Plastic and cast iron drain piping (C) Daniel FriedmanGuide to Sound Control in Building Supply & Drain Piping

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Building plumbing system noise control & sound isolation:

This article explains methods and materials used to control plumbing piping & plumbing fixture sound transmission in buildings: how to assure quiet plumbing fixtures, plumbing drains, supply piping, heating piping in buildings.

We explain the difference in noise levels from plastic versus cast iron drain piping, we illustrate the sequence of steps in sound insulation useful for isolating noises a plumbing pipe chase from occupied building spaces, we describe noise sources traced to water supply piping & heating system pipes, and we list other plumbing-related sources of building noise. In a series of photo-illustrations we discuss plumbing drain pipe chase insulation & fire safety.

We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.

How to Control Plumbing Noise in buildings

Plumbing chase after foam insulation (C) Daniel Friedman Eric Galow Galow Homes

This article series discusses noise and sound control in buildings, and includes excerpts or adaptations from Best Practices Guide to Residential Construction, by Steven Bliss, courtesy of Wiley & Sons. The page top photo shows our client commenting on a mix of plastic (more noisy) and cast iron (more quiet) drain piping in a building basement where renovations and conversion to occupied space were planned.

Plumbing drain & pipe chase noise control photo 1 - pipe chase construction: at left you can see a horizontal plumbing chase running beneath a floor above.

In typical indoor construction the builder might simply install drywall over the chase framing structure to enclose the supply and drain piping.

The result will be significant noise transmission into the room below, particularly when plastic drain piping has been used, such as the black ABS drain shown in our photo - courtesy Galow Homes [3]. [Click to enlarge].

Other noise and sound diagnosis and control articles are found at NOISE / SOUND DIAGNOSIS & CURE.

Plumbing chase after foam insulation (C) Daniel Friedman Eric Galow Galow Homes

Plumbing chase noise control photo 2 - insulate wall or ceiling penetrations: at left you will see the orange foam insulation that was sprayed to seal the plumbing drain piping where it penetrates an interior wall.

The foam product selected here was chosen for its fire resistance to comply with local building codes.

We divide plumbing drain and fixture noises into two groups:

  1. Plumbing defect noises associated with plumbing system problems or defects whose identification and diagnosis is discussed at our complete list of various plumbing system noise
    See PLUMBING NOISE CHECKLIST for just that - a list of plumbing noise sources

    We explain how to diagnose plumbing drain noises at PLUMBING DRAIN NOISE DIAGNOSIS
    at PLUMBING DRAIN NOISE REPAIR we explain how to correct these disturbances.
  2. Normal (but annoying) plumbing system noises that will be corrected by noise transmission control or sound insulation are discussed here at SOUND CONTROL for PLUMBING where we describe controlling the transmission of plumbing noises in buildings and where we give methods for mimizing plumbing noises and sounds.

Normal plumbing drain sounds

Plumbing chase after foam insulation (C) Daniel Friedman Eric Galow Galow Homes

Plumbing chase noise control photo 3 - complete plumbing pipe chase insulation: as you can see in our photo at left, we completed insulating the pipe chase with spray foam insulation during building wall and ceiling insulation installation.

While thermal insulation was not required between this room and the occupied space above - for heating or cooling purposes, the cost of including the spray foam insulation in this area was low when contracted as part of a building-wide insulation job.

Insulating here provided excellent sound insulation and also improved the thermal performance and temperature consistency in both this room and in the floor above.

As we stated at PLUMBING DRAIN NOISE DIAGNOSIS, Hearing the sound of running water in a building drain is not likely to indicate a problem with the drain system itself. In older buildings where cast iron and steel drain pipes were used, not much sound normally is heard: even the sound of running water, say when a shower is running or when a toilet was flushed.

But in a more modern structure that uses plastic or copper drain piping these materials can transmit the sound of running water to the building interior. Builders can reduce sound transmission from plumbing lines by enclosing them in insulated chaseways.

We have also found cases in pipes in a building transmit sounds from one area of the building to another. We've also found that electromagnetic fields generated in a building, say by a bank of electric meters located in one area, can be transmitted to other building areas through metal piping.

Plumbing Noise & Sound Transmission Sources & Control

Noisy plastic drain waste vent piping (C) Daniel Friedman

As described in the book, Best Practices Guide to Residential Construction Chapter 5, Interior Finish:

One of the most common noise complaints in single-family construction is the sound of water gushing through PVC waste pipes.

The best solution, short of using cast iron, is to box in the pipes and fill the cavity with fiberglass insulation. Then enclose the cavity with one or two layers of drywall.

Plumbing chase noise control photo 4: Our photo (left) shows a different building in which the plastic drain waste piping was routed through a basement that was being finished and to be used as offices. This drain was a subject of recurrent noise complaints in the building.

The leak stains at the ceiling needed to be investigated and the source corrected before this piping run was enclosed in a heavily insulated drywall pipe chase to minimize sound transmission from the upstairs plumbing fixtures into the lower level offices.

Noises from water supply piping & hot water heating piping

Copper piping at basement boiler zone valve (C) Daniel Friedman

Continuing from from Best Practices Guide to Residential Construction:

Water supply and heating pipes can also radiate noise through the framing if there is rigid contact between pipes and framing or finish materials. This can be a particular problem when heating pipes expand and contract. To avoid these problems, make sure pipe runs are not tight against framing.

While special non hardening acoustical sealants are often specified in commercial work, any high-quality sealant that remains flexible can be effective in blocking sound transmission. Butyl, silicone, and urethane caulk can all be used.

To prevent sound leaks, use sealant around electrical boxes, plumbing penetrations, and any other penetrations in the wall or ceiling surface.

see Acoustical Sealant for Sound Control for additional details.

Other sources of noises associated with water or heating piping in buildings

Heating baseboard (C) Daniel Friedman

-- Adapted with permission from Best Practices Guide to Residential Construction. Additional text adapted with permission from The Home Reference Book

Plumbing Noise Articles


Continue reading at PLUMBING SUPPLY PIPE NOISE or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.

Or see SOUND CONTROL in buildings.

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