Original subtitles

Narrator: What happens when an ambitious builder

tries to join two skyscrapers

high up in the Manhattan skyline?

Man: You can't call a friend and say,

hey, what did you do the last time you built a bridge

300 feet in the air in New York City?

Narrator: How does this huge wing-like roof

not take flight in Gale-force winds?

Man: The whole canopy has an ability to move

15 to 20 centimetres.

Narrator: And how can a building be constructed

without a corner in sight?

Woman: It kind of goes against

everything we think engineering should be.

Narrator: This is the age of the extraordinary...

Man: This house always is on the verge of falling down.

Narrator: Where ingenious engineers

have unleashed unchecked creativity.

Woman: Everything in this building

pushes at the boundaries of what's possible.

Narrator: Building structures so outrageous,

they defy logic.

Woman: The forces on this thing

look like it should be torn apart.

Narrator: Now their secrets are revealed...

Discovering the incredible stories

of their construction...

Woman: These are extraordinary feats of engineering.

Narrator: To try and understand

how did they build that?

New York.

With the total area of buildable land

worth over $1.7 trillion,

its eye-watering prices

have created one of the world's most memorable

and expensive skylines.

With space at a premium,

it's forcing developers

to come up with groundbreaking solutions

to make the most out of even

the least inviting scraps of land.

Developing one awkwardly shaped plot in midtown Manhattan

tested engineers to their limits,

leading to panic on the streets.

Man: You hear the fire department,

they pull up and the guys come screaming, running in.

"We got a call.

One of the buildings is falling down!"

Narrator: And creating the city's

first skybridge in 80 years,

giving rise to one of New York's most incredible new skyscrapers.

This is the American copper building.

Ellie cosgrave: Building two skyscrapers,

wanting to join them in the middle,

and then deciding that actually you want them bent...

That is next level.

Narrator: In 2013, developer Simon koster

had his eye on a plot next to the river

that should have been prime real estate.

But the site came with a major problem...

New York City's zoning laws,

the rules that decide what can be built and where.

Simon koster: The zoning of this site was prescribed

before we bought the site.

That approval prescribed

the exact footprints of the tower

and the exact heights of the tower.

They assumed, by prescribing the footprint and the height,

that they were prescribing the exact building shape,

but when we bought the site,

we didn't want to create two buildings.

We wanted to create one building.

Narrator: There was an existing building

in the corner of the plot

and a piece of land that had been zoned as a park.

So how could they create

their dream of a single building?

Simon: We didn't want anyone to be going to the gym

in their neighbor's building,

we didn't want someone going to a lounge

or going to visit someone else in a neighbor's property.

We wanted to use the scale of the property and the block

to create one community.

Narrator: Koster brought in Greg pasquarelli

from shop architects to find a solution.

Gregg pasquarelli: When our client bought it,

he said, I could go through a rezoning,

which takes many years

and has a lot of risks and is very difficult,

or he said,

can you come up with something with these handcuffs on?

And that was our challenge.

Corina kwami: They could have built two towers,

but they came up with a much better idea.

Simon: There end up being a lot of great ideas,

a lot of terrible ideas.

And what usually ends up happening

is one of the terrible ideas

turns out to be a really wonderful one.

And it's terrible at first because somebody says, you know,

let's build a giant bridge between two buildings

hundreds of feet off the ground.

And for those of us that have to pay for it

and figure it out,

we go, no, let's not do that.

Um, but of course, as you start to wrap your head around

kind of all the different aspects

that could make it possible,

you start to realize that it's actually very approachable,

and the way we approach building the skybridge

was the same way we approach building everything else,

which is kind of one step at a time.

Narrator: It would be the city's first skybridge

in over 80 years.

Joining two giant skyscrapers almost 300 feet in the air

on the banks of the east river on a site prone to flooding

was always going to be an engineering headache.

But it was also an opportunity.

Gregg: The idea was we could make a sort of amenities package

or a shared space

that would be sort of typical for each building,

or if we built a bridge,

we could build one phenomenal one

that brought everybody together.

