FAQs

An expansion joint is a gap or opening within a structure to absorb movement of the structure due to the following: a. Thermal - Caused by temperature variation within the structure, mostly horizontal movement. b. Seismic - Caused by earth tremors, movement may be vertical, horizontal or shear movement. c. Wind Load - Caused by high wind forcing the structure to sway.

An expansion joint system is an assembly designed to safely absorb the movement by expansion and contraction of various construction materials (e.g. concrete slab on the ground, suspended slab, wall etc.) and to allow traffic (pedestrians, trolleys, vehicles etc) to pass safely over the surface.

Normal width is a gap between slabs or walls at a median temperature approx 20° Celsius. In some cases this may be different, due to thermal or shrinkage conditions. Concrete must be fully cured to determine the normal / installation gap width.

Movement range is an anticipated range of thermal movement or seismic movement. For Example :- 1. A 100mm normal gap or installation gap is anticipated to have a range of horizontal movement of + 20mm or – 20mm could also be indicated as 100mm +/- 20mm, meaning the gap closes to minimum of 80mm and opens to a maximum of 120mm. 2. Seismic joints will typically have a movement range of 100mm +/- 50mm to +/-100mm.

Like most other architectural products a joint system should be select based on the following: 7.1. Location of joint: Interior or Exterior 7.2. Where is the joint being installed: Floor Wall Ceiling Roof 7.3. Movement range (your structual or design engineer can provide this information): Thermal Seismic 7.4. Expected Loads (for floor joints only): Pedestrians Trolleys Vehicles Forklifts Skateboards Roller Blades Cleaning Machines Is the joint is subject to point loading? If unsure of loads, your structural or design engineer can provide this information.