Expansion joints are important in concrete driveways because they allow for the natural expansion and contraction of concrete due to changes in temperature and moisture levels. When concrete expands and contracts, it can cause cracking and damage to the surface if it is not able to move freely.
Experienced concreters know that expansion joints provide a space for the concrete surface to expand and contract without causing damage to the driveway. Without these joints, the concrete could crack or even lift up, causing tripping hazards and other safety issues.
For this blog, we’ll take a closer look at expansion joints for concrete driveways to better understand their use.
What are the Types of Expansion Joints?
Different types of expansion joints can be added to concrete surfaces. These are the following:
- Saw-cut joint: One type of expansion joint is the saw-cut joint, which is created by using a saw to cut a groove into the concrete. This joint can be used to control cracking and allow for concrete movement.
- Preformed joint: Another type of expansion joint is the preformed joint, which is made from materials such as plastic, rubber, or metal. These joints are typically placed before the concrete is poured and allow for movement in the concrete.
- Sealant joint: Sealant joints are created by filling a joint with a sealant material, such as silicone or polyurethane. These joints are flexible and can be used to prevent water from penetrating the concrete.
Where Are Expansion Joints Placed?
Expansion joints are typically placed at intervals of 2 to 3 metres, and the exact spacing will depend on factors such as the climate and the size of the driveway.
It is important to consider the following factors to determine the optimal placement of expansion joints:
- Temperature changes: Driveways in areas with significant temperature changes will require more frequent expansion joints to allow for concrete movement.
- Length of the driveway: Longer driveways will require more expansion joints to allow for the movement of the concrete slabs
- Subgrade conditions: Driveways that are built on unstable or expansive soil may require more frequent expansion joints to prevent cracking and damage.
How Are Expansion Joints Installed?
The following steps should be taken to install expansion joints:
- Determine the optimal placement and spacing of the joints based on the factors discussed in the previous section.
- Prepare the area where the joints will be installed by cleaning and removing any debris or loose material.
- Install the joints according to the manufacturer’s instructions, ensuring that they are flush with the surface of the concrete.
- Seal the joints with a flexible sealant material to prevent water from penetrating the concrete.
It is important to note that the installation of expansion joints should be performed by a qualified professional with experience in concrete driveway installation.