Most older homes are equipped with galvanized iron pipes for the hot and cold water and cast iron for the outgoing drain system. These materials have evolved to today's standards of copper piping for the incoming water and PVC plastic piping for the outgoing drainage. Gaskets and washers, which seal the faucets and drains, wear out and drip with the passage of time. Routine replacement is part of proper maintenance.

As the older, galvanized iron piping ages, the interior of the pipes rust and the pressure and volume drop. When this happens, the piping is often replaced either in part or totally with copper piping. (Some plastic supply piping is used but has not, at this time, gained great favor with the majority of plumbers).

A plumbing systems capacity can be examined by administering a functional flow test. This entails observing the flow and capacity of the water with the bathtub and sink fixtures flowing and the toilet tank filling. This is a more practical observation than a pressure test in that it reveals actual performance.

With the widened use of copper piping, the use of lead based solders have produced some potential for lead poisoning. Lead solders have now been banned for use on domestic water supplies.

If there is some concern, the water can be tested by a laboratory. Normal precautions to prevent lead poisoning include letting the water run free for a short period of time to flush the pipes.

Typically, any lead in the solder will leach out after a period of three years. At that time the water is generally considered safe for normal consumption.