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Metrication and the UK Building Industry

The following is the text of an article written in October 1995 for Perspectives, a British magazine dedicated to traditional architecture and to the craftsmanship required for the preservation and maintenance of our built environment. The article was timed to coincide with the British Government's compulsory use of metric measurement for all goods and services in the UK, a legal requirement which is widely ignored and disliked by the majority of people.

The article is a reflection of the merits or otherwise of its use in the building industry where it has been compulsory for 30 years. For reasons best known to the editors, the article was never published. It would seem that their commitment to traditional values does not include that most fundamental of requirements in the construction industry; i.e. the practical use of measurements to transcribe drawings into real life buildings.

In 1965 the building industry decided to change to the use of French Decimal measurement, commonly known as the Metric system. Thirty years on and with the rest of industry now obliged to follow suit, perhaps it is time for a progress report. No one seems to have asked yet; has it worked? is everyone happy with it? is it easier, as the metricators claim, or is it harder? is it better than the traditional system or worse?

Working in the industry, I went along with this idea at the time without giving it much thought. In those days people still had faith in politicians and business leaders and believed that they knew what they were doing. Now that I have spent a number of years studying the history of architecture and of building, I have discovered how and why we arrive at the measurements we have always used.

The first and most striking thing about the 1965 change is that there has been no change. The industry carried on using and continues to use the same materials in the same sizes but with different unit values. Thus a brick is still 9" long but is now designated as 225mm. The standard door size remains at 6'6" x 2'6" but now has what appears to be a code number of 1981x762mm.

Why is this? Where are the materials/components which are whole units of 1 or 2 metres or natural multiples/divisions such as 250mm or 500mm? There seems little point in adopting a system of measurement whose basic unit is incompatible with the building process in terms of sizes required to build a house, for example, which is correctly proportioned relative to the size of the people who live in that house. After 30 years, it is apparent that the metric unit of 1 metre is too large and 1 centimetre is too small to be used comfortably in the building process. This is relevant in the rest of Europe too, by the way. Did you know that in Spain they still build brickwalls one foot thick (ladrillo de un pie)?

Those who know their history will know that the metre was invented in France in 1790 and is, allegedly, one ten-millionth of the distance from the North Pole to the Equator. The invention of the metre was part of the Revolutionaries' rational and scientific response to what they regarded as the superstitions of the past. By contrast, the British Imperial system (as used by the Greeks and the Romans as well as in pre-revolutionary France) is anthropometric which means it is based on the human frame.

From time immemorial units of measure have been derived from the human figure: palm, hand, foot, cubit etc. Some fall out of use and become archaic but those which remain do so for the very good reason that they are convenient, practical, easy to understand and, above all, easy to visualise which is a necessary part of translating working drawings into a built structure.

This was clearly demonstrated to me when I recently had a garage built. The workmen, all of whom were under 30 years of age were thinking and working in feet and inches - 18" deep foundations, 4" step etc. When any change such as that wrought in 1965 is mooted, nobody ever consults the real experts, the people who actually do the work. Where theory and practice do not coincide then theory is wrong and practice is right. Or to put it another way - in theory there is no difference between theory and practice, but in practice there is. Remember that according to aerodynamic theory it is impossible for a bee to fly!

It must be obvious to anyone who cares to think about it that an anthropometric unit such as the foot is preferable to a theoretical unit such as the metre. The metre, in fact, has had its official length changed no less than three times since 1790 (the latest being in 1965) and is currently deemed to be 1/299,792,458th of the distance light travels in one second. That's a real handy reference next time you are measuring a room for carpets or wallpaper.

The second aspect of the metric system is that it is based on the number 10 rather than 12. The superiority of duodecimals over decimals involves some esoteric reasoning which is too complicated to go into here but you may wish to refer to Plato's ideal cities of Magnesia (duodecimal) and Atlantis (decimal) and we all know what happened to Atlantis... Suffice to say that 12 can be easily divided into thirds and quarters whereas 10 cannot. (Ref 1. below)

The reasons put forward in support of metric are far from compelling. They range from the feeble (everyone else uses it) to the dimwitted (we have ten fingers for counting on). There has never been, to my knowledge, a logical demonstration of its superiority in use over traditional measurement. One of the most famous architects of the Modern Movement, Le Corbusier, used feet and inches to calculate his twin modular system of design after struggling and failing to work it out in metres and centimetres. (Ref 2. below)

Everyone I talk to is in agreement with the Prince of Wales when he calls for our towns and cities to be built on a human scale. This will never happen until we revert to a human scale of measurement.

Ref 1. For a fuller explanation of this theme, see
Constructing the Universe
by Michael S. Schneider

Ref 2. See also Le Corbusier's Modulor




10 nov 99;
1 sep 10