Its 12-inch-thick walls were great for retaining below-zero temperatures in the six-story building. The walls were insulated with cork and cooled by a 77-mile-long network of pipes that circulated chilled saltwater from locomotive size condensers chugging in the basement.

But those walls were a huge obstacle when developer Gary Hassenflu agreed to purchase the 450,000-square-foot building in 2004 with an eye toward converting it into 224 aparments.

Thanks to what is being described as a 'herculean' effort, federal officials have permitted Hassenflu to poke holes, literally, in the usually strict preservation rules that prohibit significant changes to a building's exterior.

He has been allowed to cut 142 large windows into the blank brick walls of the building and still qualify for $9 million in federal and state historic tax credits essential to the project's financing.

By December, the $35 million residential project, the largest in the River Market and one of the largest renovation jobs downtown, is scheduled to open.

The development also is using state affordable housing tax credits and will add 200 units to a downtown market eager for more reasonably priced apartments.

'It's a great idea,' said Stacia L. Johnson, Kansas City housing administrator. 'It's a concept that needs to be copied.'

The project will receive a 25-year property tax abatement from the Planned Industrial Expansion Authority, 100 percent for the first 20 years and 50 percent for five years.

It wasn't easy convincing the U.S. Department of Interior, the guardian of the historic tax credit program, that the windows were the right way to pursue the 'white elephant' project, said Elizabeth Rosin of the consulting firm Historic Preservation Services.

'We played every card we could,' she said. 'We approached the project knowing it would be initially denied, and if we were to be sucessful it would be in the appeal process. It was sort of a herculean task.'

The application process took 10 months. In February 2005, Hassenflu got the green light from Washington.

Hassenflu had limited experience as a developer before tackling the Cold Storage building. The Prairie Village based businessman had done a couple of smaller apartment projects in small towns, but his only historic preservation work had been renovating a former Wichita warehouse into the 48-unit Harvester Lofts.

He approached Blast Inc., the owner of Cold Storage, in April 2004 after that company had considered the possibility of redeveloping the property but decided to pass.

'They saw the amount of work with it and felt it would have a limited return,' he said.

The 45-year-old developer was sitting in a makeshift office in a two-story annex to the main building. He plans to convert the annex into offices for his company, Garrison Development, as part of the project.

Outside, dozens of workers were busy removing debris from the huge building and installing the framework for the apartments. More than 2,200 tons of concrete flooring have been removed to create light wells several floors deep that are illuminated by skylights cut in the roof.

Before workers could even start last September, the old building had to gradually thaw to avoid damaging the structure. The great meltdown began in July, after Blast moved its operations to subterranean storage complex, and the building wasn't completely defrosted until mid-December.

Much of it had been frozen since it opened in 1922 as part of a network of facilities built by the U.S. Cold Storage Co. in Chicago. Besides Kansas City and Chicago, the company operated similar buildings in Detroit and Dallas.

The facility had more than 38 million cubic feet of refrigerated space, almost as much as the entire New York City metropolitan area at the time, according to Rosin. The company also sold up to 100 tons of ice to local customers.

The new project will help new residents cool off by providing a rooftop pool.

Other amenities include a rooftop running track, exercise room, enough indoor parking for 130 cars and an additional 150 parking spaces outside.

The developer also is contemplating a 'green roof' garden that would cover about 7,200 square feet.

The one, two and three bedroom apartments will range from 700 to 1,200 square feet. Ninety percent of the apartments will be set aside for the affordable-housing program with rents ranging from $575 to $775 per month. The market-rate units will rent for $800 to $1,300 per month.

When the windows get installed, the views from the Cold Storage building should be impressive.

The south side of the building had plenty of windows looking out on the downtown skyline. The additional 7 by 14 foot windows being cut into the west, north and east sides of the building will give residents a panorama of the River Market, the Missouri River and beyond.

John Sandor, the Department of the Interior staff person who originally rejected the Cold Storage application, said it was accepted on appeal because the person who reviewed it 'with a fresh eye' believed that the new windows didn't detract from the building's quality.

The agency did require that no windows be created on the east and west corners near the south facade so that the front of the building would continue to appear the way it looked originally.

'A lot of people didn't want to pursue the project because they didn't think they could get the tax credits,' Hassenflu said.

'We argued 'What else could you do with this building without windows?' and the need for more affordable apartments in the market.

'It's been unprecedented, and I have to give a lot of credit to our historic consultant, Elizabeth Rosin.'