I often get asked about why concrete cracks and how to prevent cracks in concrete construction. Generally speaking, concrete is going to do two things: 1) get very hard and 2) crack. Installation of control joints provides a location for the concrete to crack, thus “controlling” where the concrete cracks. Constructed joints are much more aesthetically pleasing than a crack. Check out this good article from PCA for more on why, when and how to use control joints. – Jason Savage, DTC Civil Construction Instructor
