PVS Installation and Information Listed PVS Underground Installation Guidelines 1) Dig trenches in accordance to plans and specifications; confirm the location of any existing utility lines or piping. 2) Allow 3 inches of encasement clearance around duct for backfill of drainage material or concrete. Structural reinforcement or a slab must be in place where point loading may occur. 3) Pitch all piping systems back towards the utility room for proper drainage. Wrapping duct in a vapor barrier is recommended to prevent surface water leaching into the duct system from natural drainage. 4) Hold-down straps and pipe reinforcements are recommended for large diameter or concrete encased systems. 5) Fasten joints with metal screws or pop rivets used at 6” intervals with a minimum of three per joint, then seal with approved sealer or tape. 6) If the PVC coating has been damaged during installation, PVC paint is available to touch up any scratches that may have occurred. 7) Care should be taken to not pour or back-fill directly onto the piping system. The pour or back-fill can now be completed, with care being used as the concrete or back-fill is placed over the top of the duct, no powered vibrator should be used in the compaction of the concrete or back-fill. For soil encasement systems, no external loads should be allowed at any time unless previous calculations allow for these load conditions. The duct, encased either in concrete or buried directly below a concrete slab, is installed above the original line of undisturbed soil and above the water table. Encasing the duct in concrete with porous fill beneath is the best way to install Spiral vinyl-coated duct. An optional vapor barrier can be place between the slab and the fill. These are only basic guidelines; you must check your local building codes for more specific installation instructions. PVS Information PVS Spiral pipe is UL listed and manufactured from prime hot dipped galvanized steel coated with polyvinyl chloride material, with an outside thickness of 4-mil and inside 1-mil, standard. This is reversible for special purposes. For extreme duty applications a 4x4 coating is applied. External corrugations are standard for 14” diameters and over for underground applications. Standard gauges are 4” to 16” / 24 gauge, 17” to 24” / 22 gauge, 26” to 48” / 20 gauge. Our PVS coated class I duct has a temperature range of -40 F to 250 F and should not exceed 3600 fpm with positive and negative pressure limits not in excess of 6 inches water column. For more detailed specifications, visit our website. PVS Compliance data Spiral Manufacturing Co., Inc. PVS products comply with the following codes and industry standards: UL 181 Class I International Mechanical Code – 1996 Section 603 BOCA National Mechanical Code – 1993 ICBO Uniform Mechanical Code – (UMC) 1997 SMACNA Sheet Metal Air Conditioning Contractors National Association