Laying a patio circle

[paul24dual]

Stupid question.

Hi everyone, i'm currently laying a patio circle and need some advise. I've dug about 200mm deep for the foundations but is this too much?

40mm - Flags

75mm - Hardcore

40mm - Cement

= 155mm

Can i just use more hardcore or shall i put some soil back to build it up slightly again?


Thanks

Paul

 

[cannonfoder]

best way to do it are you planning to hire a whacker to compact the base?
if so you can ether peg it out soo the top of the peg is level to the finished flag height.
then mark off the depth of flag mortar bed an hardcore you can chuck in some earth an rake off an whack or even just chuck in some hardcore wont hurt you loose about. 10%if your using mot type 1 stone an a whacker..

 

[r896neo]

Don't put soil back in, only bring up the level with more hardcore.

If its uber sandy soil it may re compact ok but putting dug out soil back in is poor practise.

 

[paul24dual]

Thanks for the reply. Does the soil have to be perfectly level? And how do i level the hardcore?

 

[r896neo]

Just level the hardcore with a rake and set your fall into the hardcore sub base.

The soil doesn't need to be perfectly level, plus or minus and inch will be ok.

Set a string line to your finished height and take dips off that to check the levels

 

[paul24dual]

I've put the sub base down. I'm i right in saying that this does not have to be perfectly level because i can level the flags up with the mortar? Also there seems to be a lot of "bigger" stones from the hardcore around the outside of the base that will not compact as much. Any advice would be welcomed.

 

[r896neo]

You can usually get it to plus or minus 15mm fairly easily and that should do ok.

The big stones sounds like your type 1 was rubbish and may have been recycled or type 2 which is less graded.

As long as you have plated the whole area at least 10 times it should be fine but you can't over compact it so go nuts.

A small light plate will always struggle with larger stone.

 

[paul24dual]

Thanks for the reply. I've gone over it about 10 times and it seems to have settled. Another question if thats ok? I have put a string line and layed a stone on the base, the distance from the line to the top of the flag is 2 inches.

Will a 2 inch mortar base be ok? or should i add more hardcore?

 

[r896neo]

2'' is good. Anything between 30 and 50mm is fine so if you have a bit more hardcore and want to bring it up 10mm then you'll have a bit less mortar to mix.

 

[paul24dual]

The circle is down and i'm pretty pleased with it, the only thing is that a couple of the slabs there is a very very slight wobble, nothing major. is there anyway of fixing this easily or will it be ok?

 

[r896neo]

if they rock at all now they must be lifted and re-bedded (meaning the bedding needs removed and renewed.

A rocking slab will never right itself and will crack the pointing in no time.

 

[paul24dual]

shame really, i thought i had done a good job!!

is it because i have just laid it and its needs to set?

it only very slightly rocks in one corner on 2 slabs. and these are not the slabs that will not be walked on. would you still fix or shall i see what it is like tomorrow?

 

[r896neo]

bite the bullet and fix it. It is nothing to do with curing or hardening, it was just laid incorrectly or got leaned/walked on before it had firmed up

 

[paul24dual]

it the flags in the centre. how do i get these out without disturbing the outer flags?

 

[r896neo]

it it hasn't been pointed yet then i would imagine they will prise up relatively easily. to avoid disturbing the bedding and loosening other flags you may have to cut the bedding out with a stihl saw or grinder.