Concrete covers in slab, Beam, Column and Footing,

What is concrete covers :- It is design depth of steel from the exposed surface of concrete. It is the dimension used in the design and indicated ion the drawing.
It should not be less then the Diameter of Bar.

Requirement of concrete cover :- It is provided to protect the steel bars from corrosion depends upon the quality of concrete.

Nominal cover in the COLUMN should not less then 40mm

Nominal cover in the FOOTING should not less then 50mm

Nominal cover in the SLAB should not less then 15mm

Cover in the BEAM is  should not less then the 25mm

The minimum Cover is depends upon the exposer condition of concrete.


  Exposure                    -        Nominal concrete cover in mm not less then

(1).  Mind                     -                                   20
(2).  Moderate              -                                   30
(3).  Sever                    -                                   45
(4).  Very sever            -                                   50    
(5).  Extreme                -                                   75

Note:-
(1). In Mild exposer rainforcement up to 12mm bars normal cover may e reduced by 5mm.
(2). Foe sever and very sever expose reduction of 5mm is made where grade of concrete is M35 and above.