After inspecting all the fixtures, associated pipes, and fittings in the interior rooms, the rest of the plumbing inspection is carried out in the basement. Some homes are built on ground level and do not have a basement. In those cases, this portion of the inspection will be performed as part of the interior room inspection.
Look for the entry of the water-supply pipe. It will be located near the foundation wall and will usually have a meter near the inlet. If you cannot find the water-service entry, ask the homeowner. Sometimes it is concealed behind boxes or storage shelves. The inlet service pipe will generally be made of copper, brass, or galvanized iron. However, in some older homes, you might find that the pipe is made of lead. A lead pipe can be detected by the type of joint between the sections. Lead pipes have wiped lead joints that appear in a horizontal section as a spherical bulge. (See FIG. 13-8.) There is usually a joint near the foundation wall. If you do not see a joint, you can gently scratch the surface of the pipe. If the pipe is made of lead, the surface will be relatively soft, and the scratch will expose an area with a silver-gray color.
Although a lead water pipe might be acceptable in a plumbing sense, it can be a potential health hazard. Depending on the quality of the water, some of the lead might dissolve out. Since the amount of lead that a person can safely absorb is limited and cumulative, by drinking this water over an extended period of time, the maximum tolerance level can be reached. If you find a lead inlet pipe, you should have the water analyzed for lead content. In many communities, the local health department will do the analysis free or for a very nominal charge. If the lead content is high, the pipe should be replaced. Again, remember that replacing the inlet pipe is not the responsibility of the water company; the cost must be borne by the homeowner.
During my inspections, I periodically find a lead inlet pipe. When I do, I always recommend to the prospective home buyer that as a precautionary measure the water should be analyzed. In one home, located in White Plains, New York, an analysis of the water revealed that it had seven times the allowable concentration of lead. Needless to say, that pipe was replaced.
If the water flow from the plumbing fixtures is low and the piping in the house is good (all copper or brass pipes and fittings with no leaks), the problem will be a constriction in the inlet water supply or low pressure at the street main. On several occasions, I have inspected houses where the old water pipes were completely replaced with new copper pipes and still the water flow was low. Further inspection revealed that even though the house had been repiped, the old galvanized inlet pipe had not been replaced. Under normal soil and water conditions, this pipe should last about forty years. As these pipes age, rust deposits build up on the inside, restricting the flow. Also, a galvanized iron pipe will eventually corrode from the outside and leak. Replacement can cost anywhere from several hundred to several thousand dollars, depending on the length of the line and ground conditions.
When domestic water is supplied by a utility company, the inlet pipe will lead directly to the house distribution piping. In some areas, depending on the quality of the water, there might be a water softener or a filter between the supply and distribution piping. Normally, however, you will not find a storage tank (similar to that needed in a well-pumping system) between the supply and distribution piping. If you do find such a tank, you should suspect a low-pressure condition at the street main. When the water pressure in the street main is low and there are simultaneous demands for water by the houses on the street, the flow to each house may be inadequate. To compensate for this condition, a storage tank is often installed to provide a reservoir to supply water during these periods. Water drawn from the tank is then replaced when the plumbing fixtures in that house are not being used. If you see such a tank between the inlet supply and distribution piping, record the fact on your worksheet.
When domestic water is not supplied by a utility company, it will be supplied by a well-pumping system. Such systems are discussed in the last section of this chapter.
At the house inlet side of the water-supply pipe, there will be a master shutoff valve that can close the water supply to the entire house. Sometimes there are two valves, one on each side of the water meter. See whether the valve is operational. Close and open it. Over the years, because of lack of use, the valve often freezes in the open position.