How to Calculate Number of blocks or Hollow blocks Quantities in block wall ?

Hollow Block :- is a concrete block used in construction to build an internal & External Walls , there are different size of hollow blocks are used in construction, Hollow Concrete blocks are made of Portland cement, fine aggregate and sand. Usually fly ash or bottom ash is mixed with the concrete mixture.

How to calculate Hollow Block Quantities in Wall

For Example Wall Size is

Length (L) -1m, Height (H) – 1m and Width (W) is-1m  

Standard block Size –400 x 200 x 200 mm / 0.40 x 0.20 x 0.20 m (Without Mortar)

Mortar Thickness is -10mm, 10mm mortar used in all the four sides

Block Size with Mortar – 410 x 210 x 210 mm / 0.41x 0.21x 0.21 m

Formula to Find the Number of Block Quantity in Wall is

Formula = Volume of Wall / Volume of One Block

Volume of Wall   = Length (L) x Width (W) x Height (H)

Volume of Wall   =  1 x 1 x 1 = 1.0 mᶟ

Volume of one Block without Mortar = 0.40 x 0.20 x 0.20 = 0.0160 mᶟ

Volume of one Block with Mortar       = 0.41x 0.21x 0.21 = 0.0181 mᶟ

So, No of Block Required in 1mᶟ of Wall is

No of Block without Mortar  =    1.0 / 0.0160 = 62.50 /say 63 No’s

No of Block with Mortar        =    1.0 / 0.0181 = 55.31 /say 56 No’s

Usually Wastages considers 5% in block Work

No of Block with Mortar        =     (1.0 / 0.0181)+5% of Total No’s of Blocks

No of Block with Mortar        =     (56)+(56*5%) = 59 No’s of Blocks Requires

1. Block Without Mortar (400 x 200 x 200) mm Size  Required in 1mᶟ = 63 Nos

2. Block With Mortar (410 x 210 x 210 ) mm Size  Required in 1mᶟ = 56 Nos  (Without wastage)

3. Block With Mortar (410 x 210 x 210) mm Size Required in 1mᶟ = 59 Nos (With wastage 5%)