How to estimate the quantities of bricks, cement, sand,etc in Brickwork, Mortar, Plastering.???

Bricks, Mortar:- Sand and OPC for class2 mortar

            For half brick wall(4.5 inch thick)

               No. of Bricks:- 55-60 per sq.m.

              Sand:- 54.5kg or 0.04 cu.m. per sq.m.

              Cement:- 15.5kg or 0.01 cu.m. per sq.m.

     And for one brick wall(9 inch thick)

              (just double above)

      In general, also 2.5% breakage should be added & 20% wastage on mortar.

Plaster:- (12mm thick plastering)

           Sand:- 14kg , Cement:- 4kg   per sq.m. of wall

    Also 15% wastage with a brush plaster finish for 

       interior walling.