Study for the HVAC Journeyman Exam with our comprehensive resources. Get familiar with the exam format through engaging quizzes, flashcards, and multiple-choice questions designed to enhance your knowledge. Prepare effectively and confidently for your HVAC journey!

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

Practice this question and more.


What is the minimum requirement for metal ducts installed in or under a concrete slab?

  1. Insulated

  2. Protected from damage

  3. Encased in at least 2 inches of sand

  4. Encased in at least 2 inches of concrete

The correct answer is: Encased in at least 2 inches of sand

The minimum requirement for metal ducts installed in or under a concrete slab is that they must be encased in at least 2 inches of sand. This is to ensure that the metal ducts are protected from potential damage caused by the surrounding concrete and any shifting or settling that might occur over time. Sand provides a cushioning effect, preventing direct contact between the metal ducts and the concrete, which could lead to corrosion or physical damage to the ducts. Encasing ducts in sand also helps to maintain the integrity of the duct system, ensuring efficient operation without the risk of leaks or blockages due to constriction or impact from the concrete. While insulation and other protective measures are important for HVAC systems, in the context of installation under a concrete slab, proper protective encasement in sand meets the specific need for safeguarding ductwork in potentially vulnerable environments. This practice aligns with industry codes and standards to ensure the longevity and efficiency of the HVAC system.