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How much concrete do I need for 3.5m slab?

Budding Browser

How much concrete do I need for 3.5m slab?


I’m going to do the concert slab of 3.5m x 3.5m it comes up to 1.22 Quebec m2 with 100mm thickness can anyone suggest me how much concrete mix does it requires and what is the easiest way to do. Suggestion are really appreciated thanks.



Community Manager
Community Manager

Re: How much concrete do I need for 3.5m slab?

Welcome to the Bunnings Workshop community Aziz (@azizsyed01). We're pleased to have you join us and look forward to seeing you complete your concrete slab project. 


Check out this helpful step-by-step guide by experienced Workshop member @tom_builds: How to pour a concrete slab. It should be really helpful to you.


The normal ratio for concrete is 1 part cement, 2 parts sand, and 3 parts gravel. So, for every bag of cement you'd need, you'll use two bags of sand and three bags of gravel. Here's a calculator from one of our suppliers that you can use to calculate how much is required. 


Hope that helps get you started. Let us know if you have more specific questions. We're here to help.




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