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Water Supply Piping, Drain Piping, other Building Pipes and Plumbing: piping failures, leaks, and litigation

• Home page for water supply piping information:
  
  SUPPLY PIPING

• Home page for water pipes:
  
  PIPING in BUILDINGS, CLOGS, LEAKS, TYPES

• Home page for drain piping: 
  
  DRAIN & SEWER PIPING

• WATER HEATERS -
  
  a detailed guide to all types of hot water sources, problems, inspection, repair
• WATER PRESSURE LOSS DIAGNOSIS & REPAIR -
  
  how to diagnose and correct poor water pressure in any building
• WATER SOFTENERS & CONDITIONERS -
  
  how to treat hard water to avoid pipe clogging and other water problems

Water Supply Piping, & Drain Piping, Water Supply Equipment, other Building Pipes and Plumbing

The following basic water supply information is adapted with permission from Carson Dunlop Associates Home Reference Book.

• The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assists home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume.
  
  Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
  
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For complete water pressure problem diagnosis

see WATER PRESSURE LOSS DIAGNOSIS & REPAIR and see our water pressure diagnostic table

at WATER PRESSURE PROBLEM DIAGNOSIS TABLE.

Also see WATER HEATER PIPING - how are individual or multiple water heaters hooked-up: how are water heater pipes and heaters cascaded, ganged, in series, in parallel

Public Water Supply Piping Properties, Pressure & Flow Problems

If your water supply is from a municipal supply and there are pressure or flow problems, see MUNICIPAL WATER PRESSURE DIAGNOSIS. Excerpts are below.

Typically, the water mains in residential areas are four inches to 12 inches in diameter, and run several feet below the street level.

Smaller pipes, usually 1/2 inch or 3/4 inch diameter, run from city mains into buildings. The water is normally supplied at a pressure of 40 to 70 psi (pounds per square inch).

Typical Water Service Piping from Public Water Main to Building Interior

The 1/2 inch or 3/4 inch diameter service piping carries the water from the street mains to the house. Some early service pipes were 3/8 inch diameter. Most or all of this cannot be seen.

Lead Water Service Piping

Lead piping was used between the street main and the house up until the 1950s.

A good deal of lead supply line is still in use, and the health authorities indicate that as long as it is used regularly, there is no difficulty with it. If the water has not been run for some time, many recommend that the water be flowed for several minutes before using it. The life expectancy of lead piping is indefinite.

See details at LEAD PIPES in BUILDINGS

Other water piping materials: Copper, Galvanized Steel, Plastic

Copper piping has been used extensively since the early 1950s for supply lines from the city main to the house. From 1950 to 1970, 1/2-inch diameter piping was used commonly. After 1970, 3/4-inch diameter copper service piping has been common.

The life expectancy of copper piping is dependent on water conditions. In many areas, its life expectancy is indefinite. In harsh water or soil conditions, it may fail within 20 years.

• Details are at COPPER PIPING in BUILDINGS

Galvanized steel is not commonly used as a service pipe, although galvanized steel fittings may be found at the point of entry into the house. Where galvanized service piping is used, it is typically at least 1 1/4-inch diameter. The word galvanized means zinc-coated. The coating helps prevent the steel from rusting.

• Details are at GALVANIZED STEEL WATER PIPING

Plastic water service piping may be polybutylene (PB), polyethylene (PE), cross-linked polyethylene (PEX), polyvinyl chloride (PVC) or chlorinated polyvinyl chloride (CPVC).

Most plastic piping is buried at least 18 inches deep. Exposed piping may be subject to mechanical damage and deterioration from sunlight.

• Details are at PLASTIC PIPING ABS CPVC PB PEX PPR PVC

Common Water Service Piping Defects and Problems

Leaks in Water Service Piping

Since the supply line from the street cannot be seen, no comment is offered during a home inspection. If there is a leak, it may go undetected for some time. In some cases, water can be heard running outside the basement wall. Water accumulating in the basement or a wet spot on the lawn is often the first indication.

Leaks may be caused by building settlement, excavation, poor connections, faulty valves or a flaw in the pipe itself.

The underground water service line from the property line to the house is owned by the homeowner. Beyond the property line, the pipe is the responsibility of the city. A leak in the pipe requires excavation, and it is often difficult to know whether the leak is on the city’s or the homeowner’s side.

