Advise on silver grey granite - Think i have damaged my slabs

[J4ckc]

I recent layed my patio myself. After a lot of research on here and other sites. I have dark mark around the edges of some of my slab. From the sand and cement. Iv tried scrubbing them with warm soppy water, clean water, patio cleaner. I thinking of using acid to see if I can get these marks of. But I don’t want to damage the slabs. This bring me to my second problem. I also use a pressure washer to see if I could get the marks off and now the most of my slabs have gone dark. I’m wondering if i have etched them and damaged them.

[alrat]

Have you sealed and jointed the patio yet? If so what did you use in the joints? Did you use an SBR slurry on the back of each slab and keep each slab surface and sides clean during their installation?

Marks round the edge of the slabs are usually caused by the jointing mortar/compound being drawn in to the porous slab. It's hard to tell without a picture and more detail.

I can tell you that granite is highly resistant to acid, so it's usually safe to use an acid based cleaner, as long as you test an area first. I recently used Lithofin Builders Clean, it's acid based. It didn't cause any problems for my Silver Granite, but equally didn't seem to clean that well. I was only removing some ingrained stains from bird poo etc, not the problem you have.

[J4ckc]

Thanks for the reply. I feel like I'm at a lose end.think I have ruined the patio before its finished. I use a sbr slurry on the back of the slabs and layed them on a full sand and cement bed. I havnt sealed the slab yet because of the mark. And I have used silka pave fast fix grout. The Mark's was on the slabs before I grouted. I used mortar and brick cleaner on a small patch today and I think it has done the trick. But I still have the problem with the discolouring on the slabs. And it's only happened since jetwashing them. Could jet washing damage granite? I'm trying to upload some pic but it's not letting me. I need a url to upload them

[J4ckc]

https://ibb.co/WV3fbh9My Webpage

[J4ckc]

Another pic

Some of the have dirt marks on from footprints. Most of them are a lot darker. They are the ones I have jet-washed. Do you think they will stay that way now?

[Tony McC]

I can't see any real problem there - I think the residual moisture needs time to dry out and, if you must use a sealant (Why? For God's sake!) then the paving has to be abso-bloody-lutely bone dry or it will go wrong - Sealants Gone Bad

The Sika Pave-Fix is, with the dishonourable exception of Geo-Fix, one of the worst imaginable products for jointing. It has no redeeming features whatsoever.

[J4ckc]

It's been about 3days now and if only seen the slightest difference in a handful of slabs. So you think I they will go back to the original colour? I agree I messed up with the grout. A friend recommended it and I read some reviews online that said it was good. Now it's down I don't like it. What grout do you recommend? Don't you think I should seal it?

[mistajay]

I use this and it’s real good, tip: keep the slabs real wet as this product will not set if wet, you can even store unused material in the tub submerged in water https://www.amazon.co.uk/Jointin....0V0U5MG

[Tony McC]

That's another one-part polymeric, MistaJay, so not something I could recommend.

I seem to be repetaing this quite a lot over the last 18 months or so: if you want to use a resin mortar, choose a good quality 2-part resin, one that actually bonds to the paving. They cost a bit more, but the performance is light years ahead of even the best one-part product.

[J4ckc]

I don’t mind paying abit more for something that’s good to work better. Quality over quantity. Do you have any brands your recommend?
I still haven’t seen much improvement in the colour of the slabs. Do you know of anyway I could get them back to the original colour? As I’m expectig rain over the next day or two and if it is down to them drying out I don’t want the rain to make the problem worse

[alrat]

Tony I completely agree with the two part resin being far better than a one part polymeric, but you have to consider the DIYer too. Working alone without the experience you guys have, the speed these two par resin products go off makes it difficult to use and puts many a DIYer off, we're not capable of working at the speeds required. Especially on silver granite when you have to make sure you get all the jointing compound off the slab before it dries.

For a low traffic home patio, is a one part polymeric with a good reputation, such as Easyjoint, really the end of the world? At least it allows a DIY user to take their time, potentially leading to a better overall result (less likely to mess up), even if not as likely to last as long.

For my Silver granite I'm considering Easyjoint for this very reason. With the extra time before it goes off, I could take my time and just feed it carefully on to the joints, with little risk to staining the slab surface. It would also allow me to but a pack and use just a little bit to test it on one slab to ensure compatibility, with a two part once mixed it's got to be used. Pros and cons I suppose.

[J4ckc]

Tbh I couldn't fault silka brand it has hardened well and very easy to install. Only downside is the colour. I was expecting grey. But it's more like a sandy grey.

Going back to my first problem. It been over a week now and the slabs have not dried out. Does anyone have any sulution on getting them back to the original colour or have I messed them up now
I went round the other day with brick and mortar cleaner to clean off all the marks and the mojority come off. I can't seem to get them 100% clean. Getting on my t**ts lol.

[Tony McC]

It can take weeks, months even, for paving to properly dry out, depending on the site location and the method and materials used in construction. No matter how stressed you may be, it will NOT happen overnight.


Alrat - I've worked with professionals, DIYers, handymen and the terminally incompetent when using a 2-part, and as long as they are following instruction, there has never been a problem with timing or ease of use. The only time I see or hear of difficulties is when there has been too little water used during installation.....usually because they either "know it all" or haven't bothered reading/viewing the guidance.

There is no technical reason why a good 2-part should be any more difficult to install than a typical 1-part polymeric. The working life of a properly prepared 2-part should be in the 20-30 minutes region, and, to be honest, if even the most cack-handed DIYer can't sweep in a slurry mortar over 12-18m² of flagstone paving in half an hour, then they really oughtn't be allowed out of the house!

[J4ckc]

Just an update. It’s been over a month. And there has been no change what so ever
I’m thinking of putting. Wet look sealer on it. Because when it’s wet you can’t notice it. Do you like that is a good idea?

[Tony McC]

Sealants often preserve aesthetic problems rather than solving them.

If you really want to consider a sealant, choose a flag that is displaying p[retty bad markings and apply the sealant to that flag alone. Leave it for a nweek and see if it's has actually helped.

If it's done buggerall, then it's no big task to hoick out the sealed flag and replace it; if it's made a marked improvement (no pun intended) then get the jollop back out of the shed and seal the rest!