How to Guide

115
Unstable Soil
Burial of pipe under slab in soils that are unstable is often
accomplished by suspending the piping systems from struc-
tural slabs. The use of plastic pipe in such installations must
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specifically not permitted for these applications.
Using Plastics in Multi-Story Construc-
tion
Incorporating plastic piping systems into multi-story con-
struction raises special design considerations. Charlotte Pipe
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or other applicable product-based standard, not for any par-
ticular system design.
Products and materials selected for use in multi-story con-
struction (four floors and up) must conform to all applicable
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or specification should be made by an architect, engineer,
contractor, or other licensed professional. This must include
specification of a code-compliant, chemically compatible
firestop system with an appropriate service life, which must
be properly installed and inspected for conformance to build-
ing, plumbing and fire codes by the responsible governmental
authority.
In selecting products and material for multi-story construc-
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iron soil pipe products, which are an excellent choice for
many multi-story applications. Charlotte Pipe recommends
SPECIAL CONSIDERATIONS
Combustion Gas Venting
Failure to properly vent combustion gas may result in
serious injury or death from carbon monoxide.
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appliance manufacturer's installation instructions to
vent appliances.
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tic pipe, including CPVC pipe, change over time. Visually,
this means that the pipe may experience color variations. The
temperature of the water running through the pipe often de-
termines the degree of variation, with hot water causing a
more noticeable change. Such color variations, however, do
not indicate that the performance of the pipe has been com-
promised. The pressure bearing capabilities of CPVC pipe, in
fact, actually increase as the pipe ages to help ensure a reli-
able, long-term performance.
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system. But since an installed system has little opportunity
to sustain impact, this change has little to no effect. It does
mean, however, that if a cut-in is necessary as a result of a
modification to the line or the addition of a fixture, addition-
al care should be taken to prevent the system from sustaining
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installing new pipe, its use can compress the pipe and cause
end cracks on aged pipe. For this reason, a ratchet cutter
should not be used on aged CPVC pipe. Even if the cracks are
not visible, they can eventually propagate through the fitting
and cause a leak.
I suggest using either a wheel-type cutter or fine-tooth saw
when performing a cut-in procedure. Once the pipe is cut,
continue with standard installation procedures, including
beveling the pipe and solvent cementing the fitting. Keep in
mind that if the area is wet as a result of water being inside
the line, you need to add to the cure time typically required.
In some cases, the required cure time may be three times as
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as possible.
Repairs or Modifications to Existing CPVC CTS Systems
(Reprinted from FBC Plumbing Connections, Issue 29, 4Q 2009, written by Steve
Manis, Technical Manager)
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construction.
Using Plastics for Combustion Gas
Venting
Charlotte Pipe recommends that inquiries about the suit-
ability of plastic piping systems for venting combustion gas-
ses should be directed to the manufacturer of the water or
space heating equipment being installed. As stated in the
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503.4.1.1:
Plastic Pipe and ttings used to vent appliances shall be
installed in accordance with the appliance manufacturer’s
installation instructions.
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plastic pipe and fittings that Charlotte Pipe manufactures
include the following note: This standard specification does
not include requirements for pipe and fittings intended
to be used to vent combustion gases.