Since we were talking last week about fixing frozen pipes, I thought that it would be good to cover the household plumbing system in general (probably should have covered that first). When it comes to their water some people have only the vaguest notion of where it comes from before it spatters out of the end of the pipe. This part of your household water system I would term the supply or distribution side (as opposed to the drain side). Its job is to take the water from where it comes into your home and get it (without too much loss) to where it is used.
Water usually comes into your home, from your city water supply or well, in the basement, or maybe in the utility room if you live in a ranch. We’ll start with this end and work our way to the other. The first item that you will encounter is your main shut-off valve. This can be very important, as it will shut off all the water in the house. Knowing how (and where) to turn off the water can be very handy some disastrous day.
After the main shutoff the pipes start to travel and branch off to the various places in the home where water is used. Somewhere along this line some of the water will branch off to the water heater, a tank-like affair (of course there are now new tank-less models) where gas or electricity is used to heat the water automatically. After the water heater, the hot water lines, like the cold, wander off through the house to your bathroom, kitchen and utility spaces. There are often branch shut-off valves (or at least there should be) in these lines like the main, that can be used to isolate smaller sections of your water system leaving you with at least some water in case you have to shut an area down.
When these lines get to where the fixtures that use water are located they usually come out of the wall or floor, and have yet another valve. This one is usually small and chrome, and is called a supply stop. You have probably seen them under the sink or toilet. These just shut off the single fixture and serve as the final link in you home’s plumbing. From these valves soft copper or plastic tubing or often these days, hoses run the final few inches to the fixture.
These plumbing lines can be made of several materials depending on the age of your home. Older homes often have galvanized iron pipe and fittings. These are still available, but are not often used as they are difficult to install and will eventually rust out. They can also rust in, where the pipe will not spring a leak, but the pipe will rust shut on the inside, leaving you with only a trickle of water passing though. Replacement is, alas, the only option.
Mid-aged homes usually have soldered copper plumbing. Sturdy and leak resistant, copper will last many years in most applications. Copper can be more difficult to repair, though, as repairs must be cut out and new sections soldered in. Special compression and push fittings are now available that can make copper repair easier.
Plastic tubing, both white PVC (cold water only), and beige CPVC (hot or cold) are common in newer homes. They are solvent welded (glued) together and are easy for the novice to work with. The two types are not interchangeable, however and the correct matching tubing and fittings must be used for each type.
The newest type of pluming systems, now being run into more often in new homes is Pex tubing. Pex is special tough plastic that is semi-flexible and can be snaked through the walls without elbows to make the bends. This makes it fast and easy to put in and that is why you will run into it more and more often. Pex uses either barb type fittings with crush ring type clamps (easy to install with the right tools, impossible without), or push type no-clamp fittings that while more expensive, are easy for the layman to use.
That about covers the types of plumbing that you are liable to run into when making home repairs. All can be successfully dealt with by the average handyman, and even if you choose to call in a professional, it is good to know what you are dealing with when the time comes.