Cracks in concrete are a common sight, but many homeowners don't understand why they appear or if they are dangerous. In reality, 95% of cracks in concrete are harmless and nothing to worry about. Cracks can be caused by a variety of factors, such as moisture loss, improper subbase preparation, and heavy vehicles driving on the concrete. While some cracks are inevitable, contractors can take steps to minimize them, such as using reinforcement and correctly placing and spacing crack control joints and expansion joints.
When moisture finds a path in or around the slab, it can cause serious damage to the concrete. This is especially true in areas with wet weather and clay soil, such as Tulsa. You may see a series of cracks (called D-cracks) forming parallel to the joints and brackets. It is important to note that concrete is very difficult to install and the structural integrity of your home is essential to its safety.
DIY solutions are not recommended. To minimize cracking, concrete should be installed on an even, compact, well-drained base. Otherwise, when excess water on the ground under the concrete freezes and thaws, it rises slightly and displaces the concrete on it, leaving it susceptible to large cracks when heavy vehicles drive on it. Wire mesh can be used to reinforce the slab and provide a controlled way for the concrete to move with expansion and time. It usually comes in rolls or sheets and is placed on the concrete slab, approximately in the center of the slab; on a 4-inch thick slab it would be approximately 2 inches from the top and 2 inches from the bottom of the slab. Shrinkage cracks should not be continuous or structurally important, although they may cause water to enter through the wall.
For example, if you have a 4-inch concrete slab, the maximum joint spacing should not exceed 8 feet. Driving a car on a sidewalk or having a moving van parked in a driveway could be too heavy for concrete to handle. A disadvantage is the possibility of cracking, and instead of being able to change a tile or two and fill the grout, the floor is left with noticeable cracks. When the stress becomes too great for the now hardened concrete, the slab cracks to relieve stress. You are more likely to see such cracks on the floor of a garage that has a hard, smooth surface with trowel than on one that has a broom finish. In conclusion, while cracked concrete may seem scary at first glance, it is actually very common in almost every house that has a concrete floor. To minimize cracking, contractors should take steps such as properly preparing the subbase, making sure that the concrete is not too wet, using reinforcement where necessary, and correctly placing and spacing crack control joints and expansion joints.
