Norway’s “The Tree” tops list—for now
A 14-story apartment block in Bergen is the world’s tallest wooden building at 167 feet
M. Michael Brady
The use of wood as a building material has long been marginal in today’s steel and concrete cityscapes. That may soon change, in face of a renaissance in wood building technology driven in part by environmental concern. A building finished last December in Norway may well mark the turning point.
The longevity of wood as a building material is nigh legendary. Hōryū-ji, literally “The Temple of the Flourishing Law,” in Nara Prefecture, Japan, is among the world’s oldest, if not the oldest known wooden building. Erected in the year 607, it has withstood weather and earthquakes for 14 centuries, the peak of its 32 meter (105 ft.) pagoda intact.
In Norway, the Heddal Stave Church, built in the early 13th century at Heddal in Nottoden municipality in Norway, was long the country’s tallest wooden building, with an overall height of 26 meters (85 ft.). It held that record for more than seven centuries, until last December, when a 14-story apartment building named Treet (The Tree) was finished in Bergen, its 62 apartments ready for occupancy. With an overall height of 51 meters (167 ft), Treet became not only Norway’s, but also the world’s tallest wooden building.
The choice of a wood structure resulted from the goal of its owners, the Bergen og Omegn Boligbyggelag (Bergen and Surroundings Cooperative Building Society) to build a cost-effective, sustainable building. Aside from being a sustainable building material, wood has an advantage of light weight; a wooden building weights about a fourth as much as an equivalent structure of concrete and steel, so its foundations may be correspondingly smaller, a significant factor for the location of Treet at the waterside, near a bridge.
Treet consists of modules stacked together using technologies developed for wooden bridges and smaller prefabricated wooden buildings. Each module essentially is a large passive house. Concrete slabs were included at two levels to add weight and keep the building from swaying. The exterior was clad in metal and glass to protect the wood structural elements from rain.
Treet’s world record height of 167 feet will soon be surpassed by seven feet, when the 18-story, 174 ft. high wooden-structure student housing building now being built at the University of British Columbia in Vancouver is finished in early 2017. And both the UBC student housing building and Treet may soon be dwarfed if the height record is returned to Scandinavia by the building in Stockholm of a 40-story, 436 ft. high proposed wooden structure apartment building, appropriately named Tratoppen (The Tree Top).
M. Michael Brady was educated as a scientist and with time turned to writing and translating.
This article originally appeared in the Oct. 7, 2016, issue of The Norwegian American. To subscribe, visit SUBSCRIBE or call us at (206) 784-4617.