Tuesday, September 16, 2014

Material and Labour requirement for mixing (1:1 1/2: 3) G25 concrete

Mixing Concrete 1:1 ½:3 (3/4”) G25

Description
Unit
Quantity
Cement (50 kg Bags)
Nr
23
Sand
Cu
0.42
¾” Metal
Cu
0.82
Hire of Mixer
Day
0.333
Water
Gal
150
Skilled labourer
Day
0.333
Unskilled labourer
Day
2
Total



With the given information in the above table you will be able calculate unit rate for mixing concrete (1:1 ½:3) G25 by in putting particular market rates for each material and labour in your area. Once you established the unit rate you can estimate the total cost of G25 concrete work in your building or house or whatever the construction by unit rate multiplying with total quantity of work.

Note: When you do you calculation consider about the units. (Cu,Cum,etc.)




Calculation of material and labour requirement for rubble masonry incement mortar 1:5 in foundation

Random Rubble Masonry in Cement mortar 1:5 in foundation (1Cu)

Description
Unit
Quantity
6”-9” Rubble
Cu
1.3
Cement (50kg bags)
Nr
5
Sand
Cu
0.3
Water
Gal
100
Mason
Day
1
Unskilled labourer
Day
3
Total



Generally, to construct a rubble foundation, the materials required are rubble, cement, sand, and water. Mixing of cement and sand mortar ratio can be changed depending on the strength should obtain but the most frequently used ratio is 1:5 (cement:sand) mix, which we are going to discuss in this article.

In the above table, material and labour requirement for 1 Cube of rubble masonry work have been indicated based on the field experience and building schedules of rates. In this calculation, it is necessary to add 5-10% of wastage for sand. 

Ex:- Assume we have to construct a rubble foundation, which is 450mm in width, 600mm in height and which is 50m long. Assume water is available at the site. What are the material and amount of each material are we going to purchase to get the work done.

First, we need to calculate the total actual volume of rubble work.

 V = 0.45m x 0.6m x 50m
     = 13.5 m3
     = 4.77 cube 

According to table given,

Rubble = 4.77 x 1.3 Cube
             = 6.20 Cube

Cement = 4.77 x 5 Bags (50kg)
              = 23.85 Bags
              = 24 Bags

Sand = 4.77 x 0.3 Cube
         = 1.43 Cube

Add wastage 5% = 1.43 x 5%
                            = 0.07 Cube

Total Sand Requirement = 1.50 Cube

Therefore your Purchasing order should be;

Rubble = 6.20 Cu
Cement = 24 bags (50kg)
Sand = 1.50 Cu

Note: When we issue the payments for the labours, consider only the actual volume of rubble masonry and not the amount of purchasing of rubble.

Therefore, payment should be issued for labour for this work is 4.77 cu (Skilled labour days 4.77 and  unskilled labour days 14.31). 

Note: 1cube = 100 cu.ft = 2.83 cum


Typical Rubble Foundation Detail















Check Out the Rubble Masonry Calculator




Saturday, September 13, 2014

Material and Labour Requirement for Precast Concrete Slab for 1Sqr (=100 Sqft)


Material and Labour Requirement for Precast Concrete Slab for 1Sqr (=100 Sqft)

  • 2) 2” concrete topping (1:2:4), 1/4 chips = 0.17 Cu
  • 3) Cement = 6.5 x 0.17 = 1.12 bags (50kg)
  • 4)  Sand      = 0.5 x 0.17 = 0.09 Cu
  • 5)  Metal    = 0.88 x 0.17 = 0.15 Cu
  • 6)  Floor beams Placing at 2’ c/c = 100 Lft
  • 8)  Labour charges & Transport charges can be changed


Since Quantities have been given now you will be able to calculate the unit rate for the above work by inputting the material cost depending on your area.

Note: Consider about the unit conversions otherwise the calculations will go wrong.


                                    1 Cu = 2.83 Cum






Rate analysis for brickwork in construction

When we analyse a rate for construction work, we can get different answers according the previous records which have been recorded during c...