Heights of controversy: Does tallest structure in Sask. qualify as a building?

The Mosaic potash mining company thinks the above-ground portion of its mine in Esterhazy qualifies as the tallest building in Saskatchewan.

But the international authority on the ranking of tall buildings begs to differ.

The distinction lies between the definition of a building and a structure. Mosaic’s K3 headframe, which was built in Esterhazy as part of the potash mine, towers at least 113 metres above the prairie just outside the town about 180 kilometres east of Regina.

That easily makes the structure the tallest in Saskatchewan with no competition between Winnipeg and Calgary.

“Indeed Mosaic’s headframe is the tallest building in Saskatchewan

(and we do call it a building),” Mosaic spokeswoman Sarah Fedorchuk said in an email this week.

Not so fast, says Daniel Safarik, the editor-in-chief of the Chicago-based Council on Tall Buildings and Urban Habitat (CTBUH).

According to the globally recognized authority on skyscrapers, to be considered a building, instead of a structure, half of the facility’s height must be space that is

“designed to be safely and legally occupied by residents, workers, or other building users on a consistent basis.”

For example, Safarik pointed out in an email, Toronto’s CN Tower is not considered a building despite its height.

The potash headframe is a hoisting structure built above the potash mining shaft. Fedorchuk said people do work inside the K3 headframe, but could not provide details on how many and what portion of the concrete structure is regularly occupied.

The current title for Saskatchewan’s tallest building is held by another structure with Mosaic in its name, the Mosaic Potash Tower in Regina. The CTBUH considers the Regina tower a building and at 84.5 metres it ranks as the province’s tallest.

Nutrien Tower, which will house the Saskatoon operations of the other potash giant, is being built at River Landing as part of a massive hotel-condominium-office complex.

It’s expected to snatch the tallest building title from the Mosaic building in Regina when completed in 2021.