garage base??

[dawesy1700]

hellloooo, im laying the dolomite for my new garage base this weekend but im having trouble finding out how much cement ill be needing, can anyone on here help please? the base is 5 inches deep, 12ft x 32ft, we'll be doing a strong, 5-1 mix and the sand and gravel mix will be getting delivered in 1.1T loads, the cement bags are 25kgs, are they any builders on here that could offer advice? i've spent 6 weeks designing the garage and now im stuck on the slab of concrete its gonna sit on, any help muchly appreciated.

[Jiffer]

you have about 36m2 of area and at 5" or 125mm thick you need about 4.5 cubic metres of concrete, you can have it delivered on a volumetric (mix on site) wagon for arround £70 per cubic metre.

if your going to mix yourself you would need about 8-10 bags of cement (portland or general purpose)per ton of mixed ballast.

I would say to put in some reinforcing mesh A142 would be fine and if you have some thin gauge polythene put this underneath not so much to act as a dpm but to stop the sub base sucking all the moisture out of the concrete which will cause cracking and if possible borrow or hire a pole float to give a nicer finish.

[dawesy1700]

ah right, thanks, what would that lot equate to in tons of ballast? how many would you order? and ive sorted the sheet for the concrete to go on top of.

[oxb1l]

Don't make the mistake i did with having my base level with the garden ,i have a water feature every time it rains (a lot )

 

L8r Bill (i went for delivery in a mixer)

[Jiffer]

not much of an exact science because concrete is worked in cubic metres but I would say about 7 ton of mixed ballast

[dawesy1700]

sweet, it at least gives me a clue as to waht to work towards. and as for the leveling of it, its level with the earth,

[Jiffer]

sweet, it at least gives me a clue as to waht to work towards. and as for the leveling of it, its level with the earth,

spend plenty off time getting the shuttering level and square, if you start up p1ssed you will end up p1ssed