This section covers the main plumbing drain lines under the floor and in the walls. The information below is some general information and tips on drain repair. For the drains under the bathroom and kitchen sinks refer to the links above under the plumbing tab.
One of the most important steps in drain repair is when you are reinstalling the pipes and gluing them together. You must ensure that when you are applying the glue to the pipes that the pipe is dry, water will distort the glue and cause a leak.
Plumbing drains are ultimately controled by gravity. It is important that the drains have a slight fall towards the sewer or septic tank. The fall should be one 1/8 of an inch of fall per foot of pipe. So if the piece of pipe you are installing is eight feet long, there should be one inch of fall from one end of the pipe to the other end.
In older houses cast iron pipe or galvanized pipes were used for the drain, and galvanized pipe was used for the water supply lines. Inside the cast iron pipes after 30+ years a layer of debris builds up over time on the inside of the pipe. The best way to repair cast iron pipes is to cut it out back to the main drain and replace it with schedule 40 pvc.
The easiest way to connect cast iron pipes and pvc pipes is to use a rubber coupling
.
Tools Required
The tools required for repairing plumbing drains is a sawzall (or hacksaw) to cut the pipe,pvc glue, and cleaner.
Gluing Pvc Pipes
Step 1.
Wipe any water or dirt off the pipe and the fitting.
Step 2.
Apply pipe cleaner onto the pipe and fitting(Apply thoroughly). Pipe cleaner mixed with the glue creates a chemical reaction bonding the pipe and the fitting together.
Step 3.
Apply a generous amount of glue onto the pipe and the fitting.
Step 4.
Insert the pipe into the fitting, once inserted into the fitting twist the pipe a quarter of a turn holding the pipe and the fitting together tightly for 20-30 second's.
Upgrading your plumbing system to schedule 40 pvc for the drain and either copper or cpcv for the water lines will provide you with atleast 20-30 years of hassle free use for your plumbing system.
The easiest way to cut cast iron and galvanized pipes out is with a sawzall. You will want to use a demolition sawzall blade in the sawzall for cutting the cast iron and galvanized pipes and a metal sawzall blade to cut the pvc pipe. I recommend using two sawzall blades, one for the cast iron and galvanized pipes and one for the plastic. After cutting the cast iron or galvanized pipes with one sawzall blade it would be to dull and will make it harder to get good cut's on the plastic pipes using the same blade.
Make sure when you are cutting the pvc pipes to get a good straight cut on the end of the pipe. Too much of an angle on the end of the pipe might cause a leak. After cutting the cast iron or galvanized pipe out to replace them with plastic pvc pipes you would install a rubber coupling to adapt from cast iron to plastic to tie the new plastic pipe into the cast iron or galvanized main drain.
In some places where there are two plumbing fittings connected together with very little space between the two fittings, but you need to replace one of them. And if you cut the fitting out there is not enough pipe to glue the new fitting(or coupling)onto. If you cant cut out both fittings and replace new from there, you can cut the pipe between the fittings and use a plumbing socket saver to ream the existing pipe out of the fitting.
One of the most valuable tools in my plumbing repair tool box(actully i use a bucket) for drain repair is a socket saver. They are inexpensive and easy to use, but you can only get them at plumbing supply warehouses or dealers and you can only use socket savers on pvc pipe.
To use a socket saver, cut the pipe flush with the end of the fitting that is going to be reamed out. Then the socket saver will ream the old pipe out of the fitting so that a new pipe can be inserted into the fitting. Saving you time and money.
