Sinks can easily become blocked, kitchen sinks often become blocked with food particles whereas bathroom basins often become blocked with human hair etc. Removing the blockage is normally quite easy and can often be done in a matter of minutes.

Chemical drain un blockers are not recommended as most of the plumbers I have spoken to often get called to houses where the sink is blocked and somebody has put a chemical un blocker down. Obviously if the chemical un blockers worked there would be no need for a plumber to be called out! These chemicals are also potentially harmful.

All sinks and toilets are connected to the foul water drain of the property, hence there is a trap between the drain and the toilet or sink. This trap is full of water all the time and has two purposes, firstly it creates a seal and prevents foul gasses from entering the home from the foul water drain, secondly if a piece of jewellery such as a ring is lost down the sink it will be caught by the trap and can be recovered easily. Traps vary in appearance and some are U shaped and others are simply a bottle shape. These traps often get clogged with debris from the sink, hair is a favourite in the bathroom and food particles in the kitchen! These blockages actually seem much worse than they actually are, and can easily be rectified with the correct tools. You will need a plunger to dislodge the offending obstruction, if you do not have a plunger you will have to unscrew the trap from below.

Unblocking a sink by removing the waste trap

1. firstly make sure that if the sink is full of water that you put the plug in the drain for the sink or you will get extremely wet.

2. Place a bucket or suitable container beneath the trap underneath the sink and remove the trap, some bottle traps simply twist off and U shaped traps have two retaining nuts.

3. empty the contents of the trap into the bucket, making sure that the pipes that attach to the trap are clear.

4. replace the trap and check for leaks, if one of the unions is leaking, wrap some PTFE tape around the thread.


sink waste trap

This kitchen sink waste trap can be removed by undoing the two plastic union nuts at each side

Unblocking a sink using a plunger


block overflow

Firstly temporarily block the overflow for the sink with some wet tissue or similar. This prevents the air which is going to be forced down the trap from escaping via the overflow!

sink plunger

Using a suitable plunger place the end completely over the waste for the sink, ensure there is water in the sink to create a seal.


Then Push down on the plunger several times with both hands, this will force water through the waste pipe and dislodge the blockage.

You may need to use one hand to prevent the tissue being forced out of the overflow, but this is one of the best methods for removing that blockage!

unblock sink

Another variation on the plunger is one of these blast unblockers.

To use one of these fill the sink or bath with a little water and ensure that the overflow is blocked as in the picture above. Place the end of the blast un blocker over the sink hole and pull up the handle, this will suck in some water. Now push the handle down fast and a jet of water will be forced through the waste pipe and this should remove any blockages. It may be necessary to do this a few times.