How much will mot compact - Patio base

[Just]

Hi all some advice please, I am setting up my base for a patio which is 7.5m x 3m I have approx 100mm MOT which I am going to plate, I don't want to hire the plate until most of the stone is down and so I am trying to guess the finished height of the compressed stone which will be approx 90mm below DPC. Can anyone tell me how far MOT crusher run will Whacker plate down so that I can add this on to my loose stone height? I hear 60:1 is okay for end fall on a patio, can I get away with less than this, situation wise less would be better? Slabs will be Indian Stone. Thanks!

[henpecked]

Wouldnt be worried about getting 100mm exactly. Mot will compact a little, but not much. If your short, you can make it up with the screed.
Ive just laid a load f riven Indian stone, and as the back of the slab was so variable, it didnt really matter too much how spot on I was with sub base

Best o luck!.

Hp

[Just]

Thanks for the advice, the thing is I need the slabs exactly two bricks below dpc as any higher is not good and below will see blockwork and is unsightly I don't want to use too much sand and cement so was trying to get an estimate of how much the stone will pack down prior to hiring the plate?

[GB_Groundworks]

your finished patio needs to be at least 150mm below dpc

[henpecked]

You can play with up to 60mm sand screed ,so your margin of error is good.
As you can imagine, you can get a good guestimate of how much bedding you have put down with a string line across the area, too much, rake it over, too little put more on. Using the calculator to the main site you will get a very accurate quant for you sub-base.

Hp

[mickg]

the MOT type 1 will compress approx 10mm - 15 mm and yes you do need a fall of 1:60 otherwise you will end up with large puddles of water on your patio as indian is not flat