And so getting that designed and built

and making it work

was the greatest challenge,

but I also think is the greatest success of the project.

Narrator: The easiest way to connect the two towers

would be with a straight line.

But that would mean going over the existing building,

which they didn't own.

The architects came up with a gravity-defying solution.

They decided to bend the buildings.

Ellie: How did they bend the towers?

That's the real question.

Simon: They bend towards each other, right?

One on the long axis and one on the short axis.

It moves the edge of the west tower

out to the corner of the property line

so that we can actually connect the two buildings

with a straight line.

Otherwise our bridge would have had to be kind of l- or v-shaped

which is obviously much harder still to do.

Narrator: By bending the two towers,

they'd not only overcome the zoning issues,

but also the engineering ones.

Hayley loren oakes: Making small adjustments

is a great way to make a big change.

A couple of inches can quickly become meters,

and it's something that clever designers

can use to their advantage.

Narrator: And that's exactly what they did here.

By slightly moving each floor closer to the other building

as they go up to the skybridge,

and then moving away again,

they were able to bend the buildings.

Simon: We were able to solve both of those problems

with these really elegant architectural moves.

Narrator: In 2012,

work began preparing the site for construction.

It was clear from the start

this was going to be a tough build.

The site was right next to the east river,

a location that had previously flooded.

@joshua macabuag: It's in an area that's subject to hurricanes,

and so in 2012, there was a very large hurricane,

hurricane Sandy, which affected New York,

and during that hurricane

this actual site was flooded

before the building was constructed,

so that's really highlighted

two of the main risks to the construction...

The wind and the water.

Narrator: The man who had to face this challenge

was Michael Jones.

Michael Jones: The foundation of the building

was kind of a monster process on our end to build it.

We're very close to the east river,

and the water level is very high.

So to dig a hole as deep as we had to dig it

into our foundation elements

was a serious challenge.

Narrator: Michael and the team had to dig down almost 50 feet.

With the water table only 4.5 feet below the surface,

they needed to stop the site from flooding.

The engineering solution was to create a huge concrete structure

to keep the water out.

Michael: What you do is you create a perimeter wall

around your site from the ground level.

You can push steel sheets, push those down into the ground,

and they interlock,

and so you more or less build a bathtub with no bottom,

and then the water level inside the bathtub

is the same as it is outside.

So then what you can do is you drill Wells down there

and you De-water inside of your bathtub.

You can locally bring that water level down

by putting a pump.

You have to kind of artificially drop the water level,

and to do that with, you know, a few cups of water

is really easy.

To do it with a few million gallons is difficult.

Narrator: It took a year and a half to do it,

but with the bathtub built and the foundation in,

they could turn their attentions

to the next big engineering challenge...

Building the bending towers.

Joshua: Generally, a leaning building

is very much a bad sign,

and the designers

would very much have had to have factored in

the kind of sideways forces that are caused by something leaning.

But there's two things to consider,

and that's they've designed a building that's able to lean,

but also that that building

is going to be leaning throughout it's construction,

which means you have to really think about

the stability of the final building,

but also all the intermediate stages during construction.

So it's an engineering feat.

Narrator: The person making sure

this bent skyscraper didn't come crashing down

was structural engineer Susan hamos.

Susan hamos: Because of the leaning of the building,

every floor we had to tie back to the shear walls.

What shear walls means, they take shear,

they take horizontal load,

they take shear from the wind load,

shear from the seismic loads,

and shear from gravity loads.

You imagine, if you put something like this,

it wants to fall down.

So we had to put some rebars to pull it back to the vertical,

long concrete walls

that were designed to take all these horizontal loads

from the gravity.

Narrator: Although the building bends,

the lift shaft and the shear walls

stay vertical

and act like a spine,

taking the force of the floors

as they create the bending skyscrapers.

Michael: The main structure,

which is the core, the elevator core

and the shear walls, which are massive structures,

those stay straight.

