Identifying the leak under the sink

So you’ve sprung a leak, noticed by warping boards or mysterious pools and puddles gathering at your feet as you do the dishes. Let’s take a look at where the leak is coming from.

1. Drain pipe Leaks

Problem: Drain leaks occur in the pipes that drain the water from the sink. The leak may be due to a cracked seal around the strainer, a blockage in the p-trap pipe or corrosion of old metal pipes.

Solution: Tighten the compression nuts on the p-trap. If this doesn’t stop the leak, remove it and clean it. It’s also a good idea to clear the drain line in case of any blockages.

If you struggle to turn the nuts on an old metal pipe, this is a sign of corrosion, and the p-trap will need to be replaced. (Read: 6 ways to unblock a drain)

2. Water Supply Leaks

Problem: Water supply leaks are from the pipes under the sink leading to your faucet. This water is usually pressurised and leaks are noticeable by a sudden spray or steady drip or dribble.

Solution: Usually the compression fittings need to be tightened. The easiest way to do this is to hold the valve with one wrench and tighten the compression nut with the other.

3. Faucet Leaks

Problem: Faucets usually leak around the base of the tap, but the leak may dribble down underneath the sink.

Solution: The cure depends on the type of tap – split mixer or single tap. Usually a washer or gasket needs changing, but if it is old, the whole faucet may need replacing.