handle the removal.

Special applications: There are many different kinds of concrete used in construction today. Each type blends a variety of materials to achieve unique characteristics. Structural concrete is used for building foundations and support beams; insulating concrete is lightweight and can be used for finishes. Concrete can come in a wide variety of colors created by adding dyes to the liquid mixture.

Fixing damage to colored concrete is tricky. Getting the right blend of colors is not an exact science. Don’t expect a repair person to create the perfect match. If a perfect match is critical, consider removing and replacing the area with new concrete.

Special finishes: Concrete surfaces come in three different finishes. The most common interior finish is smooth, created by running a flat trowel over the top. This can be quite smooth—almost like glass.

Smooth surfaces don’t work well outside. A little water can turn a smooth concrete surface into a slip hazard. Contractors will texture exterior surfaces with a “brush-textured” finish. This rougher surface wicks away water and provides traction.

Exposed aggregate finish is a rougher finish and less common. Gravel is embedded into the surface, which makes it good for traction.

Special finishes and applications can make concrete virtually impervious to water leakage. This is especially important with foundations and basements when you want to keep water from getting inside the house.

In some cases, it may be necessary to add drainage systems to help wick water away from a concrete foundation. A construction expert can tell you which kind of concrete is best for your building needs.

Slope of your yard: Your service professional needs to know the existing slope of your yard so he can prepare the site for the foundation.

Your service professional will design your foundation so water drains away from your house keeping the foundation dry. He/she may need to regrade the site or add special drainage systems depending on the existing slope.

For example, a flat grade tends to cause water to sit; a sloped grade tends to drain water better.

Soil conditions: It’s important to know your soil type when planning your foundation. Drainage-the movement of water downward through the soil-is typically rapid in sandy soils and slow in clay. A given amount of water can penetrate about three times deeper in sand than in clay, so it’s apparent that soil type will affect the drainage system you place around your concrete foundation.

Clay soil is made of very fine, flattened particles that pack very closely together, leaving little space for air and water. This dense soil absorbs water slowly and retains it well. To test for clay, pick up a handful of wet soil and shape it into a ball. Clay will feel slippery. When you let it go, it won’t crumble. And when you squeeze it, it will ooze through your fingers in ribbons. Some types of clay soil actually expand in volume when wet. This can cause dramatic shifting that can damage your foundation or basement.

Sandy soil is almost the exact opposite of clay. It’s composed of large, rounded particles that don’t hold shape when you try to pack it together into a ball. Water enters sand quickly and percolates through it rapidly.

Soil made of loose rock is an exaggerated form of sandy soil. The larger the aggregate of rock, the more water will filter through it.

Soil composed of mostly solid rock is impermeable to water and just about anything else. If your soil is mostly solid rock, please let your service professional know in advance. Aggregate finish is a rougher finish and less common. Gravel is embedded into the surface, which makes it good for traction.