But all of the columns were on an angle.

So we got really good at building columns on an angle.

Narrator: As the extraordinary skyscrapers

took shape on the Manhattan skyline,

they didn't go unnoticed.

Michael: This tower, the east tower,

goes about 8.5 inches per floor.

So by the time, you know, we are really offset maximum distance,

we're over 20 feet, 22 feet, I think it is,

out of plumb

before we start working our way back.

And that's the sort of visual thing

that people really weren't accustomed to seeing.

Hayley: The bent shape of the skyscrapers

caused panic as the buildings were going up,

which is something that the main builder had to deal with.

Michael: One day, you know, we're down there,

we're all working,

and you hear the fire department,

they pull up, and the guys come screaming

and they're running in, and it's all chaos for a second.

We're trying to figure out what's going on.

Finally I grabbed the guy. I go, "what's going on?

What's happening? I'm in charge here.

What's going on?"

He said, "we got a call.

One of the buildings is falling down."

And I kind of kind of stopped,

I had to think about it for a second.

I go, "no, no. It's supposed to be like that."

We showed him pictures and renderings of the building

and showed him the plans and everything,

but it's such a unique architectural feature

that people didn't know how to respond to it.

Narrator: Once the builders had convinced new yorkers

that the towers weren't collapsing,

they still faced one of their biggest challenges...

The skybridge.

Central to the design,

the skybridge nearly 300 feet in the air

would join the two towers together,

making one community.

Michael: The bridge is several layers.

There's private terraces on top,

there's a public lounge,

in between there's a pool and hot tubs.

You can kind of swim from one building to another.

And then below all that, the bottom level of the bridge

we use to transfer mechanical water

and we use emergency generator power.

We transfer from one building to another.

And that's really my favourite part,

is it allows us some kind of leeway

in terms of where we put equipment

so each building doesn't act isolated to each other.

Narrator: The bridge came with

some serious engineering challenges.

How would they stop the hurricanes

that regularly hit New York

from tearing it apart?

Simon: The biggest design constraint

on tall buildings in New York is wind,

so buildings move back and forth,

towards each other and away from each other.

The total movement between the two buildings

is about 12 inches.

12 inches is in a windstorm,

so that movement was our number-one challenge.

From a structural perspective,

that skybridge is like putting a toothpick between two rocks.

Narrator: Skyscrapers are built to cope with high winds,

and at the top, can move about 3 feet in any direction.

Fine when they're not fixed to another building.

But here, two independently moving towers

would be linked by the bridge.

And when they moved, they could rip the bridge apart.

Susan: Is it possible to put the bridge there?

We said, of course it's possible.

So how would we do it?

And we said no problem,

we'll connect it to one building,

and we let it slide on the other.

So when the wind is hitting the two buildings,

one would move out, the other one would move in.

And we don't want the bridge to like buckle,

to pop out of its place,

so we have to slide it on one side.

Narrator: Their solution

was to join only one side of the bridge to the towers

and balance the other side on huge teflon plates,

letting the bridge slide in and out of the east tower.

Michael: It slides on these giant teflon plates

that account for 28 inches of movement in total,

14 in any given direction.

Narrator: Now they knew it was possible.

All they had to do was build it.

Michael: Unfortunately,

when you're doing something unique like this,

you can't call a friend and say,

"hey, what did you do

the last time you built a bridge 300 feet in the air

in New York City?"

Narrator: Building a 300-foot high and 240-foot wide

scaffold tower between the buildings

to allow construction of the bridge

would be difficult.

So they decided to build a temporary bridge,

from which they'd construct the real one.

Michael: We were trying to figure out

the best way to do it,

and it started with someone was supposed to bring a football in,

and we were going to tie a string to it

and kind of throw it from one building to another.

But I think we forgot the football that day,

so we took a stick and wrapped it up

with a bunch of literally small string,

made sure everything was clear below,

everything was safe, we were good.

Threw it from one building to another,

and so we had one string.

Then we pulled back a string that was a little thicker.

