Drainage is one of those services that no one appreciates until it stops working. Before you call a plumber, here are some simple methods you can try yourself to clear blocked drains.
You should be aware of what goes into your drains in the first place. Try to avoid tipping cooking grease down the sink; and use a drain protector to trap large items. This is especially important in kitchen sinks, which often attract large pieces of food, and baths, which can become clogged with hair. You should also make a habit of clearing out any hairs or pieces of garbage that become stuck around the plughole.
You can also keep your drains healthy by regularly (and carefully!) pouring hot or even boiling water down them. This can help unclog small blockages which have not yet become large enough to be a problem.
If your drains do become blocked, the rule is to start with the mildest chemicals and work your way up. Begin by pouring down boiling water as described above, always taking care to avoid being splashed. If this does not work, you can make your own drain unblocker by pouring down half a cup of baking soda, followed by a mixture of one cup of vinegar and one cup of hot water. Leave the drains for five to ten minutes, then flush with boiling water. The reaction between the vinegar and soda should unclog most blockages.
If your drain remains blocked, you can try using a commercial drain cleaner made with caustic soda. Make sure you use rubber gloves when using the product, and ensure you follow the manufacturer's instructions, as these chemicals can be hazardous.
If none of the above work, you can try to remove the blockage by using a drain auger or snake. These are easily available from hardware stores and consist of a coiled spiral snake that pushes into the drain to physically clear the blockage. If you do not have one at home, you can always improvise with curtain wire; beware of using anything too stiff, like a coat hanger, which could damage your pipes.
If none of these methods work, never fear; you always have the option of calling in the professionals. A plumber will have the tools and experience to clear the problem and will be able to offer advice to stop it from happening again.