Laying 20mm sandstone flags on a patio.

[Skyedriver]

Paving has arrived, the base is down and ready for the flags.

But I can't decide whether to lay them on a wet 1:3 cement:sand mortar (full bed not dots) or on a dry cement sand screed and allow the moisture in the ground to set the bed. The dry screed will be a little easier as I'm not humping wet mortar about.

Any advice from those who have done it before please?

[B17NNS]

Solid wet bed. Lick of SBR slurry on the back before you place them.

[magooagain]

Above is all the advice you need.

[paulwirral]

I'm doing one for a mate at this very moment in the method you've just been told to , the only difference is that I always mix fibre glass strands into the mix just to re enforce the bed .

[sandman77]

Definitely a wet bed but use a 6:1 mix.

[ColinM50]

SBR??????

[B17NNS]

ColinM50 said:

SBR??????

https://www.wickes.co.uk/Sika-Bond-SBR%2B-Waterproof-Bonding-Agent-Admixture---5l/p/133789

Mix with cement to create a slurry. Paint the backs of the paving before tapping home onto the bed.

[wolfracesonic]

...and if you splash the SBR slurry anywhere it shouldn't be, wash it off STRAIGHT AWAY!!!

[m3jappa]

I lay them on a 5:1 solid wet bed, add a bit of febmix to the mix as well so its properly wet and workable to allow adhesion. I have also started using a sbr and cement slurry to the back of all paving.
Initially it was just porcelain but it seems anyone who gives a st and anyone who doesnt want to go back and fix 2 loose slabs is now using it as well.

As mentioned make sure you get that slurry off the slabs as you will not remove it otherwise! Oh and if it gets on your hands or body look forward to having grey hands/body for at least a week

[Skyedriver]

Thanks for the guidance

Re SBR: Up here in Oban we are a bit shot of a Wickes or most others TBH.
Homebase list it but Oban is out of stock, Jewson don't list it.
Will stall the project and see if Homebase can get it in, failing that mail order....

[Skyedriver]

Just been looking, ToolStation do an SBR by Everbuild, a rubber based bonding agent, same thing?

[B17NNS]

Skyedriver said:

Just been looking, ToolStation do an SBR by Everbuild, a rubber based bonding agent, same thing?

Styrene butadiene rubber

[Skyedriver]

B17NNS said:

Skyedriver said:

Just been looking, ToolStation do an SBR by Everbuild, a rubber based bonding agent, same thing?

Styrene butadiene rubber

OK same thing thanks

[timmymagic73]

Good advice above, exactly how I laid mine.

What colour are the slabs? Mine were very pale cream so I used snowcrete (or equivalent) to prevent any bleed-through of the darker cement pigment.

Just in case.

[Vanordinaire]

Skyedriver said:

Thanks for the guidance

Re SBR: Up here in Oban we are a bit shot of a Wickes or most others TBH.
Homebase list it but Oban is out of stock, Jewson don't list it.
Will stall the project and see if Homebase can get it in, failing that mail order....

Jewson do stock SBR . I think it's listed as Cemflo Rendabond or something similar.

[Skyedriver]

Vanordinaire said:

Skyedriver said:

Thanks for the guidance

Re SBR: Up here in Oban we are a bit shot of a Wickes or most others TBH.
Homebase list it but Oban is out of stock, Jewson don't list it.
Will stall the project and see if Homebase can get it in, failing that mail order....

Jewson do stock SBR . I think it's listed as Cemflo Rendabond or something similar.

Yes, thanks, bought some yesterday, paid Jewson tax on their own brand. The Sika was £37! Even Homebase was only around £20ish, except they didn't have any.

[Skyedriver]

Well I've about a day and a half work left to do, (I'm very slow) and it looks really good, (Wife chuffed).
Need to point up the slabs, 20mm gap, dry sand/cement? I've read some rather critical remarks on PH about all these fancy pointing materials..

Right, it's stopped raining, so better get out there, I've a driveway to dig for the garage before the Type 1 & concrete arrives for the base.

thanks everyone

[dickymint]

Skyedriver said:

Well I've about a day and a half work left to do, (I'm very slow) and it looks really good, (Wife chuffed).
Need to point up the slabs, 20mm gap, dry sand/cement? I've read some rather critical remarks on PH about all these fancy pointing materials..

Right, it's stopped raining, so better get out there, I've a driveway to dig for the garage before the Type 1 & concrete arrives for the base.

thanks everyone

Do not use “dry sand and cement” unless you want to redo it within 3/4 years!

[B17NNS]

Skyedriver said:

Well I've about a day and a half work left to do, (I'm very slow) and it looks really good, (Wife chuffed).
Need to point up the slabs, 20mm gap, dry sand/cement? I've read some rather critical remarks on PH about all these fancy pointing materials..

Pictures man!

Lots of better ways to point than with sand and cement. Again, pavingexpert is your friend.

http://www.pavingexpert.com/jointing08.htm

[Skyedriver]

Pics to follow I promise

Read the paving Expert pages, Jointex seems recommended but I'm rather concerned about not getting it down quick enough and leaving it all over the stonework.

Jewson do a Cementone and a Sika Pave but I can order the Jointex mail order.