Plumbing and Cold Water Supply

Water Supply

Have you ever wondered where your water is coming from? If you live in England or Wales, the water in your tap comes from several different private water companies. Some of these companies can be seen as the successors of regional water authorities, also providing us with sewerage services. In Scotland, on the other hand, water is supplied by a fewer number of national water companies. Nowadays we tend to be charged for water in accordance with our consumption but this was not always the case.


Cold Water Supply

So, how does the water end up in your tap? Well, water travels to your house via the water mains and these are generally run down your local roads. Each individual property will then have its own branch service pipe and these are fitted with a stop-valve. This particular stop-valve is commonly known as the ‘water company stop-valve’ and they are normally found just outside your property boundary. This valve can be located under a small metal cover by the pavement if you live in a town, while it might be a bit trickier to locate it if you live in a more rural area. If you need the mains turned off, you will normally have to contact the water company and they will send out one of their engineers with a special key. The service pipe goes from the water company’s stop-valve to your house and it has to be buried at least 750 mm under the surface in order to avoid frost damage. It can often be found inside a drain pipe in order to protect it from damage and it should rise slightly so that air bubbles can be avoided. The service pipe leads to the property’s own main stop-valve and it is from this point onward that the property’s own supply starts.

Cold Water Stop Valve

Water Pipes

As a home owner, you are responsible for the supply pipe as well as the entire domestic distribution system. In older houses, the mains and service pipes were made of galvanised lead or iron but nowadays they tend to be replaced by either copper or plastic pipes. When the pipes were made of galvanised lead or iron, the pipes had another purpose as well. They were used to provide an electrical earth connection to homes. Since plastic pipe started to be widely used to transport water, electricity companies are now using their own earthing terminals to provide electricity to homeowners.

Different Types of Valves


There are many different kinds of valves but when it comes to plumbing it is mainly four different ones that are used. These are called drain-valves, gate-valves, servicing valves and stop-valves. You can find them fitted in both hot and cold water supplies and they are used to cut off water from the entire system or if needed, just from individual branches. In this article I will tell you a bit more about two of these valves.


Some valves can fully restrict the flow of water but gate-valves only have the capacity to restrict it slightly when opened. Therefore they are usually fitted to cold supply pipes. You can find them along pipes going from a cold water cistern as the water pressure is lower there. The control mechanism of many gate-valves is typically a solid gate (or portcullis) which is lowered to cut into the water flow when screwed in. Most gate-valves are fitted with wheel-handles and they have to be opened completely open to avoid creating airlocks. They normally come with compression fittings and can be fitted way round. If you come across cold supplies from a cold water cistern that is not yet fitted with gate-valves, you can easily sort this out as it only requires a short length of pipe to be cut out. Rather than having to drain the cistern of water, you can use a cloth and polyethylene sheeting. Bung this up and place it against the outlet. By turning on the taps, the ‘bung’ should seal o the opening. If this does not work or if you so prefer so, you can always use a drain-easy-kit.

Gate Valves

Servicing Valves

The water regulation stipulates that servicing valves should be fitted on pipes leading to ball-valves, or so called float-operated valves, on cold water, feed-and-expansion-cisterns as well as WCs. Most servicing valves that you come across should have a small ball fitted internally with a whole through it and this is so that a quarter turn is all that is needed to fully open or close the valve. This is operated by a small circular knob or by fitting a screwdriver into the slot. Service-valves used for installing washing machines generally have a tee fitting and a lever. It would be advisable to fit servicing valves before every single tap to allow them to be rewashered without having to drain the entire pipe and possibly also the cistern. Always leave a job in the same good state as you want to find your next one in. Best of luck!

Plumbing Valves

Taps and Tap Issues

Taps and Valves

As a plumber you know how important taps and valves are to the plumbing system and it is important that all parts work as well as possible. All parts need to be kept in a good working order to avoid water leaks and therefore possible water damages to your home. It is also important that you can turn off the water if you need to, for an example if you happen to have a leak. One of the most common reasons for a call out as a plumber is a water leak. The reason for this can differ but it is often due to a packing or gland failing or due to a worn washer.

Bathroom Taps

Glands and Packings

A packing or gland failing is basically when there is a leak from the top of the tap whenever it is open. A good thing is that a packing can easily be changed without having to turn off the water but you will have to remove both the tap head and the ‘easyclean’ cover in order to do so. If you come across an older style of cross heads and have trouble getting it off, even after removing the grub screw – try tapping it gently with a hammer. If this still does not work, open the tap completely and unscrew the easyclean cover and place two small pieces of wood underneath it, before tightening the tap with the head down. Sometimes the ‘easyclean’ cover is easy to remove and sometimes it is trickier. The thing to remember though is to always protect it with a small piece of cloth if you are forced to use any tools to shift it. Sometimes it helps to pour boiling water on it in order to shift it. You can replace traditional packing with wool covered in petroleum jelly. If you come across the more modern non rising spindle taps, you can easily change the rubber O-ring seals when needed. If a mixer tap is leaking at the base of the swivel nozzle, you can be sure that the O-ring or the washer needs replacing.

Plumbing Glands


A warn washer means that there is a leak from the actual spout rather than the tap and this happens when the tap is closed. How you go about changing the washer depends on what type of tap is in use. I would always advice you to keep a few spare tap washers to hand and make sure they are replaced regularly. If the washer and jumper cannot be separated you will have to replace both. You will generally have to turn off the water if you are replacing tap washers – unless it is a ‘Supatap’. As with many other things, tap washer comes in different designs and sizes. If the washer is of a brand name, the smooth side needs to come into contact with the seating. If the actual tap has gone or if the valve seat has gone, it can be re-cut or you can insert a replacement seat of nylon. This cannot be fitted to ‘Supataps’ though.