Restoration Guide: Water Supply Distribution

Editor's Note: This is article 12 of 16 in Chapter 8: The HVAC/Plumbing Guide of Old House Web's Home Restoration Guide. This guide was developed and edited for old homes from original materials in the U.S. Housing and Urban Development (HUD) Rehab guide.

12. WATER SUPPLY AND DISTRIBUTION SYSTEMS

Section 1--Overview

The water supply and distribution systems found in old houses are largely dependent on when the home was constructed. Your home's distribution system could be steel, copper, plastic, or a combination of all three.

This article takes a look at the water supply and distribution systems you may find in old houses, offers suggestions for improving the efficiency of existing distribution systems, and examines options for installing a new water supply system during a home restoration.

Section 2--Rehabbing and Replacing Old House Water Supply and Distribution Systems

Water supply and distribution systems have come a long way since the days when having indoor plumbing was a dream come true. Many homes with early water distribution systems used galvanized steel and iron piping with threaded fittings, and quite a few of those systems are still functioning today. Copper tubing was approved for use during the early 1930s and plumbers found it to be lighter and easier to work with. Most of the homes built between the late 1940s and the early 1970s used copper for water supply lines, and as long as joints were soldered properly and the piping was protected from freezing, the distribution system was very durable.

The 1970s brought advancements in material technology, and a desire to reduce the cost of home construction, and various plastics were introduced for water supply and distribution systems. Some plastic water piping has turned out to be an adequate replacement for copper; others such as polybutylene fittings did not turn out as well.

A home restoration is a good opportunity to address any problems with an existing water distribution system such as leaks, low water pressure, or missing pipe insulation. Some issues with a distribution system may not wait for a home restoration, the possibility of lead piping and its potential health hazards should be addressed as quickly as broken pipes or failed joints.

Working on existing water supply and distribution systems may entail bringing the system up to modern code standard, which isn't necessarily a bad thing. While it can cause you to spend a little more while remodeling, you may notice a huge improvement in water pressure and a decrease in the amount of usage each month. . Mechanical engineers and plumbing contractors now take many factors into consideration when designing a water distribution system and most plumbers in the past did not have the benefit of this knowledge.

Section 3--Make Your Water Distribution System More Efficient

The average home has increased in size over the past century, what was considered adequate square footage during the 1940s and 1950s is now considered small. Homes built during that time period often used a single pipe water distribution system, which could mean long waits for hot water. As homes increased in size, loop hot water distribution systems came into being and recirculated hot water throughout the home. Waits for hot water were reduced, but energy bills went up. There are now modifications which can be made to a loop system which can make it more energy efficient, and single pipe system modifications can reduce the wait for hot water. Manifold water distribution systems have also come into use and are reported to reduce water usage, and make a system more efficient.

3.1: Install New Copper Piping During Your Home Renovation

If the water distribution system is old and full of leaks, it may be worth your while to remove the existing system and replace it with a new copper pipe distribution system. The best time for a project like this is when you are doing a major home renovation and have access to the framing behind the sheetrock. Attempting to repair an old existing distribution system may be simply putting off the inevitable, and once your remodeling is finished it can be very expensive to change plumbing piping.

3.2: Install Chlorinated Polyvinyl Chloride (CPVC) Piping During Your Home Renovation

CPVC is an alternate choice to using copper piping for your water distribution system. CPVC has a lower cost than copper and is easier to work with. It has been used in homes since the 1950s, and doesn't require soldering. Care should be taken that installation isn't done in extremely hot weather as joints may later fail, and room should be allowed for pipe expansion as temperatures change.

3.3: Install Cross-Linked Polyethylene (PEX) Piping during Your Home Renovation

PEX is another alternative to using copper for your old house water distribution system. It is light and easy to work with and allows long runs without joints as it is available in coils. Some local plumbing codes have not yet approved its use, so check before plumbing your home with it.