Arena remodeling is a game of inches.

That might be hard to surmise, given that bulldozers, cranes and dump trucks were among the heavy equipment used to renovate the building now known as Allstate Arena.

Allstate Arena Executive Director Harry Pappas points out some of the improvements being done inside the arena as workers prepare for the facility's opening.

But for all the alterations and safety features made to the structure - including wider aisles, larger concourses, additional bathrooms and an updated facade - Harry Pappas believes visitors also will appreciate the small changes, like the few inches being added to the seats.

The arena's executive director points to the lower level. There, hard, plastic seats that measured 17 to 19 inches wide have been replaced with upholstered seats measuring 21 inches wide. Eventually, the entire 19,000-seat arena will have comfy chairs.

"The old seats were good in their day, but this is what the fan expects now," said Pappas, admiring one of the new seats. "It's the little things that count."

There are plenty of big things to notice about the $20 million renovation, which began June 15 and the majority of which will be completed in time for the grand opening of the Allstate Arena.

Visitors first view the changes upon pulling into the parking lot. The dreary facade of the old Rosemont Horizon has been replaced with a polished exterior featuring reflective glass panels, flags and a neon logo. These architectural touches, which cost $4 million alone, are the signature of the new Allstate Arena.

The shape of the stadium is different because 45,000 square feet of space has been added, mainly in the concourses and aisles. Exterior walls were ripped out so that the lobbies could be expanded at each entrance.

Space also was added to improve crowd flow. In the old building, people had to navigate their way through aisles and lobbies with widths as narrow as 5 feet. The new aisles are at least 10 feet wide, while the concourses are at least 60 feet wide at each entrance.

"These changes should add to the convenience of our customers. It will let them get in and out of the building faster," Pappas said.

Inside, the lower level of the arena has been reconfigured to improve sight lines for visitors. While the old floor configuration was square, the new design has an oval shape, improving the view for events, especially basketball and hockey games.

To complete the redesign, the arena's floor had to be removed and concrete poured to create the new curved shape along the base of the lower level.

The reconfiguration would have allowed Pappas to add thousands of new seats, but he decided to increase seating by only 500. The number of skyboxes remains at 48.

"We could have increased capacity quite a bit, but our goal was to increase the comfort level for people without reducing the intimacy of the arena," he said.

At the rear of the lower-level seating, handicap-accessible mezzanines were expanded, not only increasing the square footage, but also improving traffic flow.

The timing was right for improvements, Pappas said. The arena had not undergone a major upgrade since its opening in 1980. A small renovation in 1994 expanded the eastern concourse and improved the ice rink. And with a new name being attached to the building, a renovation added to the sense of a new beginning, he said.

"Let's face it: This building was fine for 1980, but we needed to do some things to keep up with the times," Pappas said.

The Addison-based architectural firm Anthony M. Rossi Ltd. designed the renovations, working from plans it created when designing the original structure. The arena was closed for six weeks so work could be completed.

Changes to the upper levels will follow, but a number of improvements already have been made.

In the old Rosemont Horizon, visitors sitting in the upper levels had to walk downstairs to use the restrooms. The redesign has added eight restrooms to the upper levels. This doubles the total number of restrooms in Allstate Arena, 70 percent of which are for female patrons.

The upper levels also will be fitted with new signs, while work will be done to improve acoustics, Pappas said.

More changes are planned for the upper levels, but Pappas wants to plan carefully.

"We didn't want to bite off more than we could chew, especially since we are booked for acts beginning in early August," Pappas said. "The main goal was to be ready for the opening of the new Allstate Arena."

As customers grow accustomed to the new facility, Pappas believes they will grow to appreciate the changes being made, both inside and out.

"There's no doubt that this building is the most attractive along the I-90 corridor, if not the Chicago area," Pappas said. "Someone called this a new Taj Mahal. I think they're right."