# PARAM VISIONS

All about civil construction knowledge- PARAM VISIONS

### Calculating the cost of stone (random rubble) masonry work./Rate analysis of random rubble (stone )masonry work.

Let us consider RR ( stone ) masonry wall for the calculation purpose as shown in the below drawing.

Given data:

Length of the stone masonry wall = 15 ft.

Height of the stone masonry wall = 7 ft.

The thickness of the RR masonry wall = 1.5 ft.

The total volume of the RR masonry wall

= [length × height × thickness]

= [15 ft. × 7 ft. × 1.5 ft.]

= 157.5 cu ft.

Before proceeding further, go through the article ðŸ‘‡

to understand the calculation procedure without any questions.

A. Material calculation:

1.  Volume of  rubble stone:

The required vol. of stone

= [1.25 × the vol. of RR masonry wall]

= [1.25 × 157.5 cu ft.]

= 196.875 cu ft.

2. Cement mortar:

The required dry vol. of cement mortar

= 40% of the vol. of RR masonry.

= [40 × 157.5 cu ft. ÷ 100]

= 63 cu ft.

Let us build this wall in the cement mortar of 1:6 ratio

a.  The volume of the sand

= [{its ratio  ÷ ( total ratio)} × dry mortar vol.]

= [{6  ÷ ( 6 + 1)} × 63]

= [0.8571 × 63]

= 54 cu ft.   or

= 1.53 cum.

b. Volume of the cement

= [total dry mortar vol. - volume of sand]

= [63 cu ft. - 54 cu ft.]

= 9 cu ft.

As you know, one bag of cement = 1.226 cu ft.

Number of cement bags

= [9 cu ft. ÷ 1.226 cu ft.]

=   7.34 bags.

B.  Labor calculation:

The labor rate per cu ft. of the RR masonry work ranges from INR 10/- to 16/- depending upon the region.

Let us consider an average rate of INR 13/- per cu ft.

The total cost of labor for RR masonry

= total vol. of RR masonry in cu ft.  × labor rate/ cu ft.

= 157.5 cu ft. × 13/-

= INR 2,047.5/-

Now, let us calculate the total cost of RR masonry in table format.

 Sl. no. Item. Qty. Rate. in INR. Unit. Cost in INR. 1. Rubble stone 196.88 35/- Cu ft. 6,890.80 2. Cement 7.34 380/- bag 2,789.20 3. Sand 54.00 60/- Cu ft. 3,240.00 4. Curing Lump-sum 200.00 5. Miscellaneous Lump-sum 275.00 6. The material cost = 13,395.00 7. Add 5% wastage = 669.75 8. Total material cost = 14,064.75 9. Labour cost = 2047.50 10. The total cost of RR masonry wall = 16,112.25

Note: To get accurate results, insert your regional market rate of materials & labor, in the above table.

a. The cost of random rubble masonry/cu ft.

= [total RR masonry cost ÷ total masonry vol. in cu ft.]

= [16,112.25 ÷ 157.5]

= INR 102.30 /cu ft.

b. The cost of random rubble masonry/cum.

= [102.3 × 35.3147]

= INR 3,612.70 / cum.

( As 1cum = 35.3147 cu ft.)

Note:

If the work is handed over to any contractor, you have to add 10% extra for his profit.

If you have any quarries, you can ask me in the comment boxðŸ‘‡.