How to decide beam size

According to IS-13920

Beam Depth ⇒ $\frac{L}{12}$ to $\frac{L}{10}$

ex if a length = 6m

$\frac{500}{12}$ or $\frac{600}{12}$

Let’s take 600 mm [500mm or 600]
Beam width ⇒ $\frac{D}{1.5}$

considering above = $\frac{600}{1.5}$ = 400mm

Please Note:

200 mm ≤ Beam width

Never design a Beam width less than 200 mm.

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