Then we pulled back a rope,

then we pulled back a thicker rope,

and then we could finally pull back the steel cable

and literally just started weaving the cable

back and forth and back and forth

until we got it.

From there, we could work off there

and start building the bottom of the bridge,

build another platform,

build the next level of the bridge, and so on.

Narrator: With the temporary bridge in place,

Michael then had to figure out

how to lift the huge sections of steelwork

300 feet into the air.

Michael: We were limited with what equipment

we could actually lift it with,

because, as you can imagine,

lifting something very heavy, probably 40 to 60 tons,

at that height, over 300 feet in the air,

requires a serious piece of equipment,

and you can't always fit a serious piece of equipment

in New York City.

Hayley: To lift the giant steel trusses,

the skeleton of the building into place,

the builders attached a tower crane

to the skyscraper

to stabilize it against the wind.

Michael: Now that we know the maximum piece of equipment

we can get in here,

how do we break the bridge into pieces

that that piece of equipment can lift

and so that we can then construct it?

Narrator: 200 tons of steel

had to be hoisted up 300 feet one piece at a time,

to where construction crews could connect them.

With the skybridge in place,

work began on fitting the extraordinary copper facçade.

Ellie: They're called the copper buildings

because they're covered in over 4 million pounds of copper.

Narrator: Like everything else on this project,

creating that copper finish was not going to be easy.

Simon: The first time this idea was presented,

we thought we'd have to put copper plate

on the outside of the building,

and we did the math on how much copper we'd have to buy

and then looked at the raw material price of copper,

and realized that we'd have to pay more for the copper,

just to get it here,

than we paid for the property itself,

which means that we couldn't afford it.

And so what we ended up doing

was coming up with a pretty unique laminating structure

where the copper face,

which is very, very thin copper foil,

actually thinner than what's even on a penny,

and it is laminated to a fireproof core,

and then on the backside of that core is stainless steel.

Narrator: The raw copper is then left untreated

and open to the elements.

Michael: The copper's gone from shiny penny colour,

and it will patina and continue to turn green.

Narrator: The rest will be done by the weather

over the next 50 years.

Michael: It's going to be beautiful.

I can't wait for that.

I love the copper,

but there's something very American

about that colour green,

especially in New York.

It reeks of kind of old beautiful New York buildings,

all the flashing,

but ultimately it reminds me of the statue of Liberty,

so can't wait for it.

Hayley: The designers and developers

have truly built the incredible from the impossibly difficult.

Narrator: The American copper building

takes its place in the New York skyline

as a testament to how

ingenious engineering and clever design

can create amazing living spaces

in one of the world's most crowded areas.

Joshua: Two spectacular buildings

forming a single iconic project...

It's a real engineering achievement.

Gregg: Taking this kind of restrictive set of rules

and celebrating it

into something that looks beautiful and inspiring

and makes people wonder about it...

Whenever you can do that as an architect,

I think that's something you should strive for.

Narrator: 5,000 miles from New York,

in the ancient city of Athens, Greece,

engineers and architects have been battling mother nature

to create an enormous 100,000 square foot floating roof.

Man: To my knowledge,

it's the first application in the world.

Narrator: Over half a billion Euros

created a cultural centre for all athenians,

complete with a new hill, with a public park on top.

Hayley: This isn't just about creating a building;

you're creating geography.

Narrator: And all of which has to be tough enough

to withstand any potentially devastating earthquakes

woman: Building in an earthquake zone

is a dangerous game.

Narrator: So how did they build it?

In 2006, the stavros niarchos foundation,

a wealthy philanthropic organization,

wanted to give a new home

to Greece's national opera and national library.

They wanted somewhere that would inspire the people of Athens.

Elly andriopoulou helped manage the 566 million euro Grant

given to the stavros niarchos foundation cultural centre.

Elly andriopouloi: Pushing the boundaries

@of architecture and engineering

wasn't a goal in itself,

but it was a very important means

to achieve the vision of the sncc.

