The most common source of drain blockage inside a home is an accumulation of the soaps and shampoos that we are use so frequently. Most of these products have a base of animal fat. When they are rinsed down the drain, they tend to cool and cling to the inside of your drain lines where they act like “glue,” causing other debris (hair, rust, mineral sediment in the water, toothpaste, coffee grounds, food particles, etc.) to attach themselves to the walls.
The most vulnerable locations for this process to happen are the parts of the drain system furthest from the drain itself, or any places where the line is fairly horizontal and the speed of the running drain water slows down.
A drain line from a sink or tub usually consists of pipe with an inside diameter of 1-1/2 inches, part of the system designed to carry away your waste water. However, as a clog slowly develops in the line, the diameter of the pipe is narrowed, slowing the water flow in it. This reduced flow then allows even more debris to cling to the sides of the drain line, exaggerating the problem further. Soon you can have an opening the size of a straw, which will eventually close totally.
When faced with a difficult stoppage many do-it-yourselfers will wonder how to snake a drain. The answer to this common question depends on which type of drain you are going to snake. If you are looking up how to snake a drain then most likely plunging did not work. Plunging a drain is usually the first thing to try because it is the quickest and easiest way to clear a stoppage. When a plunger is not enough to clear a clog the next step is to use a drain snake. A quick word about drain snakes is necessary before I outline the instructions for how to snake a drain.