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How two different foot measures caused property chaos in the U.S.

Feb 1, 2020 | 2020 Toronto Star Property Law Column

By Bob Aaron
Toronto Star contributing columnist

Bob Aaron bob@aaron.ca

When it comes to real estate, most Canadians speak in terms of Imperial measurement. The majority of home offers I see show frontage and depth measurements in feet, even though we officially switched to the metric system during the time of the first Prime Minister Trudeau.

Condominium listings usually show the size in square feet, while building materials, like the two by four, and the four by eight plywood sheets, are measured in inches or feet. Flooring is typically measured in square feet.

So it came as a huge surprise to me recently to discover that there were two common definitions of the 12-inch measurement known as a foot, and that the U.S. foot is slightly longer than the international foot. After a 60-year period in which both measurements were in common use south of the border, the United States has announced that it is giving the boot to its old official foot.

The story began back in 1893, when the U.S. government officially defined a foot as 1,200 metres divided by 3,937. The resulting length is 0.3048006 metres.

In 1933, the international foot was agreed to be 0.3048 metres, and the last three digits were lopped off.

This caused problems in measuring large dimensions, so in 1959 the American government started the switch to the international foot, but allowed surveyors a temporary reprieve.

Now, after more than 60 years, the National Oceanic and Atmospheric Administration (NOAA) and the National Institute of Standards and Technology have announced that the country will officially switch to the smaller foot in 2022.

Why is this important? It seems that surveyors in 40 U.S. states use the larger U.S. foot, while the rest use the smaller one.

The difference is about an eighth of an inch per mile. The measurement of the width of the entire United States is 28.3 feet wider using the international foot instead of the U.S. survey foot.

The result is chaos, according to Michael Dennis, a project manager for the National Geodetic Survey. He quoted a story from a fellow surveyor about a contractor in a state which uses the U.S. foot. It had planned a building in the glide path of a major airport in a state which uses the international foot.

Although the difference between the two definitions is small, it caused trouble during bridge work between Oregon, which sticks to the international foot, and Washington, which uses the U.S. foot.

With the world facing challenges from global warming, floods, fires, viruses, disease and widespread hunger, it’s nice to know that at least one tiny world problem is finally about to be solved.


Contact Bob Aaron

Bob Aaron is a Toronto real estate lawyer and frequent speaker to groups of home buyers and real estate agents.
He can be reached by email at bob@aaron.ca, phone 416-364-9366 or fax 416-364-3818.

Aaron & Aaron specialize in Real Estate Law, specifically Sale of Rental, Condominium, Residential, Rural Recreation, Offer to Lease, Commercial, and New Construction

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