Garage base help needed

[terminator99]

Hi,

I am building a concrete base for a 3m by 5m garage, its 8 inches deep. And i plan to use a 2:11 mix of cement and ballast.
I've read many guides on how to do this and there is a few things i'm not sure about and i was hoping you guys could help with that?

1) Some of the guides said that after you lay the mix you need to "water" it for upto 2 weeks afterwards. Some suggested using hesian sacking over the top of the mix and to keep the sacking wet. Is this really needed?? Apparently its to stop it from cracking?

2) Because of the size of the base i think it would be too much to do in 1 day, so i was thinking of doing the base in 2 sections. So i was wondering if there are any reasons why i shouldn't do it in 2 sections? Is it likely that 1 section might move leaving the base uneven?

Thanks for your time!

 

[Static]

1) yes prevents slab drying out too quick and thus forming small hairline cracks in the surface.
2) can be done in 2 pours with the proper construction joint

 

[noseall]

concrete behaves better in cooler temperatures as it doesn't dry out too rapidly.
cooler temperatures (not sub zero) mean a higher success rate with hydration too.
so if it is in the mid 30's (celsius) then manual wetting or damp sacking is used to keep the concrete cool.
lower temperatures doesn't usually warrant such diligence.

external concrete or concrete that is subject to warming by the sun and cooling at night is best laid in sections with expansion joints in between.
this will help prevent cracking.

internal floor slabs are usually laid in one hit, as a join in the concrete may prove to be annoying in the future.

mix the concrete, 6 parts ballast/sharp sand mix to 1 cement.

plus if you are on clay sub soil and if there are any trees near by, then clay heave may be a factor to consider.

 

[terminator99]

Thanks for the fast replys!
That just about answers my questions, i just have to wait for some nice weather now

 

[noseall]

Thanks for the fast replys!

yeah.....me 'n' Static are just waitin' by our key boards in anticipation of your questions.

only Static's quicker 'n' me.

 

[Static]

Thanks for the fast replys!

yeah.....me 'n' Static are just waitin' by our key boards in anticipation of your questions.

only Static's quicker 'n' me.

Or more bored

 

[NS215]

why not get the barrow mix boys in and get it all done in one day