Answer:
Deflection of a beam depends on the following parameters:
1.Modulus of Elasticity of steel 200kN/sq. m
2. Moment of Inertia of the beam section
3. Effective Span of the beam
4. Applied load
Minimum thickness recommended is 6mm, from consideration of corrosion etc. however, minimum Structural steel section of thickness may be used provided they satisfy strength and durability requirements.