The city is usually contacted and they excavate their section of the pipe, correcting the problem if they discover it. If no problem is found, the homeowner is left to correct the problem on his or her own. In some cases, the homeowner must pay for the city’s work if the city pipe is not at fault. Some municipalities use sophisticated leak detection equipment.

Low Water Pressure Due to Clogged Service Piping

Poor water pressure in the house may be the result of a partially closed or obstructed valve in the street. It may also be because of blockage, such as a stone or other foreign body in the pipe. New piping may be crimped during installation or become pinched under a rock during back-filling operations. This can also cause low water pressure.

City water mains may be undersized or deteriorated in older neighborhoods. Some cities have poor pumping and/or distribution systems. In these cases, low water pressure problems are usually experienced at every home in the neighborhood. The solution is to petition the city to improve its system.

Water Service Piping Too Small in Diameter

In most new housing, the supply pipe from the street to the house is 3/4-inch diameter. In older houses, the piping was as small as 3/8-inch.

Modern life styles and additional plumbing fixtures usually require a larger line, capable of providing more pressure and volume. Replacing this pipe is an expensive and disruptive job. It is often deferred as long as possible.

Shared Public Supply Service Piping May Cause Poor Pressure or Flow

In some older semi-detached (attached) and row houses, a single supply line would run under a front lawn, and then split to feed two houses. This often yields unsatisfactory water pressure for both houses and is often replaced with two larger, separate lines.

Pressure Regulator Needed on Public Water Supply Piping

Where municipal water pressure is above 80 psi [perhaps even above 70 psi], a regulator is needed and should be provided to reduce the in-house pressure to prevent leaks at fixtures, stress on appliance hoses and possible broken pipe joints.

Details are at WATER PRESSURE REDUCER / REGULATOR

Freeze-Up Problems with Municipal Water Supply Piping

It is unusual, although not impossible, for the service pipe to be too close to the surface, and to freeze during very cold weather. Many service pipes extend above grade just before they enter the house.

See WINTERIZE A BUILDING

Lead Municipal Water Mains or Water Service Piping

Up until World War II, most of the service pipes in built-up areas were lead.

While these generally provide good service, they are small in diameter and may have to be replaced. Also, lead is relatively soft, and if building settlement occurs, there is a chance of leakage or crimping the pipe. Leaks can also occur at connections as a result of long-term deterioration.

Lead Water Service Piping Connected to Steel Pipe Nipple: Leak Risk

Many of the old lead service lines were connected to a galvanized nipple – a short piece of steel pipe that was often in contact with the soil.

This pipe rusts on the outside and inside, and may be close to the end of its life. It is often wise to replace this as a precautionary measure. Galvanized steel service pipes typically last roughly 40 years.

See details at LEAD PIPES in BUILDINGS

- Adapted from Carson Dunlop Associates Home Reference Book.

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Continue reading  at LEAK TYPES, WATER SUPPLY or DRAIN PIPES or select a topic from the closely related articles below, or see the complete ARTICLE INDEX.

Or see PLUMBING SYSTEM INSPECT DIAGNOSE REPAIR FAQs - questions & answers posted originally at this page.

Or see these

Recommended Articles

• ARTICLE INDEX to BUILDING FREEZE PROTECTION
  
• ARTICLE INDEX to DRAIN SEPTIC SEWER PIPES
  
• ARTICLE INDEX to GAS APPLIANCES, PIPING, CONTROLS
  
• ARTICLE INDEX to HEATING OIL, OIL BURNERS, OIL FIRED HEATERS, OIL TANKS
• ARTICLE INDEX to PLUMBING SYSTEMS
  
• ARTICLE INDEX to PLUMBING VALVES
  
• ARTICLE INDEX to SEPTIC DRAINFIELDS & DBOXES
  
• ARTICLE INDEX to SEPTIC SYSTEMS
  
• ARTICLE INDEX to SEPTIC TANKS
  
• ARTICLE INDEX to T&P RELIEF VALVES
  
• ARTICLE INDEX to TOILET INFORMATION
  
• ARTICLE INDEX to WATER HEATERS
  
• ARTICLE INDEX to WATER SUPPLY, PUMPS, TANKS, WELLS
  
• ARTICLE INDEX to WATER TESTING
  
• ARTICLE INDEX to WATER TREATMENT SYSTEMS
• PLUMBING DEFINITIONS

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