It helps that the Rockville company recently became the sole Washington, D.C.-Baltimore area distributor for Hanson Brick. Hanson, of Charlotte, N.C., has annual sales of $370 million and manufactures more than 1.6 billion bricks each year.

The alliance with Hanson is expected to pay dividends within the next two years, increasing Potomac's brick sales by as much as 8 million units, said Alan Richardson, Potomac president and CEO. The company now distributes more than 70 million bricks annually.

"We've been selling Hanson's products for years, along with several other distributors in this area," he said. "But now we're the lone one."

Simon Bates, commercial president for Hanson Brick, said his company expects to see its volume grow nicely in the Washington-Baltimore area through this partnership.

"Potomac Valley Brick has a strong presence in Maryland and is now expanding into northern Virginia and Delaware. We are excited to be part of that expansion," Bates said. "We want to partner with companies with similar cultures and work together to develop mutually beneficial business plans."

Potomac is on track to reach $46 million in sales this fiscal year, which ends Sept. 30, Richardson said. That would be a nice jump from last year's $42 million, although not all of that projected increase can be attributed to the Hanson brick line.

"Our goal is actually $50 million this year, but we had a slow January. We had a good February, and March is looking better," Richardson said. "We've sold an increasing amount of accessories."

With that sales jump, Potomac has hired four new employees since January. Three more should be added by the end of the year to boost the company's employment to 67, Richardson said.

Across the country, the number of new single-family homes built using brick as its exterior increased about 30 percent between 1992 and 2002, from 200,000 to 261,000, according to Census Bureau figures. But vinyl siding use really snowballed during that span - from 222,000 to 525,000 - comprising 40 percent of the total industry share in 2002, compared to 20 percent for brick.

Most of the production of brick homes is in the southern United States. The New England and Middle Atlantic states account for only about 6 percent of new brick homes in the country, according to the Brick Industry Association of Reston, Va.

A fair number of local homes feature brick fronts and siding on the other sides, said Michael Carliner, an economist with the National Association of Home Builders of Washington, D.C.

"Vinyl has not really replaced brick. It's replacing aluminum and wood more," Carliner said. "The brick share is more stable."

Jim Kneussl, board president of the Greater Capital Area Association of Realtors, said he hasn't noticed a local trend toward building with brick more in recent years.

"It depends on where the buyer comes from," Kneussl said. "If you're used to vinyl siding, you tend to go with vinyl siding. If you're used to brick, you tend to go with brick."

Tradition and costs are among the reasons that many local homebuyers go with siding over brick, Richardson said. "But I'm working to change that," he said, noting advantages to brick such as greater durability and energy efficiency.

Richardson and his father, the late Jack Richardson, were among four co-founders of Potomac Valley Brick in 1976. Richardson has since bought out the other two former partners and opened additional offices in Baltimore and Newington, Va. He hopes to move his headquarters to a larger 12,000-square-foot space about a mile from his present Rockville office by this summer.

The company has sold brick for many notable projects, including the University of Maryland's north entrance walls and St. Mary's College student townhouses. Potomac even donated brick to restore the kitchen of the historic Decatur House, one of the oldest surviving homes in Washington, D.C., which dates to 1818.

"We want to do more of that kind of community project," Richardson said.