Ticker

6/recent/ticker-posts

Estimating & Costing - Basic Measurement

Estimate :-

It is the probable cost of any project/ work with specified time & conditions.

Following are the various types of estimate:

1)Approximate estimate/Rough/ abstract estimate-

•It is used for the basic information of any project & failure financial planning.

2)Plinth Area Estimate-

• This method is based upon 2 dimensions (LxB) Mainly.

• It is the built up covered area.

3)Cube Rate estimate-

• this estimate is based upon cubical dimension (LxBxH) of the work.

• This method is much better as compared to previous method.

4)Detailed estimate-

• This is the most accurate method.

• It is generally occurred in 2 stages

1. Measurement of work/dimension.

2. Abstract of estimate with the help of prices.


Soling-

It is the process of making the base for concrete work/other work. by using layers of dry brick (Stones)

Brick size

Normal → 20x10x10 cm

Modular → 19x9x9 cm

Standard

Traditional

Non-std.                       ←23 x 11.5 x 7.6 cm

Field                       

Conventional

No of bricks used in 

Edge soling = 1m2/0.23x0.076          (LxH)

Flat soling = 1m2/0.23x0.115             (LxB)


DPC – Damp proof course

         Cement sand Aggregate

M10        1 : 3 : 6

M15        1 : 2 : 4

M20        1 : 1.5 : 3

M25        1 : 1 : 2

• DPC is measured in m2/Area

• It is used to prevent the moisture & provided at plinth level.

• The general thickness of DPC is about 2 to 2.5 cm. with suitable grade of concrete (M15 to m20) having Water repellent agent (bitumen etc)


Earth work

• Earth work is measured in m3

• If any valuable material found during excavation then it will be property of government of india.

• It the depth of excavation is less than 30cm then excavation will be surface/shallow excavation & it is measured in m2

• The general lead & lift in excavation is about 30m & 1.5m respectively.

• in foundation, we use lean/weak concrete.


Stone & Brick Work

• It is generally measured in m3

• if the thickness of wall is 10cm, then brick work is measured in m2

• Dressing of stone is measured in m2


Steel and Iron work

• Density of steel is 7850kg/m3

• generally amount of R/F (only in steel) is 0.6 to 1% of total RCC volume

• The weight of a steel bar per meter length is calculated be following formula -

d2/162    Kg/m

Where d = dia of bar in mm.


Plastering and pointing

• It is Measured in m2

• The thickness of plaster is about 12mm

• Following are the deduction conditions for the area of opening in the plaster work.

1)if the area of opening ➔ < 0.5 m2 ➔ No deduction

2)If the area of opening ➔ 0.5 - 3 m2 ➔ One side deduction

3)if the area of opening ➔ > 3m2 ➔ Both side deduction for the payment

Note:- 1) In RCC work, PCC work, R/F brick work are measured in m3

2)Jaali work, rolling shutter, plywood, net wiring, laminated board are measured in m2

3)Generally woodwork is measured in m3


Degree of accuracy in estimation

• Wood work should be measured to nearest 2mm.

• Weight should be measured to nearest 1kg or 0.001 Tonn

• thickness of slab should be measured to nearest ½ cm.

• Generally dimension should be measured to nearest .01m, Area – 0.01m2 & Volume – 0.01m3 


Click here →

If you are a Civil engineer, you need to know... 

Reactions

Post a Comment

0 Comments