1. Floor or Wall Assembly — Min 4-1/2 in. (114 mm) thick reinforced lightweight or normal weight (100-150 pcf or 1600-2400 kg/m³) concrete. Floor may also be constructed of any min 6 in. (152 mm) thick UL Classified hollow core Precast Concrete Units*. When precast concrete units are used, the max diam of opening is 7 in. (178 mm). Wall may also be constructed of any UL Classified Concrete Blocks*. Max diam of opening is 8-1/2 in. (216 mm).

See Concrete Blocks (CAZT) and Precast Concrete Units (CFTV) category in the Fire Resistance Directory for names of manufacturers.

2. Metallic Sleeve — (Optional) - Nom 8 in. (203 mm) diam (or smaller) Schedule 10 (or heavier) steel sleeve cast or grouted into floor or wall assembly, flush with floor or wall surfaces.

3. Steel Duct — Nom 6 in. (152 mm) diam (or smaller) No. 28 gauge (or heavier) steel HVAC duct to be installed either concentrically or eccentrically within the firestop system. The annular space between duct and periphery of opening shall be min 0 in. (0 mm, point contact) to max 1-7/8 in. (48 mm). Duct to be rigidly supported on both sides of floor or wall assembly.

4. Firestop System — The firestop system shall consist of the following:

A. Packing Material — Min 2 in. (51 mm) thickness of mineral wool batt insulation firmly packed into opening as a permanent form. When min annular space between duct and edge of opening is 5/8 in. (16 mm), polyethylene backer rod may be used. Packing material to be recessed from bottom or top of floor or from one surface of solid concrete wall as required to accommodate the required thickness of fill material. In floors constructed of hollow core precast concrete units, packing material recessed from bottom of floor or from both sides of floor. In walls constructed of concrete blocks, packing material recessed from both sides of wall as required to accommodate the required thickness of fill material.

B. Fill, Void or Cavity Material* - Sealant — Min 3/4 in. (19 mm) thickness of fill material applied within the annulus, flush with bottom or top surface of floor or with one surface of solid concrete wall. In floors constructed of hollow core precast concrete units, fill material installed flush with bottom surface of floor or with both surfaces of floor. In walls constructed of concrete blocks, fill material installed symmetrically on both sides of wall.

RECTORSEAL — FlameSafe® FS900+ Sealant, Metacaulk MC 150+ and Biostop BF 150+