The plumbing system in your home is simpler than you might think. Find straightforward information about pipes, fittings and the fundamentals of plumbing repair.
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The foundation of your plumbing system is good piping and strong joints. Pipes may be made from a variety of materials, including cast iron, ABS plastic, Pex piping, etc. The most common used materials for residential plumbing, however, are copper pipes for water-supply lines and PVC plastic for drain lines.
Though copper piping is relatively expensive, it's durable and comes in a variety of grades. Type M is the most basic grade and meets minimum building codes. It is thin-walled tubing and is marked for identification with red lettering. Type L is about twice as strong as type M and is a good choice for upgrading your plumbing system. It is marked with blue lettering. Type K is even stronger and is intended mainly for commercial use. It is marked with orange lettering. Soft copper tubing is sold in a coil and bends easily. It's well suited for use in tight spaces and in situations involving awkward bends, and it requires fewer joints.
A tubing cutter is the best tool for cutting copper pipe. Turn the handle to tighten the blade against the pipe as you twist the cutter around the pipe in a circular motion. Several turns are usually sufficient to cut through the pipe. Most cutters also include a reamer tool -- a short blade used to remove metal burrs after the pipe has been cut. A mini-cutter is handy for cutting pipe in tight spaces.
The term "potable" is important to know when purchasing any type of pipe. Potable means suitable for drinking. Be sure that any pipe purchased for indoor water use is approved for potable water or marked NSF61 by the National Sanitation Foundation.
There are three major types of pipe used in potable plumbing today; copper, CPVC and PEX. Each has its own pro's and con's. Before using any type of plumbing, check the local codes to see what type is approved for the area.
There are a number of different types of fittings that can be used to join two sections of all of these pipes, including a 90-degree turn, a 45-degree turn, a coupler and "T" fittings.
PEX stands for Cross-linked Polyethylene. It's a really strong, flexible pipe.
PEX comes in lengths like copper pipe and PVC, as well as long rolls.
With PEX, you can pull an entire pipe run and only have to make two joints. The pipe moves like wire or a hose and can be snaked into position.
The types of fittings are the same as other pipes, but they go inside the pipe instead of the outside. Because the pipe is flexible, you'll use fewer fittings.
When connecting to a soldered connection, PEX has special fittings to do the conversion.
Be careful when running PEX not to kink the pipe so the water flow is not disrupted.
All pipe joints start the same with cutting and measuring. Mark the place on the pipe to be cut, and then make the cut-keeping it square. Make sure there aren't any small pieces in the pipe, and then slide on a crimp ring. Use slip joint pliers to slide the ring into place, between 1/8 inch and 1/4 inch from the end of the pipe. Put the crimping tool over the ring, and then squeeze. The joint should be in place. Test the line with water or air before closing up the area.
PVC Pipe, Fittings and Joints
Polyvinyl chloride (PVC) piping has revolutionized modern plumbing. Before PVC was available, most drain lines were made of cast iron and connected at joints with molten lead. Like copper, PVC pipe comes in different grades or "schedules." Schedule 40 is sufficient for most home plumbing, although the heavier schedule 80 is an option for more substantial jobs.
Cut PVC using a short, thick-bladed PVC saw. Line up the saw square with the pipe and, using short strokes, make a groove at your mark. Now apply pressure and use longer strokes. After making the cut, use the tip of the saw to ream out burrs. Always wear safety glasses when cutting PVC.
Other options for cutting PVC include a power miter saw or a PVC cable saw. A power miter saw is a great time saver and makes cleaner cuts. A masonry blade is recommended when cutting PVC with power saws. Always take proper safety precautions when working with power tools.
When using a cable saw, begin by looping the saw around the pipe and holding both handles firmly. Quickly move the cable back and forth, beginning with short strokes. As you lengthen the strokes, the rapid motion creates heat, and the cable melts its way through the pipe. Break the pipe off quickly before the plastic cools and hardens.