How to build a shed base?

marybro

hi all,

so I’ve brought this shed and is yet to be assembled my question is my yard is hard granite and not even,I don’t know where to start…how do I make sure the ground is level?

what should I use cost wise? pavers or cement ?( I will be doing this all myself as I live remote)

im determined to do it myself as my son says I can’t ,I own my own home so I want the shed permanent and the flooring doesn’t have to look pretty. But I do need it to stay in place in case of winds. I have “googled” but it’s overwhelming.

”we not fancy, but we cheap” vibe is what I’m going for…thanks guys 

EricL

Hello @marybro 

Welcome to the Bunnings Workshop community. It's sensational to have you join us and thanks for sharing your question about building a shed base.

Shed manufacturers often state "The shed shall be erected on top of a reinforced concrete slab and anchored down appropriately." Since your shed is not so big, it is still possible to build this shed base yourself. I suggest having a look at this guide - How to pour a concrete slab by @tom_builds. It's an excellent example of how you can pour your own slab without being overwhelmed by the task. It does help of course if there is a second pair of hands to help with mixing the cement. However, if the budget allows for a cement mixer hire, it would make the job go a lot faster.

For a concrete base measuring 1090mm x 1830mm x 90mm, you first need to determine the total volume of concrete required. By converting the measurements to metres, the volume is calculated as 1.09m × 1.83m × 0.09m, which equals 0.179 cubic metres (m³). Since you’re using premixed concrete, which is a dry blend of cement, sand, and aggregate that only requires water, the next step is figuring out how many bags are needed.
 

A standard 20kg bag of premixed concrete typically yields about 0.009m³ of mixed concrete when water is added. To find the number of bags required, you divide the total volume needed by the volume per bag: 0.179 ÷ 0.009 = 19.9 bags. Since you can’t buy a fraction of a bag, you should round up to at least 20 bags.
 

It’s always a good idea to get an extra bag or two in case of minor spills, inconsistencies in mixing, or if you find yourself a little short. When mixing, it’s best to add water gradually until you achieve a workable consistency—too much water will weaken the final concrete. If you're working in hot or dry conditions, try to mix and pour in the cooler parts of the day and keep the surface damp during curing to prevent premature drying and cracking. 

If for example, you were to use the Bastion 20kg Premix Concrete or similar, it would cost you $9.14 a bag. Since you need 20+2 extra that would be 22 bags for a total of $201.08. Since it is a proper base, you are covered for the warranty, and you can properly anchor the shed to the floor. 

If you need further assistance, please let us know.

Eric