Global stone calibrated paving nightmare - Calibrated paving

[mark bow]

Global Stone Calibrated Paving Nightmare

I've done it as the manufacturers specify a sand cement screed bed for their sandstone paving project packs
I think the problem is the sand is very wet I did not compact it but walked over it then compacted with a spade
Approximately 2.8 m x 3 m and screed it off as normal the problem is they will not sit without rocking no matter what
The saw marks are only here and there with lots of low points should I continue using a normal mortar bed
After all the problems today I've had to rake of the screed bed and spread it about
Your advice would be very much appreciated and thank you in advance
I have no problem normally with most paving although I have never used this
Mark

[lutonlagerlout]

mark nearly all paving should be laid on a sand and cement bed
but 90% of the blokes on here use lines and lay each flag individually
even calibrated stuff has +/- 5 mm in thickness

global's stone is normally pretty good but i would never contemplate laying it on a screed

I normally use bricklaying consistency mortar and lay 1 at a time,making sure to wash any mortar splashes off with clean water as I go

btw the mortar should be 6:1 sharp sand(screeding sand) to cement
hope this helps

cheers LLL

[mark bow]

Hi lutonlagerlout
Thank you for your reply I would normally use a full mortar bed I phoned global stone mainly because didn't seem correct to me
And they said a sand cement screed bed was the correct way to put the paving down won't be doing that again what is down is okay but since I started on the other free project packs
There is big variations in some slabs only have a few saw marks
Contemplating continuing with full mortar bed
As I do not want to rip up 15 m² and it seems okay no rocking
Also they are a riven paving
Mark

[lutonlagerlout]

holy moly
I have global stone modak rose on my own patio at home and there is no way I would consider laying riven flags on a screed

apart from small unit concrete slabs and council greys nothing should be laid on a screed due to tolerance
good luck with the weather

LLL

[mark bow]

I should of had more sense than to listen to manufacturers ,it wasn't long ago that Marshalls advise was to use spot mortar bedding.
I was rained off Thursday and on Friday as it was my birthday had a long weekend off now back to work Tuesday and so is the rain
Will continue with full mortar bed but will have lots to catch up pointing to do is approximately 50 m² of paving
I would normally give the paving a good soaking the night before pointing and spray in the joints with a 4 to 1 with PVA prior to pointing is this best way, your advice welcome
many thanks
Mark

Below is taken from the manufacturers website
http://www.globalstonepaving.co.uk/installation-guide.html
Global Stone Types of Paving
Calibrated Paving
The technique known as ‘screeding’ is used to prepare the bed for calibrated paving. Use a shovel to spread the freshly-mixed bedding material over the area, large enough for several paving stones in a layer that is roughly 40-60mm thick, and pat it with the back of the shovel to lightly compact it. It is important to use ‘not too much’ of the bedding, because it has to be scraped off, using a long, straight board to remove the excess bedding material, leaving a smooth and level surface onto which the paving can be placed. To achieve the correct level for the screeded bed, a reference level is required. This might be an existing edge (or kerb or edge course) or it can be a ‘rail’ set at the level of the underside of the paving.

[DempseyLiverpool]

PVA is no good for exterior work you need SBR. Might be worth using weatherpoint 365 or similar this time of year. Or a rapid set mortar.

You'll be lucky to be able to pre wet, prime and point this time of year. Where you going to knock up your own ?

I always lay individually especially natural stone

[mark bow]

Hi Dempsey
Thank you for your reply yes I am knocking up my own
Can I spray SBR in the joints with a 4 to 1 mix or should it be a different mix.I have got it on the job anyway
Many thanks
Mark

[DempseyLiverpool]

You would have to be very careful not to stain the paving.

I only use it for bond bridge or added to bedding and pointing mix