- Author
- Winter, F. | Galowin, L.
- Title
- Experimental Evaluation of Circulation Loop Drain and Vent Plumbing Modifications for Building Rehabilitation.
- Coporate
- National Bureau of Standards, Washington, DC
- Report
- NBSIR 82-2602, December 1982,
- Distribution
- Available from National Technical Information Service
- Keywords
- buildings; renovating; plumbing; piping systems; vents; exhaust pipes; air flow; performance evaluation | rehabilitation
- Abstract
- Rehabilitation or modernization of existing buildings frequently imposes increased loads on the plumbing water supply and drainage system. The requirement for venting in U.S. practice is intended to prevent trap seal loss from exceeding values prescribed in model plumbing codes. The vent piping in older buildings may be marginal for retrofit under code requirements for new construction with the same or increased numbers of fixtures and devices installed into the plumbing system. An experimental laboratory investigation of a circulation loop modification to a drain-waste-vent (DWV) system was conducted to determine the change in performance. An experimental evaluation of the performance of the modified system and a conventional system were undertaken for a variety of simulated wastewater-loads with various plumbing fixtures and multi-story soil stack loads. The performance parameters considered were trap seal failures, backflow, and the siphonic action of the water closets. Also, the dynamic responses to pressure excursions and air flow rates in the branches were measured. Both systems were tested to the limiting condition for single-stack performance over a range of air flow rates into the soil and vent stack.