Blocked toilet or sink? What works, what makes it worse

Sinks and basins

1. Remove and clean the trap (the U-bend) with a bucket underneath. Most basin blockages are hair and soap right there.
2. A cup plunger with the overflow blocked by a wet cloth.
3. A drain snake or zip-strip for hair.

Avoid caustic soda and sulphuric acid drain cleaners. They damage old pipes, sit in the trap and burn whoever opens it next, which is often us.

Toilets

Use a flange plunger, not a cup plunger. A dozen firm pushes usually shifts it. If the water rises when you flush elsewhere too, the blockage is further along the drain.

Signs the drain itself is blocked

More than one fixture backs up, gurgling from other plugholes, or a smell outside near the manhole. That needs rods or a jetter and is a fixed-price job for us, usually the same day.