Ask Kishore Varanasi how much energy his team’s redesign of the Government Center Garage will save and he’s not shy about giving a highly specific answer.

“It’s [equivalent to] about four million gallons of oil that we’re saving,” said the CBT Architects’ principal and director of urban design in a recent interview.

That’s a result of forward-thinking innovation in the project’s design. CBT plans to reuse half of the existing 2,300-space parking structure at One Congress St. in Downtown Boston, where HYM Investment Group is undertaking a near-Herculean labor to recreate the area around the hulking concrete garage.

The real estate investment group, headquartered in office space at the garage, will build six new structures at the site, with an office tower reaching more than 520 feet and a residential skyscraper standing at 480 feet. To many observers of commercial development in Boston, merely getting that mega-project approved is itself a feat fit for the gods. But it’s not merely the planning that’s impressive; the engineering will also be a serious accomplishment.

CBT’s Varanasi has decided to sit one of those residential towers atop the salvaged garage, which makes sense because a concrete core is the most efficient for that type of structure, he said. His team needs to thread the needle by maneuvering and pouring that concrete core through space in the garage’s frame. However you slice it, it’s a challenging job. But the development team is eying a Leadership in Energy and Environmental Design (LEED) Gold rating for the office buildings and Silver rating for the residential buildings, and the energy savings from reusing the structure is a big gain in attaining those ratings.

“It’s like a puzzle with the sizes of the buildings and all the uses requiring different floor plates,” Varanasi told Banker & Tradesman. “Making them more narrow allows us to move them around.”

So slenderize them he did. Normally in Boston, floor plates in residential towers are 18,000 to 20,000 square feet. At Government Center, however, Varanasi dropped those to between 10,000 and 12,000 square feet. His innovative approach to the towers allowed greater density at the site.

“You can get more floors, and height is value,” he said. “But the question here is: can you permit the height? The logic is that something short and fat is not as attractive as a taller tower.”

Retail Modules

Someday in the near future, greater Boston could be home to what will likely be its first permanent major modular retail store, says Laura Handler, director of service design and strategy at Tocci Building Cos. in Woburn. That cryptic description was as much information as she could give since the project is still confidential.

However, she suspects once other companies see how easy modular retail stores are to build, they’ll follow suit. What retailers need the most in a project timeline is reliability, and modular gives them that, according to Handler. She says Tocci can plan the work so far in advance that they essentially build it virtually and “just drop them into place. Where the real time comes in is how the systems are coordinated between the modules, aligning the ductwork and the connections.”

Using modular techniques, a building can be constructed in two-and-a-half weeks, Handler said.

“The idea is we can meticulously plan out a project so all the needed connections can happen more expeditiously,” she said.

As far as general innovation in the design and construction industry is concerned, Handler said New England is still late to the “sweeping innovation that’s trying to emerge in the design and building industry regarding building information modeling and prefabrication. It always seems that New England and the Boston area aren’t as advanced … and we’re not seeing the level of modeling and prefabrication.”

The Coming Changes

Whatever cutting edge construction ideas are circulating in the industry, projects near the ocean and in flood zones, as are so many of Downtown Boston’s new developments, won’t be worth much if they’re not protected against the potential disasters associated with climate change, says Vivien Li, president of the Boston Harbor Association.

In Everett and Revere, Li is lobbying for the two casino proposals from Steve Winn and Mohegan Sun, respectively, to incorporate increased vegetation and create wetlands along the waterfront that could absorb some water from a storm surge. To date, Mohegan is proposing a parking garage that will not be underground like so many are, and the developers want to achieve a LEED Gold rating.

Winn, on the other hand, is planning large amounts of vegetation and replanting of marsh grasses along the coastline.

“Whatever happens the new buildings will be resilient,” Li opined. “If you’re building a new tower or a casino, you’re going to do what’s right anyway. There is a cost, but because you haven’t started construction yet you can readily adapt your building.”

James Cronin may be reached at jamescroninwrites@gmail.com