What Is a Slab Foundation?

While not as common as crawl spaces or basements, slab foundations are quite popular around Michigan, and they are a good choice for any homeowner who’s looking to build a home on a moderate budget. But aside from their low cost, they’re also much easier to construct than other foundation types. The major downsides are that they don’t offer room for a basement or crawl space, and they can easily sustain damage due to frost.

Let’s delve more into this foundation type and explain all there is to know about slab foundations.

What Are Slab Foundations?

Simply put, a slab is a construction element that mixes concrete and steel rods. The latter part is there to increase their strength and reinforce the structure. The point is to make it as robust and resilient as possible. Slabs are four to eight inches thick in most cases, and some can be up to one foot in thickness. Their edges are even bulkier to provide more strength. Construction crews pour the concrete all-in-one, which means that slabs are monolithic structures.

Just like any other construction element that uses concrete, slabs need time to cure. This process can take up to 28 days in some cases, depending on the climate. Yet, after a couple of days, it will be firm enough for builders to remove the forms for concrete pouring. After another few days, a week or so, the slab will provide enough strength for the crew to walk over it while working on other phases of home construction.

How Slab Foundations Are Built

Although they’re relatively cheap to build, slabs are also easy to install. What’s more, builders need little to no preparation to begin the actual process. Here, we’ll go through the whole procedure in several easy steps to help you understand how slab foundations come about.

• The first step is to determine the width and length of the slab. This will depend on the type of structure (floor plans and overall design) that will sit atop of it. The crew will also take into consideration the surrounding ground conditions. If the circumstances are ideal, the slab foundation will fit the future home above it completely.
• Once they do all the measuring, the team will prepare the ground. This includes removing all the rocks, branches, and roots to make sure that there is no unnecessary junk that could jeopardize the slab structure.
• The next step is to frame the concrete slab with planks. Most construction teams will make it easier by using pre-made 2 by 12-inch boards.
• Afterward, the builders will use rakes and other garden tools to make sure the ground is as flat as it can be.
• When the ground is flat enough, they will dig footings inside the slab area. In case you’re not familiar with it, a footing is a layer under the slab which we usually fill with different types of soil including sand. Essentially, it holds the weight of the structure that sits on it.
• After that, it will be time to employ tampers to compact the mixture of soil and sand in the footing. This process makes the molecules of dirt tight, which in turn makes them capable of holding the weight.
• The penultimate step is to pour the mixture of mortar and sand into the footing. The mixture needs to cover the whole foundation and cure.
• Lastly, it’s time for the concrete to go into the footing. As we’ve said, pouring the slab is an all-in-one process. Builders do it in one take, which makes the foundation monolithic. Some teams will add post-tension cables and steel rods to increase the slab’s strength and durability.

Slab Foundations: Benefits and Disadvantages

The pros:

• Slab foundations are budget friendly. Both the materials and labor are inexpensive, requiring little to no maintenance.
• This type of foundation is simple to build. As such, slabs won’t hold back the overall construction process.
• Slabs are pest and mold-free. They enclose your home from its lower side without leaving any openings for rodents or mold to come inside.
• Slab foundations are easy to extend with professional help.
• Most importantly, slab foundations are long-lasting. They can easily last more than a century if you maintain them properly and the construction crew does its job well.

The cons:

• Slab foundations don’t come with additional storage and living space like basements and crawl spaces do.
• When it comes to plumbing problems, the repair crew will need to jackhammer the slab to reach the pipes underneath. 
• Like all concrete structures, slabs can crack with time usually due to high humidity as well as frost and freezing temperatures. To prevent this, homeowners should water the slab occasionally.

Who to Call for Slab Foundation Repairs

In case you’re having trouble with your slab foundation, you can always contact FSM. Providing services to the Detroit area, Grand Rapids, Traverse City, and nearby in Michigan, our team will help you repair your foundation in no time. You can schedule a free estimate now and professionals will come to your home in no time. Remember that it’s important not to delay repairs as problems like these can easily turn into a living nightmare if you allow them to.

Leah Leitow

Content Writer

Leah is a Content Writer for Groundworks with nearly ten years of experience working in the foundation repair industry. Her experience ranges from working with homeowners to find the right solution to training inspectors and staff. In her background as a Michigan journalist, she gained invaluable insight into people's lives throughout our state. Leah lives in metro Detroit with her husband and two sons.

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