Construction Junction flew in the face of retail rules when it opened the doors of a cold, dark warehouse under the 62nd Street bridge nine years ago. Even in brighter digs now -- a warehouse in North Point Breeze -- it is cold in winter, the products are grungy and many have missing parts.

But at least the economic news isn't grim: Construction Junction will ring up $1 million in sales for the first time this year.

Simply C.J. to its customers, the nonprofit was one of Pittsburgh's first green businesses, fueled by a $200,000 Heinz Endowments grant. Its mission: To stay afloat in order to keep building materials out of landfills.

Today, it's not just profitable; it is diverting more than 720 tons a year from landfills.

"I wish I could say" what part environmentalism plays in customer interest, said director Mike Gable. "Since the economy went in the tank, reuse organizations have experienced a bump, and we're mirroring the trend, but the numbers are far beyond what I would've expected. We're all a bit flabbergasted."

This past week, the Social Innovation Accelerator -- a support organization for social-enterprise nonprofits -- recognized it as "the best of the best" of its 40 clients in southwest Pennsylvania.

"We are identifying them because they have excelled in all key areas important to social enterprise," said Gerald Driggs, chief executive officer of the Accelerator. "They are generating a surplus that they can put back into the organization, and 98 percent of their annual budget comes from earned income."

Mr. Gable said he remembers "feeling panicked about where stuff was going to come from" when the enterprise started. "I wondered what we should do, drive the truck around on heavy trash days?"

With a presence at the annual home and garden show and some media coverage, word of mouth spread, and contractors, customers and donations of every vintage and condition began trickling in: tubs and sinks, bannisters, brackets, cabinets, flooring, mantels, doors, windows, buckets of hardware, locks and hinges, grinding wheels, gates, lamps, chandeliers, toilets and tank trays, stoves, bed frames, couches, chairs, crown moulding, tile and glass block, even partially used cans of paint.

Owners get a tax deduction in return for their donations. For Jack and Kathy Demos, of Fox Chapel, the tax break was bigger than most -- $27,500. Then again, their donation was bigger than most -- just about everything portable from a 50-year-old brick Colonial they tore down this summer to make way for a new house.

They donated all the doors and windows, mirrors, tubs and shower units, garage doors, granite counter tops, kitchen cabinets, chandelier and lighting fixtures, air-conditioning and all appliances. The crew even took door molding, part of a fence and the concrete pavers from the driveway.

"I was amazed at what they could utilize," Mr. Demos said. "We wanted to put as little material in a dump as possible. Hopefully, someone else could use it."

Another piece of Fox Chapel was on display near Construction Junction's checkout counter recently. A huge white-painted Colonial-style doorway with leaded-glass sidelights and transom came from an 1870s estate and was priced at $1,100.

Looming above it was a Classical stamped-tin pediment from a century-old commercial building on Fifth Avenue, Uptown. Now priced at $3,000, it once hung 45 feet above the busway. It took a salvage crew three days to remove, said Brian Swearingen, the nonprofit's deconstruction field manager.

Tony Williams, property manager of Sal Williams Real Estate, donated the pediment along with a 20-foot-high cast-iron staircase and some tin ceiling panels. The company, which owns about 150 properties Uptown, tries to rehab when possible, he said.

"If it looks good from the outside, we try to save it, believe me."

This building had a cracked foundation and was dangerous, he said, but had architectural elements that were worth saving.

"You recycle when you can. I hate to see that stuff go to waste."

In 1998, three tons of vinyl siding got the whole thing started. Lou Tamler, then regional director of the Pennsylvania Resources Council, fielded a call from a man who wanted guidance on getting rid of the siding. The only option -- the landfill -- was an untenable option to the Council, the Green Building Alliance and Conservation Consultants -- all tenants of Pittsburgh's EcoCenter on the South Side. Together, they conceived Construction Junction.

Walt Banker, of O'Hara, has shopped there since the under-the-bridge days. He said he is "kind of both," home owner and contractor, "when you have five children and you're always renovating your house."

The store has saved him in more ways than one, he said. "There's stuff you need you can't find anywhere else, stuff that isn't even on the market anymore."

New materials sell for about half the cost charged at a conventional retailer, and older items are priced according to degradation or antique value.

"I go about once a week, and I let them know if I'm looking for something," said Mr. Banker. "Lately I've noticed they have a lot more stuff because they're getting more popular."

For all its success, the nonprofit hit a rough patch in 2006. A seat-of-the-pants operation lacking in tech savvy, it had no inventory value on its balance sheet, no inventory or customer data management and no edge. "We had begun to lose a little fire," said Mr. Gable. "We had bigger losses than usual and we were not as aggressive at getting things into the building."

Running a deficit into 2007, the board asked the Accelerator for help.

The Accelerator gets its support from foundations. It has plowed $200,000 in direct funds and staff support to account for and combine the inventory and donor networks. The investment also sophisticated C.J.'s outreach with an interactive Web site. More than 6,000 e-mail blasts go out each week pitching new salvage and donations and to solicit feedback.

The board established an annual fundraiser last year that grossed $60,000. The "Steel City Big Pour," a beer-tasting party at the warehouse, grossed $91,000 this year, of which about $55,000 benefited C.J.

The staff has grown from Mr. Gable alone to 18 people. Five partner tenants, most with environmental missions, help generate income. The Pillow Project, a dance company, lives free on the second floor and manages events that benefit C.J.; Free Ride, a project of Bike Pittsburgh, repairs donated bikes, donates bikes to Third World countries and holds repair workshops.

C.J. also leases space to Reclamere and eLoop, two electronics recyclers, and gets a percentage of the fees customers pay to have their cast-offs recycled responsibly.

The city of Pittsburgh also has a recycling drop-off station on the site.

Steel City Biofuels, a nonprofit that promotes use of biofuels in vehicles, took up residence in the warehouse last year and is expecting a state grant to install a biofuels pump at C.J.

"One reason we're excited to be part of this is that there is such a compelling vision," said Nathaniel Doyno, director of Steel City Biofuels. A $300,000 grant from the Heinz Endowments is pending to make the warehouse "a net zero energy building, to take it off the grid," said Mr. Doyno. His enterprise will manage the alternate fuel co-generation system, "a bio-mass-powered operation that combines urban wood waste, organics from local restaurants and biofuels that include vegetable oil."

Ultimately, Mr. Gable said, he would like Construction Junction to anchor "a green mall, where people can exercise green consumer choices in one place. We're now uniquely positioned, and I'm excited about the future."