CC-1000_2018

Soil Gas Control Systems ANSI/AARST CC-1000 2018 in New Construction of Buildings 15 8.4.2.2 Where it is likely that condensation will occur on the exterior surface of duct piping to the extent damage would occur to adjacent building materials, duct piping shall be provided with insulation having an external vapor barrier and an R-value of not less than 1.8. 8.5 Pipe support. Above ground piping shall be supported by the structure of the building using hangers or strapping designed for piping support. Supports for plastic horizontal piping shall be installed at intervals not exceeding 4 feet (1.2 m) and supports for vertical piping shall be installed at intervals not exceeding 10 feet (3 m). Support locations and pipe routing shall inhibit both lateral and vertical movement of duct piping that can result in compromised pipe joint connections and avoid of locations that are susceptible to blunt force impact. Duct piping and fans shall be mounted and secured in a manner that minimizes transfer of vibration to the structural framing and finishes of the building. 8.6 Equivalent length—vent pipe pressure loss From its connection at the soil (i.e., gas permeable layer ) to the point of exhaust at the roof, exhaust vent piping with smooth inner surfaces shall be nominally no more than these equivalent lengths : a) 75 feet (23 m) for 3-inch (7.6 cm) exhaust piping; b) 150 feet (46 m) for 4-inch (10.2 cm) exhaust piping; c) 440 feet (134 m) for 6-inch (15.2 cm) exhaust piping. The calculated equivalent length for duct pipe materials that do not have smooth inner surfaces shall be nominally reduced with a goal of no less than 1 water column inch pressure loss, or reduced by 25%. 8.7 Piping materials The exhaust vent piping that extends from the soil gas collection plenum to the point of exhaust shall be rigid, non-perforated pipe that is suitable for drainage of condensate water, which occurs naturally and consistently within piping. 8.7.1 PVC piping PVC pipe shall comply with ASTM D2665, F891 or F1488. The pipe wall thickness shall be Schedule 40. 8.7.2 Alternative materials Alternative materials specified in codes for “Subslab Soil Exhaust Systems” 10 shall be permitted including ABS plastic pipe and iron, steel, copper or other materials permissible by code. Alternative pipe materials that do not meet durability specifications in 10 As a point of reference for alternative piping, see the International Mechanical Code (IMC) Section 512.2 (as published by the International Code Council). ASTM D1785 for Schedule 40 shal l be permitted as an alternative material for use only w hen within enclosed wall cavities. Support for above ground alternative duct pipe materials shall be in accordance with code 11 and manufacturer specifications. 8.8 Joints Plastic pipe joints shall be solvent welded. 8.8.1 PVC plastic pipe joints The joint surfaces for PVC plastic pipe and fittings to be solvent-welded shall be prepared with a primer conforming to ASTM F656. P VC plastic pipe joints shall be solvent-welded in accordance with the pipe manufacturer’s instructions with solvent cement conforming to ASTM D 2564. 8.8.2 Alternative pipe materials Alternative pipe materials identified in Section 8.7.2 (e.g., ABS plastic, iron, steel and copper) shall be joined in accordance with the pipe manufacturer’s instructions and as required by code. 8.8.3 Flexible coupling disconnects Where disassembly may be required in the future for maintenance purposes, the disconnect shall consist of two unconnected portions of pipe joined with a flexible coupling that complies with ASTM D5926, ASTM C1173 or an equivalent method. Allowable uses for a flexible coupling disconnect shall include: a) where joining duct piping materials that are incompatible for solvent welding; b) at locations where physical constraints inhibit the ability to join duct pipe materials by means of a solvent weld; c) at locations allowed by code to provide temporary access to areas requiring maintenance or inspection, such as access to mechanical equipment by removal and airtight replacement of duct pipe sections; and d) to minimize noise by breaking the direct transfer of fan vibration energy to other duct piping. 8.9 Provision for ASD fan(s). 8.9.1 Fan location A location for each ASD fan shall be identified. The location designated for ASD fans shall be only outdoors, in attics or in gara ges that meet ventilation requirements of Section 4.8 . T he location for ASD fans shall only be on vertical exhaust vent piping. Exhaust vent piping from the designated ASD fan location(s) to the termination point of exhaust pipe outside the building shall not be located inside or below conditioned or occupiable space. 11 As a point of reference for alternative piping support, see the International Mechanical Code (IMC) Section 303 (as published by the International Code Council).