Buzz
An expansion joint serves as a filler between slabs of concrete, absorbing pressure from temperature fluctuations, helping prevent cracks from forming. Jung Getty / Getty ImagesMain Points to Remember
- Concrete expansion joints are inserted between slabs to absorb stress caused by temperature shifts, preventing cracks from forming.
- To replace damaged or old joints, you need to remove the old material, clean the joints, apply a bonding adhesive, insert a foam backer rod, and seal everything with self-leveling urethane sealant.
- Ensure the area remains blocked off while the sealant sets, as this is crucial for the proper function of the new joints.
An expansion joint is a material inserted into the spaces between concrete slabs to prevent cracking as the concrete expands and contracts due to temperature fluctuations. This material acts like a shock absorber, relieving the stress from the slab's movements. Over time, however, the expansion joint may lose its effectiveness as it dries out, causing it to no longer absorb stress properly. This is when cracks begin to form in the concrete slabs. At this point, it’s necessary to replace the expansion joints. Follow these steps to replace them yourself.
- Clear the area of any dirt or debris.
- Use a putty knife to dig out and remove all the old material from the joints. Rinse away any remaining debris with a hose.
- Thoroughly clean the joints between the slabs using a wet-dry vacuum.
- Brush a bonding adhesive, usually epoxy, into the joints. This will help the new material adhere to the concrete. Let the adhesive dry for about 10 to 15 minutes, but not longer, as it should remain sticky to the touch, not fully dry.
- Place a foam backer rod into the joint to act as a new shock absorber. Measure the required length and cut the rod to fit. Insert it into the joint with a putty knife, ensuring it’s pushed in securely.
- Seal the joint by applying a generous amount of self-leveling urethane sealant. It’s advisable to wear safety goggles and gloves during this process.
- Block the area off so no one walks on the newly sealed joints until the sealant has fully dried.
[sources: Realtor, Inspectapedia]
