Blocked Sink or Floor Trap in Singapore: 5 Things to Try Before You Call a Plumber

A slow drain is one of the most common calls we get in Singapore, usually in an HDB kitchen or bathroom where grease, hair and soap build up quietly over months. Most of the time you can clear it yourself in ten minutes with things already in the house. Here is the order to try them, and how to tell when it is time to stop and call someone.

What you will need

• Rubber gloves and a bucket
• A flat-cup plunger, not the toilet bowl one, for sinks and floor traps
• A wet cloth to seal the overflow hole
• Baking soda and white vinegar
• A torch, so you can actually see inside the trap

1. Clear what you can see

Lift the sink strainer or the floor trap cover and pull out hair, food scraps and built-up soap scum by hand. In most bathrooms the blockage is sitting just under that cover, and this alone fixes more blockages than people expect.

2. Plunge it properly

Block the overflow hole with a wet cloth so the pressure has nowhere else to go. Add enough water to cover the plunger cup, then push down firmly and pull up about ten times without breaking the seal. A flat-cup plunger seats better on a flat sink or floor drain than the rounded toilet type.

3. Flush with hot tap water

Run hot water from the tap for a minute or two to soften grease sitting in the pipe. Do not pour boiling water straight down the drain. It can crack or warp some pipes and fittings, particularly older PVC traps.

4. Try baking soda and vinegar

Pour half a cup of baking soda into the drain, follow with half a cup of white vinegar, and leave it for fifteen minutes before flushing with hot tap water. This helps with light grease and smells. It will not shift a solid blockage, so do not repeat it more than once expecting a different result.

5. Clean the trap under the sink

Place a bucket under the U-shaped trap, unscrew the two connectors by hand, tip out the contents and refit it. Tighten it snug, not forced. If it will not come loose easily, or it leaks after you refit it, stop there and call a plumber rather than risk cracking the fitting.

Why sinks and floor traps block in the first place

• Kitchen sink: grease and food scraps that harden inside the pipe over weeks
• Bathroom basin and shower: hair and soap scum building up at the trap
• Floor trap: hair, lint and detergent residue, often from a nearby washing machine outlet
• Occasionally: a blockage further down a shared pipe, which no amount of plunging at your end will clear

Signs you need a plumber, not another home remedy

• More than one drain in the flat is slow or blocked at the same time
• The drain gurgles or smells even after you have cleaned it
• Water rises up through the floor trap when the washing machine drains
• The blockage comes back within a few days of clearing it
• You have tried the steps above and water still will not drain properly

Go easy on strong chemical drain cleaners. They can damage older pipes over repeated use, and they are unpleasant on skin and eyes if they splash back while you are working. Never mix different cleaning products together in a drain.

Keeping it from happening again

• Wipe greasy pans with paper before washing up
• Use a fine sink strainer and empty it daily rather than weekly
• Clear the floor trap cover of hair every week, not just when it smells
• Rinse the kitchen drain with hot tap water after washing up, especially after cooking with oil

Need it fixed today?

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