So we didn't want to just provide new premises

to these two national organizations;

we wanted to give them a new home,

which would become a landmark.

There were a lot of risks taken.

The people involved in the project

were very passionate about pushing these boundaries,

and they certainly had the expertise to do so.

Narrator: The foundation turned to the company

that had transformed the London skyline

with the shard,

the renzo piano building workshop.

Giorgio Bianchi oversaw the project.

Giorgio Bianchi: We had in mind

this idea to raise the land in some way

and hide the opera and the library

under something like a hill.

The hill was a park.

I create my hill,

and on top I put the solar canopy.

And then I plant my park.

And here you have...

The opera house and the library.

Easy!

Narrator: Building it would prove to be anything but.

The futuristic buildings would hide behind a massive

100-foot-high artificial hill.

At one end, the new earthquake-proof complex

would be home to the Greek national library

and the 300,000-square-foot national opera building.

It would be topped off with a huge square floating canopy

over 300 feet long

that would protect the complex from the fierce Greek sun,

and generate electricity to run it

from 5,700 solar panels.

Many of the building techniques needed

had never been used in Greece before.

Elly: There were certainly many challenges during construction,

because we were pushing these boundaries in engineering.

The canopy was certainly a very challenging element,

the hill in the park.

The seismic isolation of such a large building...

All of these challenges were overcome

and led to great innovation.

Narrator: One of the most important challenges

was going to be protecting it from the earth itself.

[Alarms beeping]

Ellie: Greece lies on several fault lines

and has a long history of earthquakes.

Traditionally, though, Athens has remained unscathed.

Unfortunately, that changed in 1999

when an earthquake hit and killed 143 people.

Narrator: In 2018,

Greece was hit by nearly 300 earthquakes.

Quakes greater than 6.3 on the Richter scale

can destroy a building.

Ellie: If you're creating any new building in Athens,

you've got to take earthquake risk seriously.

Narrator: Structural engineer Gregory penelis

was part of the team that took on the challenge.

Gregory: Greece has actually 50% of the seismicity in Europe.

So it's obviously a very seismically prone area.

Such a complex structure was obviously a challenge,

not only because of its complexity,

but also because of its criticality,

considering that it is an opera

that has thousands of people inside

when in operation.

So seismic safety was a very big issue

for the design of this building.

Narrator: With millions of people

expected to visit each year,

they couldn't take any chances.

Joshua: The purpose of any structure

is to carry load or forces from where they are

down into the ground,

and that's true of anything...

Buildings, Bridges, chairs, my skeleton.

But when you have an earthquake, what's happening is

that the ground is shaking violently from side to side,

and it's that sideways force

that has to be carried down into the foundations.

So if a structure is in an earthquake zone,

then it has to have a way to resist that sideways motion,

or it will fall down.

Narrator: Most buildings are made to resist force

from the top down.

But with an earthquake,

you get sideways or lateral movement

that can easily destroy most structures.

Gregory: Both the opera and the library

are actually seismically isolated.

Seismic isolation is like you put the building on rollers.

So when the earth moves... Because the earth moves,

not the building...

It moves underneath, and the building stays the same.

A very easy analogy for the non-engineers

is when you have a wooden table and on top of it a toy truck,

and you move the table,

and the truck stays without movement.

The table moves.

Or when you take the tablecloth under the plate,

and the plates stay,

if you can do that.

Narrator: All well and good in principle,

but how do you pull it off with two huge buildings?

Gregory: Here we're in the basement of the opera.

We are at minus 2 meters from the sea level,

from the ground floor.

Every column of the opera and the library

has a seismic isolator underneath it,

and underneath this seismic isolator

there is a concrete pedestal,

and then we are standing on the foundation of the building.

So, the whole building

is seismically isolated from the ground

so that when the ground moves due to earthquake,

the building remains stable.

So when the earthquake happens,

the pedestal and the ground moves with a tolerance

of 35 centimetres, back and forth each way.

One of them is actually the largest one

ever installed in Europe.

