Pepper Construction crews build new club lounge spaces beneath the stands at Wrigley Field. (Courtesy Pepper Construction)

The five-year rebuild of Wrigley Field became a tricky process, tied to intricate sequences for scheduling major construction inside a century-old stadium, project officials said.

In addition, the Cubs have made the playoffs the past four seasons, putting additional pressure on Pepper Construction, the team’s general contractor. In 2016, the year the Cubs won the World Series, the builder had a short 20 weeks of offseason to finish construction, which included clearing space behind home plate to build the 7,200-square-foot American Airlines 1914 Club.

“Opening Day doesn’t change, and depending how well the team does in the previous fall, the end of the season can be anywhere from Oct. 1 to Nov. 1,” said Scott Higgins, Pepper Construction’s senior vice president. “Fortunately for the project team, not (advancing) in the playoffs beyond the wild-card game last fall was a blessing in disguise, because it gave us the extra time we really need this winter to accomplish everything they’ve asked us to do.”

Pepper Construction has restored other Chicago landmarks such as the Chicago Art Institute, the Palmer House Hilton hotel and department store Marshall Field’s, which became Macy’s in 2006. Higgins has been involved with Wrigley upgrades since fall 2010, when he took the Cubs’ first phone call. At the time, the Cubs formed a “dream team” of architects and urban planners that included consultant Janet Marie Smith and DAIQ, designer of restorations to Fenway Park and Rose Bowl Stadium. The Cubs eventually handed the project to Populous to design the premium clubs and suite renovations, among other improvements.

The Cubs hired CAA Icon as owner’s representative, a firm headed by Tim Romani. The central Illinois native and lifelong Cub fan got his start developing a new ballpark for the Chicago White Sox, now called Guaranteed Rate Field, that opened in 1991.

Working on Wrigley upgrades project has been a labor of love for Romani.

“We kind of knew what we were getting into,” Romani said. “The challenge was dealing with the physical aging of the building. It’s like if you bought a 100-year-old home and you need to restore it. Every time you open up a wall to do something minor, you find something that turns it into a major thing. We encountered a lot of that along the way that there was no way to foresee.”

A lot of time and money was spent correcting structural deterioration that wasn’t necessarily in the budget to begin with, he said. In many cases, it meant strengthening the foundations before adding more structural load with new construction.

“If you were to look at the structural cross section of the ballpark, you would never build it like that today with support columns that go through the seating bowl,” Higgins said. “With the help of (structural engineer) Thornton Tomasetti, we had to devise a logistics plan with sequences in every zone. Everything had to start from the bottom up. The project has taken longer than they wanted it to, but after the sequencing plan was worked out, it was going to take (five to six years) to do everything.”

Despite the complications, the Cubs made smart decisions at every turn and it has paid off for the historic venue. The sold-out American Airlines 1914 Club is one of the finest premium lounges in sports, said Romani, whose portfolio covers $8 billion in sports construction over his 27-year career.

“They didn’t make it easy for CAA Icon,” he said. “We had to react very quickly and make a lot of changes on the fly, but every one of them was the right thing to do.”