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Garden shed floor slab

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Garden shed floor slab

I want to build a 3m x 3m shed in the end of my garden - bad access due to existing shrubs . How to go about constructing a concrete slab.



Bunnings Team Member
Bunnings Team Member

Re: Garden shed floor slab

Welcome to the Bunnings Workshop community @Duffy. It's sensational to have you join us and many thanks for your question on concrete slab construction.


You might like to read through these previous topics about shed bases:







You should find these step-by-step guides useful when building your concrete slab: How to build formworkHow to mix concrete and How to level concrete.


The first step will be clearing the area of debris and cutting back those existing shrubs. Ensure the ground is solid and compact if necessary. Next, you'll establish your formwork. Cutting strips of Specrite Formply F17 1800 x 1200 x 17mm Plywood can be an inexpensive option and Growies 50 x 50mm 450mm Hardwood Steel Cap Garden Stakes make great pegs for holding it in position. Whites On-Site 1800 x 1050 x 5mm Light Duty Reo Mesh is placed upon Whites On-Site 50-65mm Plastic Reinforcing Bar Chairs 100 Pack in the middle of the area to prevent the slab from cracking.


The amount of concrete you'll need can be worked out once you decide on the thickness of your slab. A suitable thickness for a shed slab would typically be 100mm.


Some tools you'll find useful in laying a concrete slab are a concrete mixerglovessafety glasseswheelbarrowshovelscreedfloattape measurelevel, and buckets.


Please let me know if you have any questions.




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