How much concrete mix bags of 30kg do I need to build a concrete slab for a shed. The slab will be 8x9, 4inch

Question

The slab is about 8x9 and about 4 inch thick

Thanks

Answer 1

Tony I think you will get about 1.5 sq. ft. per bag. This comes to about 48 bags.  I would look for some rocks to put in, and you should get by with about 40 bags.

Good Luck

Answer 2

This is a good caculator

Good Luck