Which of the following is a type of gypsum lath?

Which of the following is a type of gypsum lath?

• A. Perforated
• B. Lead-backed
• C. Type X
• D. All of the above

Answer: (D)

Gypsum lath serves as a plaster base and comes in several forms to meet different performance needs. Perforated gypsum lath has punched holes that let plaster key into the base and help it grip, while also reducing weight. Lead-backed gypsum lath uses a sheet of lead behind the gypsum core to act as a moisture barrier and chemical shield in damp areas, improving durability of the plaster in those locations. Type X gypsum lath refers to gypsum lath that includes the fire-resistance characteristics of Type X board, providing enhanced fire performance in the wall assembly. Because all of these are gypsum-based plaster bases, they all count as gypsum lath types, so all of the above apply. In practice, you’d select perforated for standard plaster on wood or metal framing, Type X in fire-rated walls, and lead-backed where moisture resistance is needed in older or specialized installations.

Gypsum lath serves as a plaster base and comes in several forms to meet different performance needs. Perforated gypsum lath has punched holes that let plaster key into the base and help it grip, while also reducing weight. Lead-backed gypsum lath uses a sheet of lead behind the gypsum core to act as a moisture barrier and chemical shield in damp areas, improving durability of the plaster in those locations. Type X gypsum lath refers to gypsum lath that includes the fire-resistance characteristics of Type X board, providing enhanced fire performance in the wall assembly. Because all of these are gypsum-based plaster bases, they all count as gypsum lath types, so all of the above apply. In practice, you’d select perforated for standard plaster on wood or metal framing, Type X in fire-rated walls, and lead-backed where moisture resistance is needed in older or specialized installations.