How Often Do You Need Expansion Joints in Concrete?
At Kaloutas, we know that interior and exterior concrete flooring is expensive. For that reason, you need to protect your investment from the most common form of damage in concrete: cracking. The most popular way to protect against random cracking is the installation of expansion joints. In this post, we’ll talk more about expansion joints and answer the question of how often you need them in your slab of concrete for optimal results.
What to Know About Improving Your Expansion Joint Concrete Slab
What Are Expansion Joints?
As concrete dries, it shrinks and forms to the topography of the ground it was poured on. Some parts of the concrete shrink more than others, pulling and stressing other parts of the slab. Similarly, as concrete experiences temperature changes, it expands and contracts – sometimes more in some parts of the slab compared to others. Expansion joints are full-width cuts installed in professional concrete floors and walls that allow the concrete to expand and contract without cracking randomly. These joints isolate different parts of the slab so that the whole slab can move without straining certain parts more than others.
In other words, an expansion joint gives a concrete floor some breathing room.
How Are Expansion Joints Created?
Expansion joints are cut depending on the temperature around the concrete. In hot weather, expansion joints are usually cut with grooving tools while the concrete is still wet. In cooler weather, expansion joints can be cut with saws after the concrete has hardened a bit. Expansion joints cut through the entire width of the slab and are then filled with some sort of filler (a sealant or compressible material).
Other Kinds of Concrete Joints
It’s worth mentioning that expansion joints are just one of several types of floor joints used to mitigate or control cracks in concrete. The most common type of joint – a control joint (also known as a contraction joint) – is put into the floor during the curing process to prevent random cracking throughout the floor as it dries.
Isolation joints separate a concrete slab from another surface, like a structural beam, wall, or pipe (this is because these other surfaces shift at different rates than the slab itself). Cold joints are created to separate a new pour of concrete from an older one.
No matter the joint type, they all require proper installation and maintenance to protect your concrete floors from cracking and to keep the joints functional. Read our blog, “What Are Expansion, Construction, and Control Joints And Why Are They So Important?” for more details on different types of concrete floor joints.
How Often Do You Need Expansion Joints?
The number of expansion joints required for a concrete floor – and the distance between each one – may vary for a number of reasons, such as the length and width of your floor slabs. Generally speaking, expansion joints should be no farther apart than 2 to 3 times (in feet) the total width of the concrete (in inches). So for a 4‑inch thick concrete slab, expansion joints should be no more than 8 to 12 feet apart. They should also be placed around structures that go deeper than the concrete slab, such as columns or walls.
How Kaloutas Repairs Expansion Joints
At Kaloutas, we can repair your concrete expansion and control joints so that they look better than ever. Our process follows the following steps:
Grind away any unevenness in the surface
Clear out any chipped coatings or debris
Use an epoxy and concrete expansion joint filler to recreate a smooth, level surface
Cut a new joint in the repaired concrete floor, and fill it with a flexible joint filler
Once the expansion joint is repaired, we can also repair or replace the epoxy coating on the surrounding floor – at this point, the floor is safe, attractive, and durable for many years to come
Floor joints are too important to be neglected. If you need industrial flooring and joints fixed and maintained, contact Kaloutas’ professional flooring contractors. We’d love to help you with your project, and can ensure quality results!
Kaloutas is an ideal vendor for these needs:
Kaloutas is New England’s premier contractor for commercial & industrial painting, flooring, and related services. Established in 1987, Kaloutas has become a trusted resource for general contractors, facilities managers, and building owners from Connecticut to Maine. Our team prides itself on high quality workmanship, jobs done on time & budget, and tackling complex projects that other contractors don’t have the experience or resources to handle.
Contact us today for a painting or flooring estimate, or give us a call at 978−532−1414 to learn more.