In this informative civil engineering article, you will learn the process to measure the quantities of materials like cement, sand, aggregate and steel in 1000 square feet slab(flat, one way & two way) area.

The calculation method will be as follow :-

Area of slab – 1000 square feet

Thickness of slab – 5 inches

Minimum ratio for M20 grade of concrete

Main bar or bottom bar is arranged on shorter distances of 10 mm

Cross bar or top bar is arranged on longer distances of 8 mm

When more steel bars are used on slab, the strength of concrete is increased.

The volume of concrete or concrete mix quantity will be determine as follow :-

Area x thickness = 1000 x 5/12 (to convert inch to cft) = 416.66 cft

To transform it into cubic meter = 416.66/35.3147 = 11.80 cum (as 1m3 = 35.3147 cft)

But the volume is obtained in wet condition and it should be converted to dry volume by multiplying with 1.54 i.e. 11.80 x 1.54 = 18.17 cum

After summing the ratio, we get 1 + 1.5 + 3 = 5.50

The quantity of cement = 1/5.5 x 18.17 = 3.30 cum x 28.8 (to convert it to bags multiply with 28.8)

How 28.8 is derived :-

In 1m³, the quantity of cement = 1440 kg

In one cement bag, quantity is 50 kg

So, total bags = 1440 / 50 = 95 bags

The quantity of sand will be determined as follow :-

Sand = 1.5 /5.5 x 18.17 = 4.95 cum

To convert it to cft, multiply with 174.80 cft

The quantity of aggregate will be determined as follow :-

3/5.5 x 18.17 = 9.90 cum

To convert it to cft multiply it same as above i.e. 9.90 x 35.3147 = 349.60 cft

The quantity of steel will be determined as follow :-

Steel = 0.5 to 1% of total concrete volume

After taking the average value, we get 0.75 %

Now 0.75/100 x 18.17 (dry volume) x 7850 (In 1m3, the quantity of steel = 7850 kg) = 1070 kg