Grout a sandstone riven slab patio - What product to use? Help

[Jonny Vee]

I Have to grout a patio wich has riven sandstone slab with 10/15mm gap.

I understand dry mix sand cement does not work for this type of slab and brush in product would be ideally. I came across Sika fast fix but load of comments about failure and product coming loose apart to be very expensive for the coverage they do.

Any idea on what product to use which would last and be cost effective?

 

[mrrusty]

I used this successfully https://resiply.co.uk/ https://www.cwberry.com/resiply-resin-based-jointing-compound for some york stone slabs. Coverage on a similar application was about 10sqm/pack - I used £150 worth on 30sqm - of course, it depends how big your slabs are. Went in really easily. You wet the slabs to apply, and after you have brushed it in, you brush off the surplus - tip don't use too much water doing this as it can wash out part of the resin before it sets - I found the first pack stayed soft much longer than I expected, so spoke to their sales team - they said this can happen if you get it too wet washing off. More careful on packs 2 and 3, and it was fine. The first pack did go hard after a little bit.

1 year on, and all is good. I haven't used a pressure washer - only hose and broom so far. I suspect that very aggressive pressure washing could loosen. It's set hard - I would say about the same as lime mortar - hard, but not quite as hard as a strong cement mortar.

I did try dry mix myself first on a small area...and it didn't work.

 

[Jonny Vee]

I used this successfully https://resiply.co.uk/ https://www.cwberry.com/resiply-resin-based-jointing-compound for some york stone slabs. Coverage on a similar application was about 10sqm/pack - I used £150 worth on 30sqm - of course, it depends how big your slabs are. Went in really easily. You wet the slabs to apply, and after you have brushed it in, you brush off the surplus - tip don't use too much water doing this as it can wash out part of the resin before it sets - I found the first pack stayed soft much longer than I expected, so spoke to their sales team - they said this can happen if you get it too wet washing off. More careful on packs 2 and 3, and it was fine. The first pack did go hard after a little bit.

1 year on, and all is good. I haven't used a pressure washer - only hose and broom so far. I suspect that very aggressive pressure washing could loosen. It's set hard - I would say about the same as lime mortar - hard, but not quite as hard as a strong cement mortar.

I did try dry mix myself first on a small area...and it didn't work.

Sound very expensive for a bit of grout. Do we really need a resin joint? what the benefit if you also are worried about jet washing it?

 

[gonch69]

I've used sika fastfix on rivan an smooth which is brushed in then troweled up which is holding up well