Expansion Joints vs Construction Joints: What Is the Difference?

Not all joints in concrete floors serve the same purpose. Expansion joints accommodate movement, construction joints occur where concrete pours meet, and saw-cut joints are designed to manage shrinkage. Treating every joint as a simple crack can lead to premature failure.

Identify the joint from the slab design and the conditions on site before deciding how to treat it. Its appearance alone may not reveal its purpose. Construction joints mark a break between concrete pours, while movement joints are intended to accommodate movement; the treatment must respect that function.

Inspect the joint edges, sealant, wheel traffic and any differential level between slab panels. A surface repair should restore damaged edges without unintentionally locking a joint that needs to move. Coordinate joint detailing with the resin flooring specification and any structural advice. Keep a record of joint locations so future resurfacing does not conceal important movement details.