How to Guide

114
Plastics Technical Manual
Selection of Materials For Sanitary and
Storm Drainage
Engineers and designers today have a number of materials
from which to choose as they design sanitary and storm
drainage systems for residential and commercial projects.
Due to its exceptional strength and combination of being
non-combustible and extremely quiet, cast iron soil pipe is
averypopularchoiceforcommercialconstruction.Upscale
homes often feature cast iron stacks combined with plastic
used for lavs, showers and tubs for a system Charlotte Pipe
callsa“QuietHouse
®
”design.PVCandABSDWVsystems
are allowed under all of the major national plumbing codes
unless restricted by local or state amendment and are very
popular as well.
Charlotte Pipe manufactures ABS cellular (foam) core pipe
conforming to ASTM F 628 as well as PVC pipe in both
solid wall and cellular core types. PVC solid wall meets the
requirementsofASTMD1785andD2665,andPVCcel-
lularcorepipeconformstoASTMF891.Alloftheseplastic
pipe systems are allowed for sanitary and storm drainage
bothaboveandbelowgradeintheUniformPlumbingCode
(UPC),theInternationalPlumbingCode(IPC),theNational
Standard Plumbing Code (NSPC) and most local or state
variationsthereof.None of these national model codesdif-
ferentiate between residential or commercial uses of these
plastic systems or otherwise restrict the use of any of these
systems to any specific class of construction. All of the
systems can be installed below grade, under slab and above
grade in most areas except those classied as “return air
plenums.”
Solid wall pipe is just as the name implies: solid PVC ma-
terial throughout the entire pipe wall. Cellular core pipe
is manufactured using a unique co-extrusion process that
produces pipe with a thin solid inner layer and outer layer
with a foam core between these walls. Foam core pipe has
the exact same dimensions as solid wall, yet is lighter and
less expensive. Noise transmission is a function of density
so while cast iron is by far the quietest material, PVC solid
wall would be somewhat less noisy than either PVC or ABS
cellularcorepipe.Whilebotharesuitableforburialatmost
depths and common soil types, solid wall pipe is somewhat
more“robust”andhasahigherpipestiffness,particularly
insizes6”andsmaller.BothASTMF628andF891have
the following limitation; Appendix X3, Installation, para-
graphX3.1:maximumaggregatesizeshallbelimitedto1/2
in. (13 mm) for angular and 3/4 in. (19 mm)for rounded
particles. This statement is signicant as ASTM  D 2321
allows aggregate and stone that pass through 1
1
⁄ 2 ” sieve.
PVC is classified as a flexible piping system, and as such it
is dependant upon proper bedding and backfill for its ability
to withstand Earth and live loads. Therefore, all plastic pipe
mustbeinstalledbelowgradeinaccordancewithASTMD
2321. Cellular core pipe of any type is designed for drainage
only, carries no pressure rating and Charlotte Pipe marks
eachpiecewiththeprintline“NotforPressure.”PVCsolid
wallpipeis“dualmarked”andmeetstheASTMstandards
for both pressure and drainage pipe.
Manydesignersallowtheuseofcellularcorepipeonresi-
dential or light commercial projects and require the use of
solid wall PVC or cast iron on commercial projects such as
institutions, schools, restaurants, hospitals etc. Charlotte
Pipe recommends that cellular core PVC pipe be installed in
commercialapplicationswithcaution.Undergroundinstal-
lations should be in strict conformance to ASTM D 2321.
Ultimatelytheengineer, designer,developerorownermust
evaluate the requirements of each project and specify the
products they feel best suit their design criteria.
Engineered Applications
Over the past few years many new innovations have been
introduced to the industry including siphonic roof drainage,
sovent, air admittance devices and other products. Some of
these products do not conform to existing standards or to the
requirements of the model plumbing codes. Rather, they are
designed into the system by engineers and approved as an
alternate material within the code.
Charlotte Pipe and Foundry manufactures pipe and fitting
systemsthatconformtopublishedASTMandCastIronSoil
Pipe Institute standards. Products are warranted to conform
to the requirements of applicable standards when used for
the applications defined within these standards. Charlotte
Pipe and Foundry will not accept liability for applications
that do not conform to the standards to which we manufac-
ture.
QuietHouseisaregisteredtrademarkofCharlottePipeandFoundryCompany.
SPECIAL CONSIDERATIONS
Material Selection, Special
System Design and
Engineering Considerations
To reduce the risk of death or serious injury from an explo-
sion, collapse or projectile hazard and to reduce the risk of
property damage from a system failure:
• Always follow the warnings and procedures provided in
this manual.
• Only use PVC/ABS/CPVC pipe and fitting for the
conveyance of fluids as defined within the applicable
ASTM standards.
• Never use PVC/ABS/CPVC pipe and fittings for the
conveyance of gasses.
• Never use PVC/ABS/CPVC pipe or fittings in structural
application or in any load-bearing applications.
• Never strike the pipe or fittings or drive them into the
ground or into any other hard substance.