Name: Will we all live in 'plyscrapers' in the future? | BBC Ideas
Uploaded: 2021-06-03T17:50:05.000Z
Duration: 4 min 21 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

Horyu-ji Temple is the world's oldest surviving wooden building.

Five storeys high, it's still standing firm

despite being made from cypress trees felled over 1,400 years ago.

And Horyu's great age reveals a message for our future -

building with timber can be durable, beautiful and practical

and it can even help tackle climate change.

If we made 90% of our new buildings from wood

we could reduce our global carbon emissions by 4%.

That's more than the total climate footprint of flying.

So why does building with wood do such good?

First, trees absorb carbon dioxide from the air as they grow.

This is naturally stored in the beams and panels of buildings,

contains CO2 absorbed from the planet's atmosphere

Of course, using wood means felling trees,

but so long as you're not chopping down ancient forests,

you're maintaining the wildlife, replanting,

and putting wood to long-term use, it's sustainable.

In the last 15 years, in the northern Hemisphere

total forest cover has increased by an area of around 242,000 sq km,

In fact, every seven seconds the sustainable woodlands of Europe

yield enough timber to build a four-person family home.

Canada can harvest enough trees every year to house about a billion people.

An equally important carbon reduction comes from what you're not using -

construction with natural materials demands far less concrete and steel

Steel-making accounts for around 8% of total global CO2 emissions

OK, not all of this is going into buildings,

It's the combination of stored carbon and avoided emissions

that really tips the climate scales for timber,

and a recent innovation has made wood much more user-friendly.

is made by layering conifer planks at 90 degrees to each other

in three to seven tiers and then gluing them together

These panels are suitable for walls, floors, roofs, even lift shafts.

and their strength-to-weight ratio is often better than concrete.

CLT can be used in schools, offices and warehouses

with 85m 'plyscrapers' recently completed

So why are wooden buildings still the exception?

Mainstream construction is a risk-averse industry

One approach is law - the French government has decreed

that at least 50% of every new public building must be made of wood.

This not only allows those structures to store more carbon

but also encourages a generation of builders

But how safe are wooden buildings, you may ask?

that gutted the medieval centre of London in 1666?

have shown they tend to form a charcoal layer

and when combined with heat-resistant glues and claddings

they can match or exceed the fire resilience of conventional buildings.

can actually lower the heart rate of pupils.

Even looking at a wooden wall can reduce blood pressure.

So wood is not only renewable, safe and climate-friendly,

Or to put it another way, using wood is really good.