Mercedes-Benz Stadium officials are finally ready to show off the building's retractable roof in operation.

The Falcons, who open training camp this week, plan to hold a public roof-opening ceremony before a team practice in the stadium Sunday. Several days earlier, on Wednesday afternoon, media members have been invited to the stadium for a demonstration of the roof opening and closing.

The events mark what stadium officials call the completion of construction on the roof, 11 months after the $1.5 billion-plus venue hosted its first event.

The complicated, eight-piece roof caused construction delays and cost overruns when the stadium was being built and wasn't fully automated when the stadium debuted last August. The roof has been open for only three major events to this point – one Falcons game and two Atlanta United matches – and at least until recently it hadn't operated with the designed speed or efficiency. Compounding the issues, the closed roof leaked during several events, including during warmups for the college football national championship game in January.

Stadium officials are hoping to move on from all of that. They said in March that much progress had been made on the roof, and they started what they called the final phase of roof work in late May. The work is now said to be finished and the roof ready to retract as desired.

The roof is designed to open or close with the push of a single button in about 12 minutes, with its eight pieces giving the optical illusion of rotating as they open, according to the architects. Falcons fans can see on Sunday – the first time the roof will be moved with a crowd in the stadium – if that standard has been met.

The roof is an engineering wonder, to be sure. Each of the eight triangular steel pieces, called petals, measures more than 200 feet long, weighs more than 500 tons and moves in straight lines along separate tracks. The petals rest on bogies, which are mechanisms that sit on the track rails. When the roof is opened or closed, the motorized petals move along the tracks, which are attached to the 18,000-ton fixed portion of the roof.

The petals cantilever over the field when the roof is closed. They are four different sizes because the roof is not a perfect circle. They move independently but in concert.

Going forward, it will be interesting to see how often the roof is open for Falcons and Atlanta United games. The teams’ owner, Arthur Blank, and other officials have said they plan to play more games with the roof open than closed.

That would buck the trend of the four other NFL teams with retractable-roof stadiums. Collectively, the Arizona Cardinals, Dallas Cowboys, Houston Texans and Indianapolis Colts have chosen to play with their roofs open in only about one-third of the games.

The NFL has said it would like to have the option of playing Super Bowl LIII, which will be in Mercedes-Benz Stadium on Feb. 3, with the roof open if the weather is favorable – a big if, of course.

» More: Follow AJC's continuing coverage of Super Bowl 53

Tickets for Sunday’s practice and roof-opening ceremony are $5 per person. The ceremony will begin at noon, weather permitting.

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TODAY’S LEADOFF LINKS 

> The Braves will trade for a reliever, Mark Bradley writes. But do they also need to acquire a starter? See his column here.

> Don't expect Cristiano Ronaldo to be in action for Juventus when it plays the MLS all-stars at Mercedes-Benz Stadium on Aug. 1. See Doug Roberson's story here.

> If Tiger Woods keeps this up, he may be back at East Lake for the Tour Championship, Steve Hummer writes.