The Hard Coat System process is made up of 2-ply, 30-weight black paper with 20-gauge metal lath stapled and then nailed over the black paper. All edges are outlaid in a metal ”J” channel; the standard is a 3/8" thick coat. Fiber meshed concrete is mixed with sand in a mixer and then applied over lath to form a base coat, or as it is referred to, as a "brown coat." A seven-day curing period is then given for cracking and expansion. At that point, a final color acrylic coat will be applied for a finished product. All doors and windows are left with a 3/8" gap for caulking purposes.
These products are made by El Rey™, Omega™, La Habra™ and Dryvit™.