The critical thing is how we design

all the mechanical and electrical

and architectural features of the building

that connect the ground to the upper stories

so that they can follow this 35-centimeter movement.

Ellie: Allowing a building of this size

to have 70 centimetres of movement

requires an awful lot of forward planning.

Every wire, every pipe

that's going in and out of this building

requires an extra flexible section

in order that they don't break when the building is moving.

Corina: Every wall joint and every staircase

has to have a movement gap,

which they then fill with silicon filler.

When the building shakes, the silicon breaks.

That's a lot of filling and repair work,

but its much better than the alternative.

Narrator: Their next challenge

was to create the enormous 100-foot-high hill

that gives the building its signature shape.

Hayley: This isn't just about creating a building.

When you're making a whole new hill

you're creating geography.

They've actually altered the skyline of Athens.

Narrator: This 10-million-cubic-foot hill

is made up of enough dirt

to fill 120 olympic-size swimming pools.

3,500 gravel pillars had to be constructed underneath

to hold the soil in place and prevent landslides.

Then, the top was planted with over 1,000 trees.

The effect of creating the park

was to lower the local temperature

from the shade the trees generate.

The hill, though, had another purpose, too.

Giorgio: It was just to give back to this part of the city

the idea that they have the sea very close,

they can use this area

to get to a point where the sea is visible again.

Narrator: At the summit,

looking over the mediterranean sea,

sits the engineers' greatest achievement...

The canopy,

a huge technological marvel

that needed engineering solutions

used nowhere else in the world.

Gregory: It is a structure

that's 100 meters by 100 meters in plan.

The magnitude of this

and the need to create this very large structural spot

of more than 75 meters clear span

led to a lot of innovations.

Hayley: There are 750 panels,

creating a 100-meter by 100-meter canopy

that simply floats on the Athens skyline.

It's a beautiful piece of engineering.

Narrator: As well as being beautiful,

the huge 4,700-ton canopy

had to survive the mediterranean storms

that hit Greece every year.

With wind speeds reaching over 60 miles an hour,

the canopy had the potential to act like a giant wing

and be ripped off the building.

The engineers had to come up with a solution.

They decided to make the roof

so it behaves like a spoiler on a car,

creating down-force when it's caught by the wind.

So instead of lifting,

it pushes down onto the supporting pillars.

To test it out, they built a model

to see how the wind would affect the roof.

Its aerodynamic shape could survive the powerful storms.

They then had to find a material that was strong enough

to span the huge distance and cope with the force of the wind.

They chose ferrocement.

Gregory: Ferrocement has been used extensively

in boat building.

So tankers were built from ferrocement in the '70s,

and also it was used as cladding material

for very elaborate buildings.

Hayley: Ferrocement is made of a fine wire mesh

with a thin layer of concrete.

It was first invented in the 1840s in France

and is thought to be the first ever reinforced concrete.

Ellie: Ferrocement confounds our expectations

about what concrete can be used for.

This is concrete that is thin and delicate and light.

Narrator: Ferrocement can be made much thinner

and outperform traditional reinforced concrete.

But that requires the exact right combination

of cement and reinforcement.

Gregory: We needed to go through very extensive testing

for the ferrocement.

Narrator: When tested, the 2-inch-thick panels

were able to support

nearly 1,000 tons of force per square foot...

The weight of six blue whales.

Gregory: This thin mesh of 1 millimetre diameter

is not produced normally as a structural material.

It's produced as a fence.

Narrator: The ferrocement was thin enough

to keep down the weight of the structure

and strong enough to span over 300 feet in each direction.

The next problem

was that the down-force of the canopy in high winds

would be enough to push the supporting columns

through the roof underneath.

The engineers came up with a radical solution...

To build the canopy its own suspension system.

Gregory: Above us and below us is ferrocement.

Now we can see it,

the whole structure with the ribs,

and we are seeing the suspension system

of the canopy from the column.

Narrator: Instead of sitting on the columns,

the canopy sits on the suspension system,

which absorbs down-force even in heavy storms.

