| Plastic pipe and fittings can now be used for hot | | | | plastic is a poor conductor of heat compared to |
| water supplies and central heating. They are easy to | | | | metal (which means that, unlike metal, it provides a |
| work with and allow the DIY plumber to tackle a | | | | certain amount of insulation), and because it has |
| wide range of jobs. | | | | greater elasticity. This means that plastic pipes are |
| Over the last twenty years plastic has become the | | | | not only less likely to freeze than metal ones, but |
| most popular plumbing material for above and below | | | | also that in the event of their doing so they are |
| ground drainage, for rainwater collection and disposal, | | | | much less likely to burst. The greater degree of |
| and for subsoil drainage. In the form of black | | | | insulation that plastic provides also brings other |
| polythene tubing it has also become a material widely | | | | benefits: it results in less heat being lost from pipe |
| used for water transportation on camping sites and | | | | runs between radiators (or between the hot water |
| farms. In the home, however, if has not proved | | | | cylinder and the hot taps), as well as meaning that |
| popular. Although this lack of interest can partly be | | | | less insulation is necessary for pipework that needs |
| attributed to the conservatism of plumbers and | | | | to be protected against the cold. |
| householders, the main reason has been that up until | | | | Plastic pipes aren't subject to corrosion for the simple |
| now the plastic pipes that have been available have | | | | reason that plastic isn't attacked by the water supply. |
| been suitable for cold water supplies only. This has | | | | Electrolytic corrosion, which results in the build up of |
| meant that plumbers, who have had no choice but to | | | | hydrogen gas and black iron oxide sludge (magnetite) |
| use copper or some other metal for the hot water | | | | and can ultimately lead to leaky radiators and early |
| or central heating system, have almost always | | | | pump failure, is therefore far less of a problem when |
| tended to use the same material when dealing with | | | | a central heating system is fitted with plastic pipes. |
| the cold water system. Householders have doubted | | | | This also means that plastic is a safer material to use |
| the ability of plastic pipework to do a good, life-long | | | | for your drinking water supply pipes than metal, the |
| job, and have also tended to resist its use on | | | | use of which can, under some circumstances, present |
| grounds of taste. Quite simply, in places where | | | | a health risk. |
| pipework is exposed to view the combination of | | | | One final point to be borne in mind before you |
| plastic and copper (or stainless steel or iron) is not | | | | replace metal pipes with plastic ones is that plastic is |
| one that is very pleasing to the eye. | | | | a non-conductor of electricity. This means that |
| The advantages of plastic pipework | | | | all-plastic plumbing systems cannot be used to earth |
| The most obvious advantage is the lightness of the | | | | a domestic electricity supply. |
| pipework, which makes for ease of handling, but the | | | | You can obtain both polybutylene and CPVC tubing in |
| most important benefit is the ease with which plastic | | | | the 15mm (½ inch), 22mm (¾ inch) and 28mm (1 |
| can be cut and joined. This means that the level of | | | | inch) diameters commonly used in domestic hot and |
| skill you require to undertake a particular plumbing | | | | cold water supply and in small-bore central heating. |
| task is greatly reduced, as is the amount of time you | | | | However, in other respects - particularly as regards |
| require to carry it out. Both systems are also strong | | | | the flexibility of the two different typos of tubing |
| and durable, more resistant to frost than a traditional | | | | and methods of cutting and jointing - the two |
| plumbing system and, unlike the latter, not subject to | | | | systems differ. So, before you undertake a plumbing |
| corrosion. Last but not least, they are competitively | | | | task using plastic pipes and fittings, you'd do well to |
| priced. | | | | consider which system best suits your particular |
| Plastic pipes are less vulnerable to frost because | | | | application. |