Montgomery County will have a new civic center -- in the old Silver Spring Armory -- and soon may have a rural conference center at Woodlawn, one of the county's historic Quaker farms, near Sandy Spring.

Bought recently by the Maryland National Capital Park and Planning Commission, the two properties would rank among the largest publicly owned meeting spaces in the county.

The Montgomery Planning Board last week approved a "concept plan" to renovate Woodlawn for a conference center, and asked the public's help in renaming the former National Guard Armory.

The $1.5 million renovation of the three-story brick armory in downtown Silver Spring is almost complete, and tentative bookings for its 10,000 square feet of space already are being made for this fall. A large area formerly used for drill practice will seat more than 450 people.

The planning board is considering renaming the 1927 building, known both as the Silver Spring Armory and National Guard Armory. The building and 1.6 acres, at Fenton Street and Wayne Avenue, were bought from the state in 1974 for $790,000.

The only other large, publicly owned civic center in the county is in Rockville. It is an 18-room, 19th century mansion of 65 acres near the center of the city. Rockville bought it in 1956 and added an auditorium that seats 500.

The park agency bought Woodlawn, its stone barn and 82 acres last year for $550,000, and expects to spend between $125,000 and $160,000 to renovate it and redesign the interior of the large farmhouse to provide meeting space for about 50 people. The barn, now being used as a park police stable, also could be renovated. A park police substation is now housed in one of the farm's outbuildings.

Woodlawn, not connected with George Mason's Woodlawn Plantation south of Mount Vernon, was built by the Quaker Thomas family and occupied by a Quaker doctor, William P. Palmer, and his descendants until the 1920s, according to park historian Michael Dwyer. The park agency plans to employ live-in custodians at both the armory and Woodlawn.