Gregory: The columns enter the canopy,

and then it is suspended with a system of Springs and dampers

from the column,

so it's hanging from the column.

Additionally we have vertical brakes

that don't allow the canopy to move for small winds.

It only moves for large winds.

The whole canopy has an ability to move 15 to 20 centimetres.

But this movement will only happen in a hurricane.

Once or twice per year,

this is the actual frequency

that we have vibrations of the canopy.

To have the actual vertical load

100% of it being suspended from Springs,

to my knowledge, it's the first application in the world.

Narrator: The canopy isn't only for decoration;

its 5,700 solar panels

generate over 2 gigawatts of electricity a year...

Enough to power 1.4 million houses for an hour

and most of what the entire complex needs.

Joshua: This building is designed

to be sleek and stylish,

full of tech, really heavily engineered.

This is a fantastic piece of engineering.

Narrator: The snfcc took four years to build,

opening its doors to the public in 2016.

The building is not only a testament

to how modern engineering can realize the impossible,

but built at a time of crisis in Greece,

it gave hope to Athens

and a modern focus to the city's history and heritage.

Hayley: The snfcc is for everybody,

and it's a real gift to Athens.

Gregory: This building has completely transformed

the whole area of Athens.

It has become a point of attraction for all athenians...

Not only athenians, but all Greeks.

Elly: I think this is one of the most important things,

if not the most important thing,

that has happened in Greece the last few years.

And I'm very proud that I was part of it

and very fortunate.

Narrator: Named one of the world's most beautiful cities,

modern Singapore certainly has some incredible buildings.

But it also has some of the cleverest...

like the hive,

built for the nanyang technical university.

Corina: University buildings haven't really changed

since the 16th century.

Boxy buildings, teacher in the front,

children sitting quietly.

Narrator: It not only looks eye-popping,

but has a revolutionary design...

Classrooms with no corners,

and a building that gets wider as it gets taller

to create an eco-cooling system

capable of combatting the hot and humid Singapore climate,

creating a building for the 21st century and beyond.

Kam chan hin wanted a building custom-made

to teach the next generation of students.

Kam chan hin: This building is very much designed

for the millennials.

The new generation of learners,

they like to explore, they like to participate,

and they go for quick images.

The mobile phone is a good example.

We felt that a building of this kind

actually encourages students to speak up,

to challenge assumptions,

to talk to one another, and to learn from one another.

Narrator: Architect Matt cash

was ready to take on the challenge.

Matt cash: No corners.

No corners. Okay.

Why no corners?

And the idea being

is that in a way, corners are defendable,

kind of you can get your back to a corner

and you're kind of like this,

and it sets up a kind of a dynamic in the classroom

between again the kind of the lecturer or the master

and the pupils,

and they didn't want to do that.

They wanted it in the round.

And it's if you meet at a round table

there's no hierarchy there.

A round table is completely Democratic.

Narrator: The innovations didn't stop there,

because the university also wanted the hive

to be one of the most ecologically friendly buildings

in the city.

Chan hin: We have an overall target

to reduce energy consumption by 30%.

Narrator: The only way to do that

was to get rid of traditional air conditioning.

Matt: When we're thinking about the geometry of the building,

we're thinking about how do you cool that environment

in the best way possible,

not using too much energy?

Ellie: With a single room, we can air-condition it.

When we get to the scale of big buildings, though,

it starts to get expensive

and is a massive drain on energy and resources.

It's not eco,

and we don't like it.

Narrator: So the hive came with two monumental challenges...

To engineer a building without a corner in sight

and to keep it cool

in one of the most humid cities in the world

without air conditioning.

Matt and the team got to work,

reinventing how a university works.

Matt: So we started with one classroom,

which is in effect a kind of an oval shape.

And then we took that one classroom

and we arrayed it,

we clustered it around a central atrium.

And in a way that clustering created the coming together.

So each of the classrooms arrayed around a central space

and then they stagger up and climb.

