Granite patio

[Nelse]

Hi,
I'm new to this site but finding it a very useful source of information.
I have had a new patio laid with 800 x 200 flags from Nustone in the Blue/Grey granite. Can anyone recommend a sealer for these type of flags and also any suggestions about what to use to point them. They have a 3mm gap between them. Lastly there are a few sand/cement marks on them that I've tried to brush out but they haven't gone completely. Any thoughts on removing them would be much appreciated.
Cheers.

[lutonlagerlout]

800 by 200 ,never seen that size before?
difficult to joint anything at 3mm
thats more a kds joint
hydrochloric acid will remove sand/cement stains ,test on an off cut first and make sure you pre wet the stone before cleaning
LLL

[London Stone Paving]

1. I would be sealing with dryteat stainproof or lithofin stain stop. Nothing else gets anywhere near to those 2 products. Dry treat is 25% more expensive than lithofin but does not need to be re-applied for 15 years if installed properly. Where as lithofin needs re-aplying every 3 approx years.

2. As Luton says, extremely difficult to get any stability into a 3mm joint. I would use an exterior grout gunned in. You will need to make a big effort to get it consolidated into a joint as tight as 3mm and it will be a messy job, so make sure you have a cloth close to hand to wipe up with

3. Lithofin builders clean to remove the cement stains. As luton says pre-wet the stone and take precautions. Follow instructions to the letter on back of the can

Steve

[Nelse]

Thanks for all the advice.
Can you recommend a type of grout to use, and also a gun to do it with?
Maybe I should of had wider joints???

Thanks again.....
Nelse

[London Stone Paving]

Not sure of the top of my head but will find out and come back to you.

[lana]

Guys,
how long should I wait after pointing before I can seal? also, I've read that dry treat should be applied by accredited contractors. can anyone advice me what to expect in terms of approximate costs for dry treating of 14 sq m of granite slabs, please? is it in hundreds or thousands or else?
thanks in advance!

[London Stone Paving]

Guys,
how long should I wait after pointing before I can seal? also, I've read that dry treat should be applied by accredited contractors. can anyone advice me what to expect in terms of approximate costs for dry treating of 14 sq m of granite slabs, please? is it in hundreds or thousands or else?
thanks in advance!

Lana

1. As long as the stone is dry you can point probarbly 24-48 hours after the pointing has been done

2. Granite is dense so you may get away with one litre but will possibly need 2 litres in order to apply 2 adequate coats

3. Cost of drytreat stain proof is approx £44 + VAT per litre.

4. Doesnt have to be installed by an accredited installer. However DT offer a 15 year guarantee and if you want this guarantee it must be installed by an accredited installer.

5. Time wise it shoud take 20 mins per coat

6. Its a job you can do yourself. I can send you an installltion guide if you like

7. One more question, why have you decided to seal?

Steve

[lana]

Steve,
thank you for your answer, most helpful, as usual.
well, to seal or not to seal...good question. My thinking is: being light shade of grey, my slabs might be more vulnerable to staining (leaves, fruits, birds, soles of garden shoes?)
so here is me being "practical" - to seal it safely now to avoid the possible pain of cleaning in a future.
If you think this is an overkill, I would take your advice humbly, I'm no way an experience paver, I've learnt a lot of things I never knew about slabs only because of all these questions transpired when my own patio had been laid. (not sure why it was that I felt the need to know, but there you go and so here I am, asking questions )
thanks again, it's a wonderful place with so helpful people!

[London Stone Paving]

You dont need to rush into sealing. Granite is a very robust material and doesnt stain too easily. Why dont you wait and see how it goes? Waiting a couple of months will not have any negative impact on the paving so its not something you need to rush into.

Also you might experience a slight colour change if you seal which you may or may not like. the impreganting paving sealants like drytreat and lithofin are not supposed to chnage or enhance the colour but with the really dense stones like granite they can slightly darken the colour of the stone.

I'm not trying to sell you any sealant here because its the sort of thing you can buy from anywhere but if you email kayleigh@londonstone.com and ask her to send you a small test sample of sealant FOC and you can then seal an off cut with a couple of coats and see if the colour is affected. I will tell her that you may be in touch

Steve

[Nelse]

Not sure of the top of my head but will find out and come back to you.

Hi Steve,
Did you have any joy with remebering the type of grout and gun to use???

Cheers,
Nelse.

[lana]

Steve,
thanks, I e-mailed for the sample.
now, based on the information from the both "granite threads" here, I'm thinking...what if...it would work better if I:
1. seal with water based sealant
2. do the pointing
3. in a couple of months seal with Dry Treat

*I haven't found any statement saying water based sealant won't work with solvent based sealants*

[Bec@LondonStone]

Hi guys, Steve is off on his holidays this week but hopefully I can help

Nelse - We use Larsen GPM for pointing and have found it to be a good quaity product. Available in a range of colours so it depends whether you want to blend or contrast, but I would recommend the 'Natural' colour which is a mid-light grey. There are other similar pointing products available, we used to stock Easipoint and this was just as good. The gun we stock is the Durgun 45 but, again, there are plenty of guns on the market, some cheap and nasty, some incredibly expensive and built to last.

Lana - The Dry Treat should penetrate a water based sealant but not sure whether a water based sealant will be of any real benefit to you in the meantime. I'll ask our rep from Dry Treat and see what he reckons, this guy knows everything there is to know about sealing so hopefully he will come up with a plan of action.

[Bec@LondonStone]

Quick update for Lana - I've just spoken to Gary from Dry Treat and he says that a water based sealant will not penetrate the stone deep enough to prevent picture framing (grout stains leeching into edges of slabs). I'll PM you his number now, he says that it's a bit technical and so to avoid chinese whispers you're better calling him direct for proper advice. He's lovely, I'm sure he'll be able to help. Let us know how you get on!

[lutonlagerlout]

sorry to stick my oar in, but there aint a cat in hells chance of anyone pointing a 3mm joint with any gun injection system without a god awful mess
even with the metal nozzle 8-10mm is the lowest you can go In my experience
sorry but needs to be said
LLL

[Nelse]

I would use an exterior grout gunned in. You will need to make a big effort to get it consolidated into a joint as tight as 3mm.

Sorry, Have I miss understood. I thought Steve was recommending an exterior grout as opposed to mortar?

Cheers,
Nelse.