What is the grade of concrete(M20/M25 etc.) normally used in roof casting? How much PSC cement is required for making 1 cubic meter of concrete?

Question

I am building a small construction of about 700 square foot(picture attached). In roof casting my mason has used 60 bags of PSC cement though he estimated 74 bags before. I am in serious doubt what is going on. Could you please help me?


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Concrete Pal Chakraborty 9 months 7 Answer 18358 views