It's about, in a way, increasing student interactivity.

That was really the beginning of the idea

and the beginning of the form.

Narrator: The hive is made up of 12 8-story-high towers

that slowly creep outwards from the base of the building.

Incorporating these circular classrooms

had drastically changed the shape of the structure.

Corina: You've got a building that's getting wider and wider

before it goes in again.

It's much like a barrel that wants to fall outward.

Narrator: Building towers that get wider was far from easy.

Joshua: Whenever you haveúanything leaning or at an angle,

@then it wants to move sideways,

and there's that sideways force that also has to be resisted

and carried on down to the ground.

The consequences of not considering

the stability correctly at all stages

can be quite severe.

Narrator: The engineers tilted the columns

to work with the unusual shape of the building,

letting them carry the weight of the floors above

straight down to the ground below

in one continuous motion.

Matt: The building kind of progressively steps out.

So each floor

is slightly cantilevered out from the next one.

Now, when you're doing that

with two kind of curving columns like that,

the building wants to fall over.

As the levels step up,

at every level we have a ring beam,

which is almost like in a barrel

where you have horizontal things that ties the barrel together.

It stops the columns falling out,

and that ties the whole structure together.

Ellie: You don't often see leaning columns like that.

It kind of goes against

everything we think engineering should be...

Straight up and down, solid, robust.

Narrator: They may have overcome getting rid of the corners.

Now they had to work out how to keep it cool.

Matt: Part of our challenge, really,

was about the environment in Singapore.

It's a very hot, humid environment.

How do you cool that environment?

And one way of doing that

is to create an atrium in the middle,

and atriums work by hot air,

which hot air rises, rising up the middle,

and then that drags air with it

and creates almost like a chimney.

And that chimney draws all the hot air

up and away from the building.

So the geometry was generated

by trying to kind of cool the middle.

Joshua: This is a form of passive cooling

which uses the form of the building

to block, sink, and dissipate heat

in a natural way,

and it's a great way of really reducing the energy consumption,

which is really important

in somewhere hot and humid like Singapore.

Narrator: The shape of the building

draws hot air up and out of the roof.

The constant flow of air cools it.

And the hive's plants provide added shade,

protecting the building from the sun.

Hayley: The plants inside the building

help to lower the temperature in the hall.

Chan hin: This building is totally energy efficient.

It's been given the platinum Mark for excellence

in energy sustainability.

Narrator: Matt had met the challenges

set by the university,

but he didn't stop there.

He wanted a building that stood out.

Matt: We didn't have enough money

to have a lot of different finishes,

and so in effect the floor, the walls,

the cladding of the outside of the building is all concrete.

People are expecting concrete to be grey,

'cause that's the cheapest way of doing it.

And if you had just a big grey building,

it wouldn't have the kind of textural relief

that you would you would want.

And so we experimented

with lots of different ways of playing with concrete,

treating it in a way like wet Clay.

On the cladding of the building

we use something called a retarder,

which is in effect

something that prevents the concrete drying

at the same speed.

And if the concrete is drying at different speeds,

then some of it's hard and some of it's still wet.

And then you wash that off.

So some of the concrete exposes the stone,

the aggregate inside the concrete,

and some the top surface just the concrete finish.

Having that variety

means your eye kind of enjoys exploring it,

and I think rather than

understanding the building immediately,

it kind of demands you look at it closer.

Narrator: Although it's a radical design,

the building has already won the hearts of the community.

Chan hin: It's called the dim sum building

by some locals.

That is because the shape also resembles the tiffin trays

that are used to serve the dim sum.

Joshua: This is obviously a really beautiful structure.

It would be a great and interesting place to work.

Chan hin: From what we know,

the students actually love the place,

of course it's very iconic.

It's become a bit of a tourist spot.

We're very proud of it.

Narrator: The hive created an environment

that challenged the ideaúof how a university should work

and succeeded beyond all expectations,

showing how engineering

isn't only about keeping a building standing;

it's about changing what's possible.