If you want to calculate reinforcement in construction project then you must pay your attention to these General Points for Calculations of Reinforcement.
1. For beam hook= (beam depth-both side covers)/2 for example if it is a 450mm depth beam then hook is (450-50)/2=200 where cover for beam is taken as 25 mm
2. For stirrups the hook=4d as per is codes but according to site conditions it is 50 mm per hook while doing bar bending schedule.
3. For slab the rod the crank length is l/5.
4. For beam the bottom extra is at l/6.
5. For slab the top extra extends till up to l/3.
6. For beam the top extra bar extends till l/3.
7. The column capitals extends till/4.
8. Where l is effective length of the beam. It is taken as center to center of the beam.
9. The crank length is 1.41d, where d is (depth of slab or beam- two side covers)