Expansion joint covers are crucial components in buildings and structures designed to accommodate movement caused by seismic activity, thermal expansion, and other factors. Did you know that a major expansion joint failure issue comes only from incorrectly installing the joint? Installing the joint is not as easy as you think and causes major and expensive problems along the line if not done properly.
In this guide, we'll walk you through the step-by-step process of properly installing expansion joint covers, addressing key considerations along the way.
1. Understanding Expansion Joint Sizing: Before installation, it's crucial to properly size expansion joints to accommodate anticipated movement. Factors such as building materials, temperature variations, and seismic activity should be considered. Consultation with structural engineers or our industry experts can help determine the appropriate sizing for expansion joints in your specific application.
Movement can be shown in the following ways:
as an overall movement
as a percentage of the expansion joint width
or more usually as a +/- movement.
Example 1:
A 50mm nominal expansion joint with an anticipated expansion and contraction of 25mm could be shown in the following way:
50mm +/- 25mm
50mm with a total movement of 50mm
50mm +/- 50%
Pro Tip: When the engineer tells you the joint width, we recommend asking them for the minimum and maximum dimensions at full movement.
2. Installation of Expansion Joint Covers: The installation process of expansion joint covers typically involves several steps:
Block out and surface preparation: Ensure that a proper block out is provided (the area where the joint will sit) when the concrete is being poured and the substrate is clean, dry, and free of any debris or contaminants.
Positioning of Joint Covers: Place the expansion joint covers in their designated locations according to the approved plans and specifications.
Attachment: Secure the joint covers to the substrate using appropriate fasteners or adhesive methods, ensuring a snug fit.
Sealing: Apply sealant around the perimeter of the joint covers to prevent water infiltration and ensure a watertight seal.
Testing: Conduct a thorough inspection of the installed joint covers to verify proper alignment, attachment, and sealing. You can request a site visit from our specialist, and we can arrange one on-site.
Consider floor and wall clearences based on the type of the cover and how it operates.
3. Placement of Expansion Joints: Expansion joints should be strategically placed in areas prone to movement, such as transitions between different building materials, changes in elevation, and structural discontinuities. Proper placement of expansion joints helps to minimize stress on building components and prevent damage due to movement.
4. Installation of Expansion Joints in Concrete: When installing expansion joints in concrete structures, the following steps are typically followed:
Prep: Remove loose particles and weak concrete to ensure sound concrete substrate. Spalls, chipped edges and uneven surfaces must be repaired using suitable patching material and proper patching geometry and techniques. Joint faces must be parallel. Joints must have an unobstructed depth greater than or equal to the full depth of the largest material supplied plus 1/2-inch (6mm).
Dry all wet surfaces. NOTE: If a flame is used to dry substrates, this will leave carbon on the substrate and cause bond failure. Grind and clean the surfaces to remove carbon.
Insertion: Place the expansion joint material into the cut joints, ensuring proper alignment and depth.
Sealing: Apply sealant to the edges of the expansion joint material to prevent water infiltration and maintain a watertight seal.
Finishing: Smooth the surface of the sealant to create a uniform appearance and improve durability.