How to estimate steel quantity?

rameshchandrapatel

Active Member
Is there is any thumbrule for estimating amount of steel used in residential structures?

Ex 2.5kg/sqft.
Im giving here general steel requirement for different RCC members in kilogram per cubicmeter.
Column footings 75 kg/m3
Grade beams 100 kg/m3
Plinth beams 125 kg/m3
Main beams above 6m 250 kg/m3
Columns 225 kg/m3
Lintel beam 125 kg/m3
Sunshades 60 kg/m3
Canopy slab upto 2.0 m span 125 kg/m3
Staircase waist slab 150 kg/m3
Roof slab
(a) One way slab 80 kg/m3
(b) Two way slab 100 kg/m3
(c) Square slab – 4m to 6m size 150 kg/m3

slab area is 400 square meter, thickness of the slab is 150 mm.
Concrete quantity required to cast this slab is 400*0.15 = 60 Cubic meter.
After calculating concrete quantity, you can remember these thumb rules just for getting a basic idea of how much quantity of steel is required in those structural members.
Steel quantity in a conventional slab (excluding its beams) will be around 60 to 65 Kg per Cubic meter.
In beams it will be around 200 to 220 kg per cubic meter.
In columns it'll be around 200 to 250 kg per cubic meter.
For raft footings it'll be around 100 to 120 kg per cubic meter.

Thumb
M3*1.5*.7850
Its % of steel = 1.5
For slab 1.5
Beam 2.5
Column 3.5

2nd thumb rule is 2% of total concrete m3
 

Dnyan Deshmukh

Staff member
Thumb rule user should know, what he is using and for what and its effects.

Thumbrules are highly complicated thing just like share market. One should have knowledge about its processes before investing else may get huge losses on investment.

A blind peoples explaining how is elephant by touching it.
So one blind can say elephant is like bamboo stick by touching tail and another can say hard rock by touching to teeth. Story goes so on.

A good thumb rule maker knows how elephant is because he sees through his eyes and knows all details of it.(not all elephants are same to describe :lol:, basic may be same like conrete rebar etc but the structure and beauty will differ)

I hope i have explain in details on the effects of thumb rule.

So just dont be blind, see the specs and get idea on what kind of structure is and do calculation.

Good budget is one which do not differ by more than 20% from actual cost incurred.

Beyond 20% you might need to change your profession or need to learn more and more so you wont make owner a begger.
 

MAR

Founder Member
Im giving here general steel requirement for different RCC members in kilogram per cubicmeter.
Column footings 75 kg/m3
Grade beams 100 kg/m3
Plinth beams 125 kg/m3
Main beams above 6m 250 kg/m3
Columns 225 kg/m3
Lintel beam 125 kg/m3
Sunshades 60 kg/m3
Canopy slab upto 2.0 m span 125 kg/m3
Staircase waist slab 150 kg/m3
Roof slab
(a) One way slab 80 kg/m3
(b) Two way slab 100 kg/m3
(c) Square slab – 4m to 6m size 150 kg/m3

slab area is 400 square meter, thickness of the slab is 150 mm.
Concrete quantity required to cast this slab is 400*0.15 = 60 Cubic meter.
After calculating concrete quantity, you can remember these thumb rules just for getting a basic idea of how much quantity of steel is required in those structural members.
Steel quantity in a conventional slab (excluding its beams) will be around 60 to 65 Kg per Cubic meter.
In beams it will be around 200 to 220 kg per cubic meter.
In columns it'll be around 200 to 250 kg per cubic meter.
For raft footings it'll be around 100 to 120 kg per cubic meter.

Thumb
M3*1.5*.7850
Its % of steel = 1.5
For slab 1.5
Beam 2.5
Column 3.5

2nd thumb rule is 2% of total concrete m3


Thank you very much for sharing such a valuable information. I think the above thumb rule is applicable only to Residential Structures, where as in case of other type of structures it varies from building to building
 
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amd007

Elite Member
Thumb rule user should know, what he is using and for what and its effects.

Thumbrules are highly complicated thing just like share market. One should have knowledge about its processes before investing else may get huge losses on investment.

A blind peoples explaining how is elephant by touching it.
So one blind can say elephant is like bamboo stick by touching tail and another can say hard rock by touching to teeth. Story goes so on.

A good thumb rule maker knows how elephant is because he sees through his eyes and knows all details of it.(not all elephants are same to describe :lol:, basic may be same like conrete rebar etc but the structure and beauty will differ)

I hope i have explain in details on the effects of thumb rule.

So just dont be blind, see the specs and get idea on what kind of structure is and do calculation.

Good budget is one which do not differ by more than 20% from actual cost incurred.

Beyond 20% you might need to change your profession or need to learn more and more so you wont make owner a begger.

Well said Dynan. 👍