Question 1

How many 20 kg bags make one cubic metre?

Accepted Answer

Under this calculator's yield, one 20 kg bag gives about 0.00856 m³, so roughly 117 bags per m³ before any extra allowance.

Question 2

How long before I can walk on a slab?

Accepted Answer

Often about a day for light foot traffic, but strength keeps developing for weeks; keep it moist and follow the product guidance.

Question 3

Can I pour a column with premix bags?

Accepted Answer

For small piers, yes, but pour in layers and compact each layer to avoid voids.

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