Underground Cellular Glass installations should be protected with?

• A. Plastic wrap
• B. Concrete block
• C. Pitt wrap
• D. Foam board

Answer: (C)

Underground installations of cellular glass require a durable outer layer that stops moisture from reaching the insulation and shields it from soil abrasion during burial. Pitt wrap is a purpose-made protective wrap designed for buried insulation; it provides a continuous moisture barrier and protects the surfaces and joints as backfilling occurs, helping preserve the insulation’s performance over time. Plastic wrap lacks the durability and sealing needed for long-term burial. Concrete block isn’t used as a protective wrap around buried insulation, and foam board is an insulation material rather than a protective jacket for the insulation system.