Pipes, tubes, lagging and fittings

Pipes, tubes, couplings, lagging, vents, valves and joints may be familiar terms, but what do each of them do and how do they affect your plumbing systems? These are the things behind the scenes that keep your plumbing system together - they are the glue, if you like, that prevents your plumbing system from falling apart, and the bits and pieces that ensure water and gas go where they're supposed to, when they're supposed to.

Understanding what these parts are will give you a better idea of how your plumbing works, and in turn what's likely to affect how well it does its job.