CC-1000_2018

CC-1000 Companion Guidance (1-2018) CC-1000 Companion Guidance CG Page of 12 Informational 6 5.5.2 c) Sands, fine gravels and soils Advisory — Hydraulic conductivity is required. Sands that contain more than 10% fine sand, silt and clay are not considered gas permeable for the purposes of CC-1000. 5.5.3 Sand, fine gravel and soils If permeability requirements for small grain aggregates are met: These options need geotextile matting or perforated pipe that provides evenly distributed distances for air inlet openings in the matting or the perforations in pipe such as strips or loops not more than 20 feet (6 m) apart. 5.5.4 Other gravel or crushed stone Larger stones such as 1, 2, 3, 4 and 367 as classified by ASTM C33 can be exceedingly effective but require care that structural integrity of slabs and membranes are not compromised. 5.5.5 Depth of gas permeable aggregates Exceeding a 4” depth is encouraged. Less than 4” depth is only allowed at edges where grading machinery cannot maneuver. ! 5.6 Duct sizes above and within the gas permeable layer 5.6.1 Primary and main trunk sizing 5.6.2 Secondary trunks and branches 5.6.3 All duct sizing 5.6.4 Size changes 5.6.5 Transitions 5.6.6 Airflow resistance within Inlet trunk networks + ! ! • ! Primary and Main trunk sizing is determined by plenum size. • ! Generally, all ducts must not be smaller than 3-inch (7.6 cm) ID pipe. • ! Primary and Main trunk size not reduced along the path to exhaust. • ! Pipe size and lengths must be designed to avoid excessive airflow resistance at the furthest distances away from the exhaust location . ! + Exhaust location Examples of ducting terminology