ground floor plan el. 'A' second floor el. 'A' basement el. 'A' opt. ground floor w/ service stair el. 'A' (el. 'B' similar) opt. basement w/ service stair el. 'A' (el. 'B' similar) ground floor plan el. 'B second floor el. 'B' basement el. 'B' opt. ground floor w/ service stair el. 'B' (el. 'A' similar) opt. basement w/ service stair el. 'B' (el. 'A' similar)