How to Fix a Slow Draining Sink? Quick NZ Guide

A slow draining sink might seem like a small inconvenience, but it’s usually a sign of a growing blockage in your plumbing. Left unattended, that sluggish drain can turn into a full clog, bad odours, or even water damage under your sink.

At Water Works, our licensed plumbers see this problem every day, and the good news is, it’s usually easy to fix when caught early. Here’s a simple guide on how to fix a slow draining sink and when to call a professional for help.

Why Is Your Sink Draining Slowly?

A slow draining sink can happen for several reasons, including:

• Built-up grease and soap scum inside the pipes
• Food particles and coffee grounds trapped in the drain
• Hair and debris stuck in the plughole (common in bathroom sinks)
• Blocked P-trap under the sink
• Issues with your main drainage line

Identifying the cause early can prevent more costly repairs later.

How to Unblock a Slow Draining Sink

If your sink is draining slowly, try these simple steps to unblock a slow draining sink safely before calling a plumber:

1. Boiling Water Flush

Start with the simplest method by pouring boiling water down the drain in two or three rounds. This can help dissolve grease or soap build-up inside the pipes.

2. Use a Plunger

Place a cup plunger over the drain and create a tight seal. Pump up and down several times, then quickly pull up to release. This creates suction that can dislodge minor blockages.

3. Clean the P-Trap

If plunging doesn’t help, place a bucket under the P-trap (the curved pipe below your sink), unscrew it carefully, and clear out any trapped debris. Reinstall the trap and test the drain again.

4. Try Baking Soda and Vinegar

Pour half a cup of baking soda followed by half a cup of vinegar into the drain. Wait 10-15 minutes, then rinse with hot water. This natural reaction can help break down organic residue.

5. Avoid Chemical Drain Cleaners

While tempting, chemical drain cleaners can corrode pipes over time, especially older ones. If simple methods don’t work, it’s time to call a professional plumber.

When to Call a Professional Plumber

If the above steps don’t solve the problem, or if multiple drains in your home are draining slowly, the issue could be deeper in your plumbing or main sewer line.

You should call a licensed plumber if:

• Water backs up after using multiple fixtures
• You notice gurgling sounds or foul smells
• The slow drainage returns quickly after cleaning
• You’re not confident removing parts of your drain

At Water Works, our team uses advanced drain-clearing tools like hydro-jets and cameras to locate and remove blockages fast without damaging your pipes.

Preventing a Slow Draining Sink

Keep your sink flowing freely with these easy habits:

• Avoid pouring fats, oils, or grease down the drain.
• Use sink strainers to catch food scraps or hair.
• Run hot water for a few seconds after using your sink.
• Schedule professional drain maintenance every 6-12 months.

Get Expert Help from Water Works

If you’ve tried everything and your slow draining sink still won’t clear, don’t risk further damage. Let the experts handle it.

At Water Works, we provide fast, reliable drain-unblocking and plumbing services throughout Auckland and beyond. Our team will identify the cause, fix the issue, and help prevent it from happening again.

Call us today or book online & Save $15. Our emergency plumbers are available 24/7 across Auckland for fast, reliable help.