Page 75 - CPVC Fire Sprinkler Products Installation Instructions & Technical Handbook

INSTALLATION 73
Products coming in contact with CPVC systems (for example, insulation) must be chemically compatible. (See Notice located on Page 55, Chemical Compatibility section.)
Batt Insulation Installation Recommendations
The 2007 edition of NFPA 13D, The Standard for the Installation of Sprinkler Systems in One and Two-Family Dwellings and Manufactured Homes, Appendix A.8.3.1 recommends the following guidelines for use of batt insulation:
In areas subject to freezing, care should be taken to cover sprinkler piping completely in unheated attic spaces with insulation. Installation should follow the guidelines of the insulation manufacturer. (Figures A.8.3.1 (a) through (e) show several installation methods that can be considered.)
• A.8.3.1 (a) “It is important that the insulation be installed tight against the joists. In unheated areas, any spaces or voids between the insulation and the joists causes the water in the fire sprinkler piping to freeze.”
• A.8.3.1 (b) “For areas having temperatures of 0°F (-18°C) or lower, an additional batt of insulation covering the joist and the fire sprinkler piping should be used. If this is not done, localized freeze-ups can occur in the sprinkler piping.”
• A.8.3.1 (c) “Boring holes in the joist is one of the methods for locating the fire sprinkler piping in the ceiling. As an alternative, when temperatures 4 are expected to be 0°F (-18°C) or lower, loose pieces of insulation should be stuffed in the bored holes around the piping.”
• A.8.3.1 (d) (e) ”Care should be taken to avoid compressing the insulation. This reduces its R value. To prevent potential freeze-ups of the sprinkler piping, the insulation should be tight against the joists.”
Minimum insulation R value requirements are typically between R19 and R30; however, the minimum requirements must be verified with the authority having jurisdiction.
CUT-IN PROCEDURE FOR SYSTEM MODIFICATION AND REPAIR
At times it may become necessary to make modifications to existing CPVC fire sprinkler systems. Cut-ins can be done safely when the proper procedures are followed. The following procedure has been developed to assure that the modifications are done successfully.
Prior to making cut-ins to existing systems, care should be used to review proper joining procedures and to follow cut-in cure schedules (Tables U, V and W) to ensure system integrity. Several methods can be utilized to tie into an existing system using a socket style tee fitting in combination with the use of socket unions, grooved coupling adapters, and flanges. Regardless of the method used, the following points must be followed to ensure system integrity:
• Using proper tools, the cut-in should be made on the smallest diameter pipe section (that is capable of adequately supplying the system changes) in close proximity to the modification being made. This approach will expedite cure times prior to pressure testing.
• The cut-in connection to the existing system should be made first, prior to proceeding with additional work.
• Existing lines must be drained adequately prior to solvent cementing. Use