pre mixed or self mixed concrete

[snico]

I am about to start digging the footings for a retaining wall.

I have been advised to dig a trench 12" x 12" for the wall to be then filled with concrete

Is premixed concrete from a builders merchant ok to use for the footings?
or shall I get myself some gravel, sand and cement............or cement and ballast?

I have a mixer so mixing it all is not going to be a problem. I have been told for the strongest foundations to use a ratio of 5:1 ballast and cement?

Any advise on the best way to go about this and the best mix

Steve

 

[Thermo]

Use cement and ballast. 6:1 is normally fine

 

[snico]

Cheers Thermo, would a 5:1 be actually more brittle or would it be the 6:1 I'm going to be putting rebar in anyway but i need this to be super strong! there is going to be quite a lot weight behind it eventually