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Why You Should Seal the Joints in Your Concrete

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Joint Sealing

Water can be the bane of your existence, primarily if it’s found its way inside a place you would rather it not be. But don’t worry, there’s a solution for that. We’ll get to that in just a minute. The first thing to understand is what a joint is. A joint between two slabs of concrete is essentially a point where an expansion joint and control joint occur. Expansion joints are generally 3/8″ to 5/8″ wide and allow for thermal movements within the concrete structure.

These kinds of joints can be found in your home’s driveway, sidewalks, patio or pool deck, and if water gets underneath through these joints, you will eventually have issues with soil erosion that causes voids under your concrete slabs. Foundation Support Specialists is your local joint sealing professionals who can help get your joints under control.

What Are Control/Expansion Joints, and Why Is Concrete Poured This Way?

Concrete poured this way is called concrete joint control/expansion joints. The purpose of the control joint is to prevent concrete from cracking when it shrinks as it cures.

The purpose of the expansion joint is to allow for movement of the concrete slab and the building structure.

Control/Expansion Joints are usually placed every 8-10 feet in new construction. In existing structures, they are often placed at door openings and window openings where there is a change in floor level or where there may be a change in temperature (for example, near an air conditioning unit).

Why is this important? Concrete is made up of sand, gravel, and water. The water evaporates when it dries out, leaving sand particles and gravel behind. These two ingredients are heavier than your average concrete mix, so they settle down into your joints. But as the concrete dries out, it will shrink back up again — and if there aren’t any inlets for this movement, your slab will crack. 

The best way to prevent this is to leave space between each section of poured concrete. This will allow the movements to take place without causing damage to your new driveway or sidewalk!

Prevent Water From Seeping Under Your Concrete

Concrete is a reliable, durable material that can last for decades if properly maintained. Concrete joints, however, are another story, and they suffer from several problems that can lead to cracks in concrete and leaks over time, resulting in the need for concrete repair.

Concrete joints can be problematic. They’re typically filled with sand, which is excellent for absorbing water but not so great for keeping it out of your home. When water gets into the joint, it can cause cracks and other damage over time.

Joint sealing is an easy way to prevent water from seeping under your concrete, but it’s also a vital maintenance step if you already have cracked or damaged concrete.

According to Foundation Support Specialists, concrete joints leak mainly because they’re not sealed properly. When cracks form in the joint, water seeps through and collects in the crack, leading to a leaky mess outside your home or business.

Concrete joints can crack in two ways:

Cracking due to temperature changes: Concrete expands when it heats up and contracts when it cools down. Concrete that has been installed with too much space between slabs will expand at different rates than adjacent slabs. The temperature changes can cause the joints between slabs to crack or even separate.

Cracking due to moisture: Water will seep into a crack in the concrete and freeze at night (or during cold weather), expanding as ice and breaking apart the concrete itself. This is why you should never close off an unsealed joint with a caulk or other sealants that contain petroleum products — these products can make matters worse by trapping moisture in the joint!

Here are some reasons why you should seal your concrete joints:

  • Prevent water from seeping under your concrete. This can help prevent soil erosion and eventual voids under the slabs. 
  • Reduce the risk of mold growth on concrete surfaces where water collects in the joints. This makes it easier to clean up mold colonies before they spread throughout.
  • Keep dirt and debris from getting into the joints during a heavy rain.

Book Your Free Inspection Today!

Sealing the expansion joints and control joints for your home or business can prevent water from seeping under your concrete. Water seeping under the material will cause cracks in the concrete. This can cause unwanted surface issues with the concrete, potentially allowing water to leak into your home or business. Sealing your joints will also strengthen the surface of your concrete, which leads to other benefits like protecting against termites and mold growth.

Where do you turn for help? We are your local Foundation Support Specialists and are here for all your concrete needs. Contact us today for a free inspection.

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