Plumbing or drainage — what is the difference?

The distinction sounds academic until you are on the phone trying to describe a problem — and it decides who you should be calling.

Plumbing

The pipework bringing clean water into the property and distributing it: supply pipes, taps, showers, the boiler, radiators, cylinders and the connections to appliances. A plumbing fault usually shows as a leak, low pressure or no hot water.

Drainage

Everything taking waste water away: waste pipes, soil stacks, gullies, underground drains and the connection to the sewer. A drainage fault usually shows as slow draining, a blockage, a smell or water backing up.

The quick test

Is water arriving where it should not be, or not arriving where it should? That is plumbing. Is water failing to leave? That is drainage.

Who is responsible

Inside the property boundary, generally you. Beyond it, usually the water company — including many shared drains that were transferred to water companies in 2011. Before paying for major work on an underground drain, it is worth establishing which side of that line it falls on.

Overlap

Plenty of jobs are both. A leaking toilet is plumbing at the cistern and drainage at the pan connection. Any competent plumbing and heating firm handles both, which saves you working out the answer yourself.