The bedding layer's described on this site reccommend a virtually dry mix ... what is the reasoning behind this over say a stiff wet mix?
I am laying indian stone flags and it would seem a wet mix may be easier to tamp down etc?
TIA,
Alex.
Wet or dry mix - Mix type ?
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wynyard
- Posts: 6
- Joined: Sun Jun 12, 2005 7:55 pm
- Location: Middlesbrough
Don’t know if this is of any help but I have just had a stone flagged patio laid and the laying instructions stated that the flags had to be laid on a wet-mix. The contractor doing the job said the disadvantage of this was that they could not be walked on until the mix had gone off but that it was necessary to have a wet and fairly loose mix to allow for the difference in bed thickness of the flags: the difference in the thickness of some flags was stark. Good luck and the only other comment I would make is that natural stone looks great and the imperfections make it more so to my eye.
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AlexW
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- Joined: Fri Jul 22, 2005 4:24 pm
- Location: Northwest England
This sounds sensible to me.
Builder I was talking too recently suggested wet mix would be easier to get solid bedding, but did not really qualify why.
I did a few flags like this as a test and it seemed OK on a wet mix ... easy to tamp the flag down to the correct level / pitch (unless you go too far!)
Thanks,
Alex.
Builder I was talking too recently suggested wet mix would be easier to get solid bedding, but did not really qualify why.
I did a few flags like this as a test and it seemed OK on a wet mix ... easy to tamp the flag down to the correct level / pitch (unless you go too far!)
Thanks,
Alex.
~Alex~
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Tony McC
- Site Admin
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It's largely a matter of personal preference. Wet mixes are all well and good, and they are probably easier to work with for absolute newbies but I don't like to work with them because....
1 - as already mentioned, it is at least 24 hours, preferably 72-120 hours before they can be used. Vehicles should be kept off for at least a full week.
2 - wet mix is messy. It has a nasty habit of getting picked up on the soles of your boots and tread all over the flags, meaning they all have to be cleaned on completion.
3 - there's a problem of overly wet mixes carrying cement through the flags and creating a 'hazing' phenomenon on the surface, and it's also been noticed that 'picture framing' (the appearance of a stained edge to freshly laid flags) is often more pronounced with flags laid on a wet mix, but can be absent all together on flags laid with a semi-dry mix.
4 - you have reduced working time with a wet mix
5 - wet mixes tend to bond to the underside of the flags, so if any remedial work is required, the damned mortar has to be chiselled off the bottom of the flags before they can be re-used.
...I'd rather see a wet mix used than a spot bed, and I would never condemn anyone for working that way, but for me, it's more bloody trouble than its worth - horses for courses, as they say.
1 - as already mentioned, it is at least 24 hours, preferably 72-120 hours before they can be used. Vehicles should be kept off for at least a full week.
2 - wet mix is messy. It has a nasty habit of getting picked up on the soles of your boots and tread all over the flags, meaning they all have to be cleaned on completion.
3 - there's a problem of overly wet mixes carrying cement through the flags and creating a 'hazing' phenomenon on the surface, and it's also been noticed that 'picture framing' (the appearance of a stained edge to freshly laid flags) is often more pronounced with flags laid on a wet mix, but can be absent all together on flags laid with a semi-dry mix.
4 - you have reduced working time with a wet mix
5 - wet mixes tend to bond to the underside of the flags, so if any remedial work is required, the damned mortar has to be chiselled off the bottom of the flags before they can be re-used.
...I'd rather see a wet mix used than a spot bed, and I would never condemn anyone for working that way, but for me, it's more bloody trouble than its worth - horses for courses, as they say.
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