I have seen some architectural drawings where joints in masonry walls are called control joints. Other architects have called them expansion joints. Do both terms mean the same thing?
No, the terms are not interchangeable. Control joints are designed to control shrinkage or other cracking where relief of masonry expansion is not required. These joints are generally used in concrete masonry walls and stucco. Expansion joints, on the other hand, should be used wherever the joints need to control both expansion and contraction. Because clay masonry undergoes permanent expansion, joints in clay masonry walls should typically be expansion joints.