What's A Cistern Doing In The Loo?
People travel for all sorts of reasons. For us, after working with American plumbing for years, learning about British plumbing was a natural extension of our interests. Since water heating is our primary focus, that’s all we were planning to study overseas. But other things grabbed our attention. We found toilets flush differently, strange drain lines poke out of buildings from unexpected places and odd storage tanks dwell in attics.
Terrific Toilets: Toilets were the most accessible piece of alien plumbing, and they were impressive because they work so well. (Their two-gallon flush has been the standard since World War II.) The ball valve (fill valve) is mounted on one side of the cistern (tank). Generally speaking, there is an overflow on the opposite side, which exits via an independent pipe. This may tie into the drain line through an air gap, or it may go directly to an outside wall and spill out onto unlucky bystanders.
The flushing mechanism is the best part. An upside-down “U” acts as a siphon. Pulling the lever forces a slug of water up the U, which starts the siphon. When the water level in the cistern descends to the base of the U, the siphon is broken and flushing stops. The nice thing about this is the unit cannot leak to the drain; the water waste we experience here with leaky flappers doesn’t exist there. (We found it interesting to see in an old Crane catalog from 1893 that a similar siphon mechanism used to be available in the United States.)
But what the British gain from their water-saving toilet technology is taken away by a lack of water meters nationwide. It’s true that the British countryside is lush and green, and frequent rain is a fact. But expanding population is putting a strain on water supplies, and causing more and more people to seriously consider water conservation.
However, water meters seem to be a new concept for residential use, and few places have them. Water is paid for by a flat fee based on the number and types of fixtures, rather than amount of water used. Leaky plumbing is rampant since there’s little motivation for repair. As a result, water meters could be as effective a conservation device in Britain as they are in the United States.
Plumbing Plums: In addition to our pursuit of plumbing, we were also tracking down good used book stores. Old books often have a wealth of marvelous information not available in current books. Imagine our delight in discovering a whole town devoted to used books! Hay-On-Wye, on the eastern Welsh border, provided a substantial number of volumes full of specific plumbing plums in the town’s 30–plus used book shops.
As we perused our purchases, we learned that lead water supply piping is quite common in Britain. But no one seems worried. There’s no hue and cry about the dangers of lead. The how-to books discuss how to tie into it, not how to remove it. Looking around, we judged the people there to be no balder or crazier than we are here (except, perhaps, when they are driving). It would be interesting to see a water quality study and compare actual lead levels in water here and there.
Water main distribution is also quite different. Houses have only a 1/2–inch supply line. That can’t provide sufficient water for multiple uses and is bound to be a bit of an annoyance. To get around the problem, a large, open, unpressurized cistern (storage tank) is installed in the attic. The reason for the cold water cistern is to provide storage for the house in the event of water main failure or widespread high water demand within a town or city. This cistern acts like a giant toilet tank. It has the same ball valve and overflow, and it can fill at its leisure.
As long as there is water in the cistern, delivery is much as it is here. That’s a boon to the water supplier, who can use a system that would otherwise be very much undersized and incapable of delivering water “on demand” as U.S. systems do. Cisterns generally hold 50 imperial gallons (60 U.S. gallons). That was originally about one day’s usage, so water delivery would seldom be interrupted.
Having an open tank in the attic does raise concerns about airborne germs and other undesirables getting into the water. The British solution is to run a pipe from the main line (before it reaches the cistern) to the cold side of the kitchen sink. This is the only truly potable water. Everything else is suspect. An attitude adjustment would surely be needed to get such a system accepted here. And how would you go about selling an upgrade to a potential client? “For only $$$ more, I can give you potable water in the bathroom, too!”
Stimulating Showers: Another result of having water supplied from an attic cistern is reduced pressure, so British showers are designed to operate on as little as 1 psi. If you don’t find that sufficiently stimulating, you can add a shower pump, which boosts pressure to the shower head.
Another shower alternative is the 240-volt “geyser” (pronounced “geezer”). This instantaneous heater shares the already cozy shower stall with you. Usually, one knob selects the desired level of heating (“none,” “low” or “high”), and another knob adjusts flow rate — which also affects temperature. As a result, once we got the water sufficiently warm, the flow was but a trickle. (Perhaps this water conservation technique explains the lack of water meters.)
One of our lodgings did have direct supply (without cistern) and a tank-type electric heater. The shower was strong and hot like most American showers. We were surprised and somewhat amused by multiple warning signs in the bathroom urging caution with what they viewed as an overly powerful flow.
So we learned that British methods of heating water are different from ours. Copper cylinders (water tanks) are the norm there. We didn’t find any glass-lined steel tanks. These copper cylinders hold about 25 imperial gallons (30 U.S. gallons). They’re covered with a rough foam insulation, and they may be heated with one or two electric immersion elements. (One of our “antique” plumbing books furnished this interesting description of how to add an element to a copper cylinder: poke hole in cylinder with a knife, trim hold round, insert threaded brass bushing, tin and wipe molten lead around joint and screw element into bushing — it’s that easy!) Cylinders can also be heated by a remote source such as a boiler or even an oil-burning kitchen stove.
In hard water areas, to prevent furring-up (liming), a tank-within-a-tank system is used for heat exchange. More often than not, heat exchangers, called calorifiers, are also used.
It’s not unusual for the task of heating water to be spread out among multiple appliances. Geysers may be used at taps, baths and showers. Washing machines and dishwashers may be supplied with built-in heaters. The need for a central heater and distribution piping vanishes with all these separate units.
Incidentally, scorched, burnt or blown air heating (AKA “forced air”) was not something we experienced in Britain. Hydronic heating is common, and it’s often connected with the domestic hot water supply. If such is the case at the inn where you are lodging, and if the owner is pinching his pence, the boiler may be fired up only briefly in the morning and evening to take the chill out of the rooms. Take your shower then, or you’ll be stuck with “lukecool” water later.
When the room radiators are hot, they’re very hot. You’ll see signs warning you against using them to dry towels or clothes, which could burn. The same goes for your backside. (And don’t expect the same sympathy for poor judgment that U.S. courts have shown.)
Lessons Learned: The British have learned to live with plumbing that has slowly evolved over a very long time. While some elements of British plumbing may seem substandard or even dangerous to us, the people there are just as likely to look askance at American plumbing. They may very well view it (as they do American roads) as being overdone, excessive, and extravagant. In the end, we imagine that if plumbing techniques and ideas from both sides of the Atlantic were freely exchanged and seriously examined, good things would come of it for all.