Three Types of Foundations Used for Home Construction

Most people will never try to understand the physical components of a structure that lie below the flooring of a home. If and when the time comes for a foundation repair, understanding your foundation type and characteristics will lead to the best service and solutions. Contractors build homes in Arizona using three different kinds of concrete foundations: monolithic, post-tension (a type of monolithic) and stem wall foundations.

Monolithic concrete foundations are the most common. The two parts of the word monolithic – mono and lithic – are indicative of its definition. Mono is a prefix that means one, or single, as in monotone, having only one pitch. Lith is the greek root that pertains to stone or rock. So a monolithic foundation consists of one continuous, solid piece of concrete – typically in a rectangular shape. It amounts to a single, simple slab of concrete, and is usually built with rebar around the perimeter for strength and an internal wire mesh for stability. A monolithic foundation, sometimes called a “slab on grade” foundation, does not use any stem walls or rigid internal structure, but sits atop a layer of gravel on the excavated ground. The most common cause of damage for monolithic foundations is that they change shape. Over time, the sides and corners of the foundation slab begin to sink downward, due to the concentrated weight from walls around the perimeter. This causes cracking, structural damage and the appearance of a rising interior floor. Understanding the root of the damage in a foundation is the first step toward implementing thorough, lasting solution.

The second type of concrete foundation, a post-tension foundation, also falls within the family of monolithic foundations, but also contains an inner tension that is created after the concrete is poured – which is why it is called post-tension, or “after-tension.” Whereas a regular monolithic foundation probably contains rebar inside only the perimeter, a post-tension foundation contains a horizontal grid pattern of steel reinforcement cable with protective covering throughout the inside of the slab. As the concrete warms, the steel cable become tense, allowing the foundation to maintain shape with less cracking. The result is a strong foundation that allows some flexibility in its shape. This is particularly useful in places like Arizona, where the soils are prone to move, shift, or expand under concrete foundations. Unfortunately, over time, rebar reinforcement is subject to invading moisture from the exterior that can cause oxidation and wearing of the foundation material. With a full repair, waterproofing and painting method provided only by seasoned expert James Belville and Concrete Repairman LLC, Arizona’s homeowners can stop these destructive effects.

Stem wall foundations are the least expensive of the foundation types, and they are the least structurally stable solution that you’ll find in Arizona. A stem wall foundation is, by definition, not monolithic, and not made up of a single continuous piece. Stem wall foundations rely on an underlying pattern of short, upright walls – both around the perimeter of the foundation and along the lengths of interior room walls. These upright walls protrude slightly above the surface and support a flooring layer above. A very common and dangerous problem in stem wall foundations is the formation of horizontal cracks along the foundation, usually above the ground. This visible cracking often occurs because moisture invades beneath the surface of the paint, rises up toward the steel, and begins to cause oxidation. This rust and corrosion deteriorates the concrete around it, leading to cracking, crumbling and structural instability. If you or someone you know experiences these kinds of problems, learn about why Concrete Repairman’s expert James Belville has the only concrete repair company in Arizona to offer complete restorative repairs for damage like this.

Until their residential or commercial foundation begins to deteriorate or fail, the characteristics of concrete foundations will remain mysterious to most home and property owners. It is common for a company to make foundation repairs without going very far beneath the surface, where the problem starts. James Belville knows that most repair companies and contractors often neglect to go deep enough, they fail to create a lasting seal, and they almost never repaint the surface of a repair. With a better understanding of their foundation type, homeowners and other property owners can take the correct steps for repairs and maintenance. If you have questions or concerns about your foundation, or if you would like an estimate on the right solution, call James at Concrete Repairman LLC, the Valley’s best concrete repair experts, at (602) 418-2970.