Eco-friendly ‘plyscrapers’ are on the rise.
Timber skyscrapers (Plyscrapers) are being built all over the world.
Ever since the 10-story Home Insurance Building in Chicago was called the first “skyscraper” in 1885, architects have been striving to create ever-taller buildings.
Ten stories quickly became 20, 20 became 50, and on and on. In 2009 the 830m Burj Khalifa in Dubai became the world’s tallest building.
A plyscraper is a high-rise building built with panels made of cross-laminated timber (CLT). These modular sheets are made from cheap, sustainable softwood that are glued or pinned together in layers — a bit like super-strong, super-thick plywood.
While the raw material might vary in quality, CLT (also known as mass timber) is engineered to be stronger than concrete. CLT panels resist earthquakes and even fire, charring instead of catching alight like the lumber in typical homes.
Plyscrapers can be bolted together in days, and they require a fraction of the labor use to erect traditional steel-and-concrete high-rises.
Timber skyscrapers are much quicker to build as even steel skyscrapers have concrete floors which can take weeks to dry. That’s several weeks per floor. On the other hand wood panels can be sliced to exact dimensions in the factory and then slotted into place within a matter of hours.
Then there’s the issue of weight.
For a long time Murray Grove, a nine-storey housing block in Hackney, was the highest in the world. “If we’d made it from concrete it would have taken 900 HGVs [heavy goods vehicles] rumbling through London to deliver all the material,” says Anthony Thistleton, a founding director of Waugh Thistleton Architects who designed the building. In the end it took only 100.
That’s not to mention the environmental benefits. Though we don’t tend to think of the carbon footprint of our buildings, concrete and steel are secret super-villains, thought to be responsible for about 8% and 5% of global emissions respectively. On the other hand trees actively suck in carbon dioxide and lock it away in their wood.
Today wooden skyscrapers are sprouting up across the globe, from Norway to New Zealand.
There’s the 18-storey T3 project in Minneapolis, made from pine felled by mountain pine beetles, a tiny insect pest that lives in their bark; the €60m (£44m/$58m) HoHo tower, a sleek spruce confection currently under construction in Vienna; and the lofty 133m (436ft) Trätoppen proposed for Stockholm. Translating as “the treetop” in Swedish, it would sit on top of a 1960s carpark.
“You don’t need an experienced master carpenter to do this,” says Casey Malmquist, founder of Columbia Falls, Montana-based SmartLam, one of only two CLT manufacturers in the U.S. “It literally goes together like Lego.”
But mass timber’s greatest benefit may be that it’s environmentally friendly.
“For me, the driving factor is the impact of building with a renewable, sustainable, carbon-storing material.” Casey Malmquist
High-Rise, Low Pollution
The U.S. Department of Agriculture (USDA) agrees. It cites estimates that even a four-story building made of mass timber would save emissions equivalent to taking 500 gasoline cars off the road for a year.
This is because concrete emits nearly its own weight in carbon dioxide during production.
So when a plyscraper goes up, that carbon is locked away for decades. And when the building is finally torn down, the wood can be recycled or burned for energy.
“We have a very compelling argument, and a consensus with environmental groups, that sustainably managed forests give a product that is going to have significant impact on climate change.” Casey Malmquist
Canada is the epicenter of ambitious CLT projects, thanks in part to Vancouver-based architect and mass timber evangelist Michael Green.
Green has built several large mass timber buildings, including the seven-story T3 building in Minneapolis and the eight-story Wood Innovation and Design Centre in Prince George, British Columbia. And he’s working on a 35-story wooden mixed-use development in Paris, called Baobab.
He welcomes competition to reach for the sky. “You say 30 stories, I say 42, and soon it’ll be 46,” Green said. “The momentum is enormous. It’s a positive spirit of competition that spurs all of us on.”
SmartLam has provided CLT panels for an Amtrak station in Tacoma, Washington, two mass transit centers on the East Coast, and many agricultural and residential properties.
“As builders, developers, architects and engineers dip their toes in the water, we’re seeing that projects naturally growing, both in scope and scale.” Casey Malmquist
We didn’t invent building timber skyscrapers. The Sakyamuni Pagoda of Fogong Temple in China is one of the world’s oldest wooden structures.
It was built by Emperor Daozong of the Liao Dynasty and it is still standing nearly a millennium later. It is 67m (219ft) high and was until recently the tallest timber building in the world.
It has survived at least seven earthquakes including one in 1556 that killed almost a million people.
Wood is inherently flexible. Timber structures tend to sway without breaking.
For thousands of years, wood was usually the only building material available. In the UK medieval houses, offices, forts, cathedrals and even castles were built out of timber. Green timber is amazingly resilient. It does not rot unless you get it wet.
“If you can keep it dry it will last forever.” Andy Buchanan, PTL Consultants
If you need some reassurance about fires there is a study by the Committee on Tall Wood Buildings. The test was carried out at the Fire Research Laboratory, Virginia, USA. When two one-bedroom apartments were set on fire they found that although initially the fire raged and burnt through furnishings, it then extinguished itself. The structure charred, but remained intact.
One of the key factors is what happens to Cross Laminated Timber (CLT) when it is heated. It beats steel and concrete which tend to melt and weaken.
“There’s an image that we often use in our lectures. It’s a devastated fire site with a big timber column supporting a timber beam. At the top is a steel beam that’s completely melted.” Anthony Thistleton
The main concern for most skyscrapers is their sheer weight
The material tall buildings are made of have to be strong enough to support their bulk of the structure or they will collapse.
As timber buildings are so light the main challenge is holding them down rather than up. The higher you get the stronger the wind is. At the top of the Burj Khalifa wind can reach 150kph (90mph).
CLT can be cut to shape and slotted together like lego during construction. This means that building is much more rapid than conventional brick, steel and concrete construction. Brock Commons in Vancouver was built in seven days and cost the same as a conventional concrete building.
Wooden buildings have better environmental credentials. At Murray Grove in London, people are not using their heating because wood is such a good insulator.
“The 20th Century was the concrete age, it was all about the dominion of man over nature. Now we’re transitioning towards a different attitude, a more nurturing one.” Anthony Thistleton
The important thing to remember is that just one cubic metre of wood sequesters a ton of CO2.
Plyscrapers are here to stay.
I love Architecture. I think it’s vital to talk about all aspects of Architecture — whether it be planning, construction, design or green building. I have written 3 E-Books & over 110 articles. Please feel free to let me know if you have any queries regarding architecture, planning & construction & I will assist you.
I am originally from the UK and moved to South Africa in 1999. I started Blue Designs in 2004 after working as a driver for Avalon Construction on a luxury home in the Featherbrook Estate. In my spare time I am an artist and writer (The Naked Architect).
Phone- +27 82 399 0180
Email — clairecardwell@gmail.com
Website- www.bluedesigns.org
Follow me on:
https://www.linkedin.com/in/claire-cardwell-ab438a17
Other Articles I have written include :-
https://medium.com/the-naked-architect/will-the-leaning-tower-of-pisa-fall-over-d9488f24fefd
https://medium.com/the-naked-architect/copycat-architecture-is-booming-in-china-87b2f4b9f628
https://medium.com/@clairecardwell/green-buildings-are-healthier-5ed1471344b2
Sources :
https://www.proudgreenbuilding.com/news/eco-friendly-plyscrapers-on-the-rise/
#architecture #architects #architect #architecturaldesign #sustainability #ecofriendly #environmentallyfriendly #climatechangemitigation #timberbuildings #woodenbuildings #plyscraper #plyscrapers #clairecardwell #clairelcardwell #thenakedarchitect #nakedarchitect
