Will My Pole Barn Concrete Floor Crack?

Understanding the Fundamentals of Concrete Slabs

The quick answer: YES!

If there is one constant in construction, it’s that concrete will crack—it’s essential to understand this reality before your concrete floor is poured, so you know what to expect in the years to come. 

Although there is no way to prevent concrete from cracking, there are measures we can take to control how and where the concrete floor in your pole building cracks. 

Why Does Concrete Crack?

Cracking is inevitable because concrete expands and contracts over time; if there is nowhere for the concrete to expand, you’ll notice cracking in places that might not be convenient. If you have ever seen a sidewalk that appears to have buckled, you’ve seen the effects of concrete expanding and contracting. Fortunately, the inevitable cracking of your concrete doesn’t have to be quite so noticeable. 

Relief Cuts Give the Crack A Direction

When we pour a concrete floor, we always incorporate relief cuts (also known as control joints) to give the cracks a pre-determined course. Control joints are cut into the concrete ⅓ of the overall thickness of the concrete slab.

In pole building construction, as in all types of construction, we attempt to minimize the outside corners of a concrete floor as much as possible; because the worst-case scenario is an outer corner crack, we create a control joint that runs from one outer corner to another. 

*A concrete piece should not be larger than about 12 x 12 without relief cuts; otherwise, unwanted cracking may occur.* 

Is There Any Way to Strengthen Concrete?

There are a couple of great options for boosting the overall strength of concrete:

Rebar

Rebar helps protect concrete from cracking by considerably increasing its tensile strength and absorbs weight throughout the concrete slab. This means that when a concrete floor experiences tension from expanding or contracting, it will be better equipped to handle the stress with rebar. Rebar is used to reinforce extra load areas. 

Fiber Mesh

Fiber Mesh can help reduce concrete cracking by providing structural support, but it does this on a smaller scale than Rebar. Unlike rebar, fiber mesh is not laid down before the concrete pour but placed evenly through the wet concrete. For best results, fiber mesh is most commonly used with rebar. When used with rebar, fiber mesh can strengthen the concrete while the steel rebar braces the extra load. However, the most economical method of strengthening concrete would be to use fiber mesh by itself. 

Wire Mesh

Wire Mesh helps with reinforcing the concrete and assists in reducing cracking during temperature changes. In contrast to fiber mesh, wire mesh is placed along the middle of the concrete slab. Though wire mesh assists in reinforcing concrete, it does not stop concrete from cracking in the long run. However, wire mesh does help hold the concrete together, even when it cracks. 

No matter what precautions are put in place, concrete will inevitably crack; that’s why it’s so crucial that you work with a contractor who understands how to prevent worst-case scenario cracks as much as possible. 

Now that you have a clearer understanding of what to expect from your concrete floor long term, contact us to discuss this and any other accessories you may want to add to your pole building!