Blocked drain? What to try before you call a plumber

A slow drain is annoying. A fully blocked one can stop the whole house. Before you reach for the phone, there are a few safe things worth trying. There is also a clear point where you should stop and call a professional, and we will be honest about where that line is.

First, work out what is blocked

Is it one fixture, like a single basin or shower, or is it everything draining slowly at once? A single slow fixture usually means a local blockage in that trap or branch. If every drain in the house is sluggish, or the lowest one gurgles and backs up when you flush, the blockage is likely further down the main drain. That second case is one to leave to us.

Safe things you can try yourself

• Hot water. For a kitchen sink that is draining slowly with grease, a kettle of hot, not boiling, water can soften and shift a fatty build up. Boiling water can damage some pipes and fittings, so keep it just off the boil.
• A plunger. A good cup plunger over the plughole, with enough water in the basin to cover the rubber, can clear a surprising amount. Block the overflow with a wet cloth first so you get proper suction.
• Remove and clean the trap. Under a basin there is a U bend you can often unscrew by hand, with a bucket underneath. A lot of basin blockages are just hair and soap sitting right there.
• A drain snake from the hardware store. A hand snake can reach a blockage a plunger cannot, if you are comfortable using one.

What to avoid

Go easy on supermarket drain chemicals. They can clear a light blockage, but they are harsh, they do not touch tree roots or a collapsed pipe, and if they sit in a fully blocked drain they create a caustic mess that the plumber then has to deal with safely. If you have already poured chemicals in and it is still blocked, tell us when you call so we know what we are working with.

And please do not pour fat or cooking oil down the sink in the first place. It is the single most common cause of a slowly narrowing kitchen drain. We wrote a whole piece on how to avoid a fatsicle in your drain because we see it so often.

When to stop and call a plumber

Stop and call us if any of these are true:

• More than one fixture is blocked or backing up at the same time.
• Water or waste is coming back up out of a gully trap, shower or toilet.
• The blockage keeps coming back after you clear it, which often means roots or a damaged pipe.
• There is a smell of sewage, which can mean a blockage in the main drain.
• You have tried the safe steps above and it has not budged.

What we do that you cannot at home

This is where the right gear matters. We carry a drain machine, which uses a rotating cable to cut through solid blockages and tree roots, and a hydro jet, which uses high pressure water to scour grease and sludge off the inside of the pipe. We choose the tool that matches the blockage, and sometimes use both.

Just as important, we find out why it blocked. A repeat blockage is almost always a sign of something underneath, most often a tree root that has found a cracked clay pipe. One of our customers had exactly that, a root through a clay pipe causing a major blockage, and the lasting fix was to replace that section of pipe. As a licensed certifying drainlayer, Mark can do that work and sign it off. You can see the full picture on our drainage and drainlaying page.

The short version

Try hot water, a plunger, and cleaning the trap on a single slow fixture. Leave chemicals alone. If more than one drain is affected, if waste is backing up, or if it keeps returning, call 027 247 3030. We will clear it and tell you what caused it, so you are not paying to fix the same blockage twice. If you would rather just book it in, our contact page has all our numbers.