"'Mike'" wrote in message
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"Bender" wrote in message
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Hi
Just a quick question if anyone has the time to answer
How many 25kg bags of ballast/cement to mix 1 cubic metre of concrete?
Assuming a mix of 4:1 ballast:concrete
I'm laying a base for a greenhouse and need about 3 cubic metres of
concrete but I need to know how many bags of ballast/cement to order.
I would have ordered in ready-mix but its just too far away from the
drive to barrow/pump.
Many thanks in advance
-Iain


3 Cubic Metres?

THREE?

That is one hell of a lot of concrete. Me thinks you have something wrong
there.

Google says the density of concrete is about 2400 kg/m3 so it looks he
needs 7200 Kg or 288 x 25 Kg bags! (Actually less than that if you allow for
the water. Either way I wouldn't want that in the back of my car :-)

Lets say his house is 4 x 3 M and 150mm thick = 1.8 cubic meters. .So 3
cubic does sound a lot.