CONCRETE PIPE 1-S Manholes The Calgary market area is also unique in its square manhole product offering. Type 1-S manholes are used in the City of Calgary for pipe sizes that exceed that which can be accommodated by the standard 5A (1200 mm dia.) material. Type 1-S manholes are manufactured with wetcast concrete and are available in 5 different sizes (1200, 1500, 1900, 2400, and 2800 mm inside square dimensions). PAGE 26 LAFARGE PIPE eMANUAL