PURPOSE: To efficiently obtain reinforced building sheets, by successively placing a web and plastic mesh on a conveyor belt, further supplying a cement mixture contg. Portland cement, inert materials, fluidizing materials, water, etc., thereto and subjecting the mixture to smoothing and compressing.

CONSTITUTION: The continuous supporting web 8 is supplied onto the impermeable conveyor belt 2 progressing horizontally at a specified speed and further, the plastic mesh 9 is supplied thereon. The cement mixture 10 contg. 50 to 85% Portland cement, 10 to 50 wt.% inert materials (e.g.; sand), 0 to 15 wt.% additives (e.g.; coloring agents), the water of 20 to 32 wt.% of the cement, the fluidizing agents (e.g.; anionic dispersants) of 0.5 to 2 wt.% thereof, etc., is supplied the mesh 9 and is smoothed. The supply of the mesh 9 and the cement mixture 10 is repeated until the prescribed thickness is obtd. and thereafter the mixture is compressed, to produce the building sheet.