Share
Welcome to the Bunnings Workshop community @x1234. It's great to have you join us, and many thanks for your question about concrete volume.
In order to work out coverage, we'd need to know the intended thickness. The volume of one 20kg bag is around 0.01m3 or 100 bags for 1m3. Here's a helpful set of calculators to work out the required number of concrete bags for your project.
Please let me know if you have any questions.
Mitchell
