Shed base - How much ballast & cement?

[Julesx]

Can anyone help out an enthusiastic bodger?!

I have a shed base that I would like to extend. I want to make it 1m x 3m wider along one side and 2m x 3m on one end

I understand that it will need to be 150mm deep - the old one is this deep.

My plan was to have ballast delivered in big sacks and use my old mixer.

Question is - I am going around in circles with these on line calculators!


I think I need 1.35 t of ballast - Do you think that is correct. Bit of pain because that means two 1 ton bags (or I suppose one big bag and the rest in smaller ones to save wastage and having to dispose of the left overs?)

But I cannot work out how many bags of cement (are they 25KG?) that I will need. Anyone give me an idea on my calculations.....................?

Many thanks

Jules

 

[noseall]

Your 1.35 figure is the quantity in metres cubed.

This equates to roughly 2.7 tonnes of ballast, or for the sake of quantity ordering = three tonne sacks of ballast.

You will also need aboot 18 x 25kg bags of dust.

If you wanted to get say 2.5 tonnes of gear (16 bags of cement) and make the base slightly thinner, it wouldn't be a problem.

 

[Julesx]

Thanks very much - it seems that Wickes jumbo bags are 850kg so three of them might be just what I need at £38 per bag. That would give me the 2.5 tonnes figure that you mentioned. They have cement at £3.83 at the moment on offer.

I'm guessing that a slightly thinner base for a shed is OK?