An event powered by
Close this search box.

How many 2×2 Lego bricks should you stack to break the first one?

A brick can withstand a maximum force of about 432 kg.  To reach the breaking load it would take approximately 375,000, a pile 3.5 km high


It’s not just children who like to build towers with Lego: how many Lego bricks, stacked one on top of the other, it would take to destroy the bottom brick? So, what’s the answer?

The burning debate keeps coming back on social news website Reddit.

It’s a trivial question you might think, but one the Open University’s engineering department has – at the request of the BBC’s ‘More or Less’ programme – fired up its labs to try to answer.

The experiment

The average maximum force the bricks can stand is 4,240N. That’s equivalent to a mass of 432kg (950lbs). If you divide that by the mass of a single brick, which is 1.152g, then you get the grand total of bricks a single piece of Lego could support: 375,000.

So, 375,000 bricks towering 3.5km (2.17 miles) high is what it would take to break a Lego brick.

“That’s taller than the highest mountain in Spain. It’s significantly higher than Mount Olympus [tallest mountain in Greece], and it’s the typical height at which people ski in the Alps,” Ian Johnston says (though many skiers also ski at lower altitudes).

“So if the Greek gods wanted to build a new temple on Mount Olympus, and Mount Olympus wasn’t available, they could just – but no more – do it with Lego bricks. As long as they don’t jump up and down too much.”

credits: Dinu J Nair via Unsplash

The tallest Lego tower… in theory

courtesy: BBC

But could a 3.5km Lego tower really be built?

“There isn’t a chance you could do it in reality,” Johnston says. “Long before the brick fails, the tower would fail as a structure itself, by buckling. The other thing you have to remember is that we were very careful to load this equally down the middle, so that all four walls were loaded.”

A 3.5km tower would have to be built so straight that it was no more than 2mm off centre at the midway point, he says. “And I’d be delighted to meet a Lego builder who could make a 3.5km tower so accurately.”

View of construction of a 36-meter high lego tower, intending to break the Guinness World Record. December 27, 2017 I Credits: Miriam Alster/FLASH90

Certified Lego Builders are a thing

Duncan Titmarsh is the UK’s only certified Lego builder – and one of only 13 worldwide (at least they were in 2012, when this test was run) – and Ed Diment, his partner at company Bright Bricks built the 12.2m (40ft) Lego Christmas tree that stood in London’s St Pancras station on Christmas 2012 , and the 5m x 3m advent calendar standing in Covent Garden.

However, they couldn’t take the challenge. “If you try stacking 2×2 bricks as soon as you get beyond 3 or 4m tall there’s almost no way you can take out all of the kinks,” Ed Diment says. “So it would be totally structurally impossible to do it, whilst it’s an interesting theory.”

And you, are you considering Lego-building something impressive yourself? Let us know: the Call for Makers is now open and we would love to consider your project for exhibiting at Maker Faire Rome 2022 in October!

source: BBC / NYTimes

cover image: Unsplash