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Posted: Wed Jun 02, 2010 9:27 am
by DEfusion
I've begun laying a path (10m x 1.2m) that begins on a slope (7.5 degrees) until about half way where we're going to put a step and then the rest is going to be flat.

We're using riven Indian sandstone and the methods described on this site using a 10:1 mix of sharp sand & cement as the bedding layer. However I have not been comfortable enough yet to butter the stones as I've been bedding them, plus we were not going to be able to lay the entire length of the path in one visit.

My questions are:

1) Will I have issues with this method on the slope, e.g. will there be potential movement of the stones due to the force from walking being applied at an angle? Should I be maybe mixing the bedding layer a bit stronger so that it is a bit more ridgid?

2) Is my reluctance to butter the stones as I go going to be a problem or will a solid motoring/pointing after the laying be enough?

So far we've only laid 4 big stones to start this path (so only 1.2m of the length) as we spent most of the weekend on the prep. But after we first attempted to lay them we noticed that further pressure caused them to become rocky again after levelling them out (and removing all the rocking). I assumed this was because we should have been staying off them more than we were so when we re-laid them we stayed off them completely. But afterwards I was wondering if the buttering would have stopped this?

Posted: Wed Jun 02, 2010 7:17 pm
by mickg
my answers are

1) use 4:1 mix, 10:1 is too week a mixture

2) use an SBR on the back side of the flags to form a bond bridge

3) use a wettish mix so the SBR and the bedding layer bond together

4) you can't walk on the flags you have laid until the following day and even then you need to proceed with care and caution otherwise you will have rocking flags

note: wettish is when you have added enough water to bind the mixture together, get a handful out of your mixer and when you squeeze it will stay in a ball and not disintegrate between your fingers, plus if its too wet then your flags will sink into the mixture

you need to wear gloves when handling a sand and cement mixture otherwise the cement can burn your skin