Principality Stadium: A roof debate lasting 20 years

The Principality Stadium is turning 20 years old - and for all those years there has been only one question on everyone's lips.

It rivals the great debates of jam or cream first? Were Ross and Rachel on a break? Biscuit or cake?

Well Wales has a much better one. The roof. Should it be open or closed?

It has been the subject of many disagreements, often in the rugby world, but also when music gigs take place at the stadium.

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Rugby fans will remember in March when Wales boss Warren Gatland said: "It's our stadium and we should be able to do what we want with it," after Ireland requested the roof be open for their match. Both teams have to agree to a closure.

Eddie Jones, England's coach, said he cannot understand why the use of the roof - open or closed - is an issue.

Open or closed?

"I don't care. It makes no difference because both teams have to play under it," he said at the time.

England opted to have the roof open during their Six Nations match against Wales in 2017, but left it late to decide. They went on to win 16-21.

'Damned if you do, damned if you don't'

Paul Sergeant, who was the stadium's chief executive between 2003 and 2006 - when it was called the Millennium Stadium - said he did not think the players are bothered too much about the roof.

"When you talk to players about the noise, they say they don't notice it, they're so engrossed in the task at hand, I don't think it matters to them," he added.

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So what about the big question everyone wants to know - who makes the decision about whether the roof should be opened or not for an event?

"Back in the day we as operators of the stadium had the say," Mr Sergeant said.

"It was down to a number of factors, most importantly around the weather.

The roof was closed when Wales beat England in 2013 to secure the Six Nations win

"We had to protect the field and the spectators, but you're damned if you do and damned if you don't. People will complain like hell.

"The weather forecast is only right half the time, you're stuck in no man's land."

But Welsh mezzo-soprano singer Katherine Jenkins, who has performed the national anthem at rugby internationals, has said she prefers the roof closed.

"I was always really excited when I knew I was singing the anthem at a match when the roof was going to be closed because it just amplified everything," she said.

"All of the emotion, all of the singing, all the cheering was just even louder so I really loved that."

Paul Sergeant was the stadium's chief executive between 2003 and 2006

The stadium hosted the FA Cup final for six years between 2001 and 2006 while the new Wembley Stadium was under construction.

It was during those six years that the roof almost failed the team. In 2003 Arsenal played Southampton and Mr Sergeant said they made the decision to close the roof due to the "lousy weather", but instead of taking the usual 20 minutes to open, after four-and-a-half hours, it still was not closing.

"It broke down on us, we eventually got there but it was a tad embarrassing and stressful, but we got the job done."

Music fans have also struggled as the roof was left open for the Spice Girls gig, leading to some social media complaints about not being able to hear as well. Oh and the weather...

And when Pink recently took to the stage, questions were asked then if the roof would be open or closed. It was closed - much to the delight of her fans who saw her suspended overhead from the roof, "flying" over their heads as she belted out her hits.

"If it's open, the rain doesn't fall straight it can blow at the lower tiers," Mr Sergeant said.

"You couldn't open or close mid-way through, people get pretty nervous when metal is moving above their head, you could do some serious damage."

Pink performed some of her concert suspended from the ceiling of the stadium

The roof is subject to extensive checks and costs £2.54 to open each time, bargain!

"Occasionally if there's pyros, you'd crack it open a metre to let the smoke out, but that'd be it."

As for the opening of the roof itself, it is simply "a series of buttons in a control room" which a handful of people have access to," Mr Sergeant said.

The all-seater stadium has the capacity for 73,931 people and its is only the second stadium of its type in Europe.

Cardiff had held the number one spot for the biggest stadium with a retractable roof in the world, until the AT&T Stadium, formerly Cowboys Stadium, in Texas took the crown.