A two-section $27 million building that will have office space and luxury cooperative apartments is under way on a downtown site.

Named Washington Park, the building at the intersection of K, L and 22nd streets NW will include 67 apartment units, some of which will have two stories, in an 11-story building along L Street and office space in an eight-story building at the corner of 22nd and K.

Completion is scheduled next spring for the building that will have separate entrances on 22nd Street for apartment owners and office tenants. Smith, Segreti and Tepper designed the building that is being constructed on a former parking lot operated by Colonial Parking Inc.

Developer David Evans is a partner in the undertaking with Thaddeus Lindner and Sergius Gambal of Colonial Parking and also A. James Clark, a construction executive. Omni Construction has the general contract for the reinforced concrete and steel building that will have a dark brick exterior.

Evans said that part of the site (on KStreet) is zoned for an office building and the other part on L Street for residential construction. He said that the building will have a common wall separating the residential and office sections.

Prices for the large apartments in Washington Park will range from $160 to $200 per square foot of living area, making it one of the most expensive new residential buildings in the area. Evans said that 45 apartments will have two stories of living area. The upper level apartments will have roof gardens and fireplaces. Other units,which will range from one to three bedrooms, will have balconies or terraces.

Evans said the 105,000 square feet of office space is scheduled to be leased in a range from $25 to $30 a square foot. He said apartments will range from 900to 2,200 square feet of living area and be priced up to $400,000.

Philip Mudd of Brooks, Harvey placed permanent financing with Lincoln National Life Insurance Co. American Security Corp. is providing construction financing.

Evans, who head a development firm that recently completed a new office building in Tysons Corner and plans a second there, also is a member of a group that plans to develop a 57-acre tract near a planned Metro station at Nutley Road and Route 66 in Fairfax County.