Blocked toilet or sink: what works and what damages
By FixNow24
Recognising where a blockage sits, the gentle methods that really work, the products to avoid, and the signs that point to a shared stack in the building.
Finding where the blockage sits
A single fixture backing up almost always means a local blockage, in the trap or just after it. If several fixtures drain badly at the same time, or if water rises in the shower when you flush, the problem sits further along, on the shared waste.
In a block of flats, ask the neighbours on your floor and on the floor below whether they see the same thing. A blocked stack is the building’s responsibility, and the detailed invoice from the professional is what lets you claim it.
The gentle methods, in the right order
For a sink, take the trap apart after placing a bucket underneath: in most cases the blockage is right there, made of grease and hair. Rinsing it and refitting the seals carefully is often enough to restore the flow.
A plunger still works well if you block the overflow with a damp cloth, so that the pressure really goes towards the pipe. Work with steady movements rather than violent jerks, which move the water without acting on the blockage.
Boiling water does not suit ceramic toilet pans or older plastic pipes, which it can distort. Very hot but not boiling water, poured slowly into a sink, gives better results without any risk.
What to avoid, and when to call
Chemical drain cleaners attack seals and older pipes, and remain useless against a blockage made of wipes or grease. If they have not worked, they sit in the pipe and make the job unpleasant: always tell the professional you have used them.
Call a professional if water rises in another fixture, if the smell becomes strong, or if the blockage returns a few days after being cleared. That return often points to a cause further upstream that a camera inspection can identify.
On FixNow24 you pay a €35.00 call-out fee when you send the request, and the indicative range for the job runs from €8.48 to €1,908.00 incl. VAT at the 6 % rate, and from €9.68 to €2,178.00 incl. VAT at the 21 % rate. While you wait, stop using the fixture concerned and clear access to the trap or the inspection chamber.
To stop the problem coming back, change two or three simple habits. Never put wipes, cotton pads or cat litter down the toilet, even when the packaging calls them biodegradable: they do not break down fast enough in a building’s pipework. Pour cooled cooking fat into a container rather than down the sink, where it sets and holds everything else back. Fit a hair trap in the shower and clean it weekly. Finally, run water regularly through fixtures you rarely use: a dry trap lets smells come back up.