Example to Determine Weight of Concrete Slab Per Square Foot (Flat Slab)

• T = Thickness of slab in inches
• L.L. = “Live Load” (Placing of concrete, men & equipment) Use 40 lbs. per square foot (lb./ft.2)
• Wt. FM = Weight of forms Use 10 lbs. per square foot (lbs./ft.2)
• L.L. & Wt. FM. = Use 50 lbs. per square foot (lb./ft.2)
• Wt. Concrete = Weight of Concrete Use 150 lbs. per cubic foot (lb./ft.2)
• T/12 x Wt. Concrete + Wt. FM. = Weight per square foot of concrete slab

EXAMPLE 9″ SLAB WEIGHTS:

• 9/12 x 150 lbs. = 112.5 lbs. per square foot (lb./ft.2)
• Plus 50 lbs. L.L. & Wt. FM. = Total Weight of 9″ slab
• 112.5 + 50 = 162.5 lbs. per square foot’ for 9″ slab= 162.5 lbs./ft.2