Which items are included in Gypsum Plaster Installation?

• A. Wood laths or metal laths; galvanized screws; grounds layer; coat 1 scratch coat; coat 2 brown coat; coat 3 finish coat
• B. Wood laths only; no coats; finish coat only
• C. Plastic laths; single coat
• D. Titanium laths; scratch coat only

Answer: (A)

Gypsum plaster installation relies on a solid substrate, proper fasteners, a bonding base, and multiple coating layers to build a durable, smooth finish. You start with laths (wood or metal) as the backing for the plaster. These laths must be securely attached to the framing using galvanized screws to prevent corrosion and ensure the plaster has a stable grip. A grounds layer is then applied as a bonding base so the plaster adheres well to the lath. After that, the plaster is built up in coats: a scratch coat to roughen the surface and provide key for the next layer, a brown coat to add thickness and strength, and a finish coat to create the final smooth surface. This sequence and set of materials ensure proper adhesion, durability, and finish. Other options omit coats or use nonstandard lath materials, which do not fit typical gypsum plaster installations.