Massachusetts Plumbers Journeyman Practice Exam

How frequently should expansion joints be provided in a building up to ten stories in height?

1. A. At every branch interval

2. B. Only at the top floor

3. C. At every other branch interval

4. D. None needed for buildings up to ten stories

The correct answer is: C. At every other branch interval

The correct answer, which indicates that expansion joints should be provided at every other branch interval in a building up to ten stories in height, is based on the need to accommodate thermal expansion and contraction of piping systems. Buildings can experience significant variations in temperature that affect materials differently. By placing expansion joints at every other branch interval, you allow for adequate movement in the piping system while preventing undue stress that could result from thermal expansion. This practice ensures that the structural integrity of the building and its plumbing systems are maintained. Additionally, it helps to minimize the risk of leaks or failures in the piping due to excessive strain. This approach balances the need for flexibility in the system with practical considerations for installation and maintenance. It recognizes that while some joints are needed, they should not be placed too frequently, which can lead to higher costs and complexity in the plumbing system.