Mystic sky limestone help-acid damage!!

taylorc · Post: # 97705Post **taylorc** Sat Apr 26, 2014 10:55 pm

I have just had a new Limestone patio laid by a local company (it's a Digby Stone and the colour is mystic sky), the slabs were laid on MOT type 1 and on the last day the contractor jointed using something similar to geofix (not exactly sure what it was), following this he "cleaned" the slabs using a mild acid based patio cleaner and cold water!!
At the time I was not aware that this is forbidden (I know nothing about landscaping) so I left him to it, however now that the slabs have had chance to dry there is distinct marking and colour discrepancies on the slabs! I have spoken to the company who assure me that they always do this and it has never been a problem but having read the numerous horror stories about black limestone I find this hard to believe!
I will be taking it up further with the company concerned but I would like to know what my options are, from what I have read I am thinking that it may be best to use a good limestone cleaner like LTP Grimex and then leave the slabs to settle for a few weeks before cleaning again and then using LTP Stone Oil to seal/ enhance the colour. Is this viable or is there something else I should consider (falling short of starting again!) ?

I would appreciate any advice as I am starting to panic a bit so thanks in anticipation.......

taylorc · Post: # 97707Post **taylorc** Sat Apr 26, 2014 11:13 pm

Patio Photo

Here is a photo for reference, again many thanks

Sun Apr 27, 2014 12:48 am

acid and alkali do NOT mix
your patio looks not terrible but acid should not have been put near it
LLL

dig dug dan · Post: # 97711Post **dig dug dan** Sun Apr 27, 2014 8:59 am

Looks like its had an effect on whatever the jointing material was used
can roger offer a solution?

RAPressureWashing · Sun Apr 27, 2014 10:04 am

Yet another cock-up, This can be sorted but not with any of the products you have mentioned, basically the surface needs to be restored with the correct Limestone restorer, then sealed with a colour enhancing sealer.
I'm sorry guys if this offends but why do these bloody paving companies insist on using a acid based cleaner when surely any pro installer should know it is a NO way where Limestone is involved

I noticed the OP is in Worcester, bit to far for me to travel, but I do know a company up your way who can sort this, it won't be cheap though.

taylorc · Post: # 97717Post **taylorc** Sun Apr 27, 2014 10:31 am

Thanks for the replies, when you say limestone restorer is there any particular one that you would recommend?

I have read the "cursed black limestone" article and it doesn't really mention any restorers, it just talks about cleaning, enhancing and sealing so that's why I thought I could clean the stone back and then apply some LTP stoneoil (which claims to enhance black stone).

Also, what is the company that you can recommend as depending on what the cost would be I wouldn't mind paying for it to be done professionally (depends on what you mean by "expensive).

Again many thanks

RAPressureWashing · Sun Apr 27, 2014 8:11 pm

The Limestone restorer's we use are not really ideal for diyer's sorry as they are blend of acids, and if you make a mistake, you'd be no better off with the finish then you have now.

Re cost's to "repair" the patio you have , ball-park figure would be Â£20.00 + per square metre.

taylorc · Post: # 97734Post **taylorc** Sun Apr 27, 2014 8:30 pm

Thanks again, as the patio area is roughly 68 square metres then yes it would be expensive!

Can you recommend a good DIY restorer/ cleaner / sealant so that I can at least remove the white dusty residue? I'm willing to live with a little bit of uneven colour but it's the dusty / cloudy look that I can't bear!

Incidentally the contractor is coming out tomorrow to take a look so hopefully he can come up with a suitable solution (at no cost to me)........fingers crossed!

Thanks

RAPressureWashing · Sun Apr 27, 2014 8:57 pm

When you say cloudy, do you mean the lighter marks as in the photo?. What you have to remember is they have etched the surface, with using the wrong type of product, so no amount of cleaning is going to remove this properly.
There are not any DIY products I can recommend sorry, as anything we use is not a DIY product and this sort of work isn't for the faint hearted, as if it goes wrong, it'll look worse.
If you seal over the top of these marks they are still going to be there, so I would advise against sealing this until the surface has been restored to what it should be.
IMO the contractor has cocked up using the wrong products, so any cost's should be his problem not yours.

taylorc · Post: # 97738Post **taylorc** Sun Apr 27, 2014 9:24 pm

I agree totally and I am hoping that he does accept responsibility......my DIY approach is purely a fallback just in case he refuses to accept it!

I will update tomorrow with his response.......

RAPressureWashing · Sun Apr 27, 2014 9:37 pm

Let me know you get on, I'd be interested to know how they are going to "fix" this for you.
Please don't let him fool you with they will "fade in time" speech, they won't.

I'm starting one this week very similar to this, I'll post photos at the end of the week with the finished results.

Good luck tomorrow.

taylorc · Post: # 97741Post **taylorc** Sun Apr 27, 2014 9:41 pm

Thank you

taylorc · Post: # 97751Post **taylorc** Mon Apr 28, 2014 9:03 am

Good new, the contractor has had a look and accepted that it is his responsibility so moving forward he is looking to give it a good clean with a specialist product to remove any soiling and then use a restorer/ enhancer to recover from the damage.
Fingers crossed it is successful.....

RAPressureWashing · Mon Apr 28, 2014 9:29 pm

taylorc wrote:Good new, the contractor has had a look and accepted that it is his responsibility so moving forward he is looking to give it a good clean with a specialist product to remove any soiling and then use a restorer/ enhancer to recover from the damage.
Fingers crossed it is successful.....

That is good news, let us know how is turn's out.
If they tell you what products they are going to use prior to doing the job, feel free to letting me know, and I'll give you an honest answer if they are any good or not.

Post: # 97790Post **Tony McC** Tue Apr 29, 2014 12:42 pm

Moved this thread to put it in the right section for future reference.

The claim that the contractor, who has already effed-up once, is going to "give it a good clean with a specialist product" which remains undeclared, fills me with dread. How would this contractor who wasn't, apparanetly, aware that acid on limestone is a knobby idea, be able to tell what is a suitable specialist product?

I'd want to know what he's planning to use, and a written method statement, before I let the bugger anywhere near the paving again!