THE POTEET GROUP

Pyrofill Gypsum Concrete is mill formulated and composed of calcined gypsum and wood chips or shavings. It is mixed at the job-site with clean water only and poured in place over permanent formboards. Thermal resistance (R) value is 0.67 per inch. It complies with ASTM C317

Steel sub-purlins vary in size, weight and shape and are selected according to required span and loading. They provide lateral bracing, anchorage against uplift, and restrict deck movement due to temperature change. Sub-purlin spacing accommodates formboard with a slight tolerance for ease of formboard placement. Sub-purlins are spaced approximately 32-5/8 inches o.c. and are welded to the structural framing members. No. 218 Bulb Tee sub-purlins are the only size currently manufactured and are available from The Poteet Group.

Reinforcing mesh for gypsum concrete is one of the following types:

Ø KEYDECK--A galvanized wire mesh, woven with 16-ga. straight wires and 19-ga. diagonal wires.

Ø 48-1214--A galvanized, welded wire mesh with 12-ga. longitudinal wires at 4-inch o.c. and 14-ga. transverse wires at 8-inch o.c.

The effective cross-sectional area of reinforcing mesh placed at 90o to the sub-purlins is 0.026 sq. in. per foot of mesh width. USG neither manufactures nor sells reinforcing mesh.

SHEETROCK Formboard, a rigid gypsum board treated to resist mildew*, and fiberglass formboard are both available. Fire ratings are available with 2-inch gypsum slabs and exposed tees. Ideal for almost every roof deck need, concealed or exposed. Makes economical ceilings for warehouses, light manufacturing buildings, schools--any construction where durability and low cost are desired.

*Although SHEETROCK brand Formboard is treated to resist mildew growth, such growth can occur under adverse conditions.