Many minor blockages can be cleared without calling anyone. The trick is knowing which ones, and stopping before a simple problem becomes a messy or expensive one.
This guide covers what you can reasonably try at home, what to avoid, and the signs that the blockage is somewhere you cannot safely reach.
First, work out where the blockage is
Before you do anything, check which fittings are affected.
- One fitting only (for example, just the kitchen sink): the blockage is probably in that fitting’s trap or waste pipe. This is often something you can deal with.
- Several fittings at once, or water rising in the toilet when you run a tap: the blockage is likely to be in the underground drain. That usually needs proper drain rods or jetting.
- Water rising in an outside gully or inspection chamber: the underground drain is blocked somewhere downstream of that point.
Blocked sinks and basins
- Stop running water into the sink.
- Use a sink plunger. Cover the overflow hole with a damp cloth so the pressure goes down the pipe rather than out of the overflow, then plunge firmly a dozen times.
- Clean the trap. Put a bowl underneath, unscrew the plastic trap under the sink by hand and clear out any grease, food or hair. Refit it carefully so it does not leak.
- Clear the plughole. In bathroom basins, hair often collects just below the plug. A cheap plastic hair-removal strip can pull it out.
If the trap is clear and the sink still will not drain, the blockage is further along the waste pipe or in the gully outside. See our page on blocked sinks for what usually causes this.
Blocked toilets
- Stop flushing. Each flush adds more water and risks an overflow.
- Use a toilet plunger: the type with a flange that fits into the outlet. Push gently at first to expel air, then plunge firmly several times.
- Wait and try again. Sometimes paper softens and clears after half an hour.
If the water level rises when you use other fittings, or plunging makes no difference, the problem is probably beyond the toilet. Our guide on why a toilet keeps backing up explains why.
Outside drains and gullies
A gully that is blocked with leaves at the grid can often be cleared by hand. Wear thick rubber gloves, remove the grid and scoop out the debris.
If water is standing in an inspection chamber, the blockage is in the underground pipe. Drain rods can clear some blockages, but there are real risks:
- Heavy iron manhole covers can cause back injuries and crushed fingers.
- Rods can come unscrewed if turned anticlockwise, leaving a section stuck in the drain.
- Pushing hard at a blockage can compact it or damage an older clay pipe.
- Sewage carries bacteria, so always wear gloves and wash thoroughly afterwards.
If you are not comfortable with any of that, it is a job for a drain unblocking company.
What to avoid
- Chemical drain cleaners on a full blockage. They rarely clear it, can damage some pipes and leave caustic water that is dangerous to anyone who later has to work on the drain.
- Boiling water down plastic pipes. It can soften joints. Hot tap water is fine.
- Wire coat hangers in toilets, as they scratch the pan and rarely reach the blockage.
- Pressure washers pushed into drains. Domestic machines are not designed for this and can force water back out of the pipe.
When to stop and call someone
Call a professional if:
- Water or sewage is rising in more than one fitting or outside.
- The blockage comes back within weeks.
- You can smell sewage and cannot find the cause.
- A plunger and trap clean have not worked.
- You would need to lift a heavy cover or rod an underground drain and are not confident doing so.
If you are in or around Southampton, we can help. See drain unblocking in Southampton or get in touch.