BOULDER - The Brewers Association announced on Friday its plans to purchase the building at 1327 Spruce St. in downtown Boulder for $4 million and move its headquarters there next year.

The Brewers Association, the nonprofit trade association dedicated to the booming American craft-beer industry, has leased space at 736 Pearl St. for nearly three decades.

The 11,600-square-foot building on Spruce Street will give the association almost double the space it has now.

"We love 736 Pearl, and we love West Pearl," said Bob Pease, the association's  chief operating officer. "But for many of our workers, they're piled on top of each other."

The U.S. craft-beer industry reported $10.2 billion in retail sales in 2012, up from $8.7 billion in 2011. Pease said the association has 42 full-time and two part-time employees in Boulder, and has been adding one to three per year for the past four or five years.

"I think we are a mirror and function of what is going on in craft brewing and home brewing," Pease said. "And they are both growing at a very healthy rate."

The association has the building under contract and expects to close on the purchase April 1. Pease said the anticipated move-in date is May 1.

An undisclosed local investor, under the entity 1327 Spruce St. LLC, purchased the building in March for $3 million. The building was vacant at the time and remains so.

Pease said Boulder-based Rodwin Architecture Inc. has been hired to redesign and "BA-ify" the three-story building.