Blocked drains can be a major nuisance. In addition to preventing homeowners from using their sinks, showers or toilets, blocked drains can also cause major damage, if they lead to a water pipe bursting open. Here is a quick explanation of this problem.

What causes a drain to become blocked?

In most cases, blocked drains are caused by things such as oils (particularly those that solidify at room temperature), food particles, coffee grounds, hair and soap scum being allowed to enter a plumbing system.

Many homeowners don't bother putting drain strainers in their sinks or hair catchers in their showers and bathtubs. As a result, the aforementioned substances get into the water pipes and gradually, over a period of several weeks or months, form clumps which create a blockage.

What are the signs that a drain is blocked?

One of the most obvious signs of a blockage is the water in a sink either draining very slowly or not draining at all. However, there are a number of other things that can also indicate that a drain has become blocked. An unpleasant odour is one example; this usually happens when the food particles that have formed a blockage in a pipe begin to rot. Gurgling sounds emerging from the drain are yet another sign that there may be a blockage somewhere inside the plumbing system.

What can be done about this problem?

There are several ways to handle a blockage. A plunger is usually the first tool which should be used in this situation. The pressure and suction created by the plunger can often be enough to dislodge a minor blockage.

Another manual tool which can be effective is a drain snake; this is a long piece of pliable wire which can be guided into a drain and twisted; this motion enables it to grasp and break up the clump inside a pipe. Because this tool is very long, it's particularly useful for blockages which are located deep within the plumbing system.

Chemical unblocking agents are another option; however, these are extremely abrasive and can therefore sometimes end up corroding the pipes that they are poured into. As such, they are generally only recommended for severe blockages.

If none of the above-mentioned methods work, then a plumber will need to be called to address the issue. They may use their own specialist tools to unblock the drain or they might disassemble some of the piping, in order to manually remove the blockage.