Black (?!) Limestone Issues

[jonnybloo]

Hello, I was wondering if anyone can offer any advice please. Before Christmas we had some flags layed at the front to form an additional driveway (the current tarmac drive stayed as is).


We received quotes and looked at other work and settled on a supplier. They had finished another job with the exact limestone we wanted and it looked great. Not jet black but a nice dark grey, we knew it would fade a little and that suited us. This other job hadn’t been sealed as the owner wanted it to fade from black a little.


The supplier also uses Resin based products and explained the benefits in terms of time taken and being able to use it in poorer weather hence it could be done later in the year.


Hindsight is great, and after researching afterwards and finding this forum I now realise black limestone probably isn’t the best! And many people have the same issue. I also believe laying this in poor weather – lots of rain and very cold when the jointing was done, hasn’t helped.


Basically now I need to figure out the best way of restoring the colour and fixing it. It isn’t sealed due to weather so this is a job I will do in the summer (or instruct someone to do).


So the issues I have and need to fix:

1. Sand. There was a lot of sand ingrained on top of the flags, really set into the little grooves and rivets. The fitter has scrubbed by hand and jetwashed them to try and remove the excess sand. To some degree of success with the jetwash but still visible – I can live with this though. Would a steel brush damage limestone? Im assuming so.
   
   
   
   
2. The resin based product has whitened and an almost glue like substance has come off it in places where the jetwash has hit it. I think/hope this could be removed by hand but worries me that the drive can never be jetwashed without the joints leaking. Fixed by sealing? Jetwash hasn’t removed this and you can see it visible in the pic. It could be that the jetwash hit it too soon after it was installed (2 weeks after). You can see on a couple of pics – very white joint and a white substance around the tile edging.
   
   
   
   
3. Colour. This is the main issue. It is very faded and washed out. A light grey. I don’t want a gloss effect but I would like to restore to a dark grey – will sealer do this or does it need colour treatment then sealing ? You can see on the photos where a plank was layed so we could reach the door. It has left a darker stain in a plank shape that the jetwash doesn’t touch. Is that normal? Ive read that they don’t stay black, but the other job we looked at was fine (same supplier, joint material etc).
   
   
   
   
4. Staining – As you can see from the photo there is a long rectangular mark that is like a faded section – where the plank was laid for us to access the house. Jetwashing hasn’t balanced this out. It’s a 2 tone grey – would sealing/colour treatment just leave a darker more prominent 2 tone or an even colour?

I’m assuming this is a combination of several factors: limestone, resin based product, poor weather etc. I’m guessing at few things but really I’m looking for tips on how I can best rectify and make the most of what is there from you, the experts.


If anyone has any experience of resin based products and limestone and what products are best etc then it would really be appreciated


Jon

Though jet black in the crate, they are already grey at fit, i presumed this ws just down to mortar/cement etc

White residue where jetwash has hit the resin based product joints

odd rectangular marking - presumably where plank was for us to reach the door

 

[Bill]

Pavingexpert - The Curse of Black Limestone

 

[jonnybloo]

Cheers Tom, yes ive read that link. Very interesting read. Most people seem to suggest that this occurs after it has aged - mine seems to have been dull, flat since day one.

I looked at some of the recommended products too im just wondering if anyone has experience with resiply and whether a. i can clean off the residue that has "leaked" and b. whether it will have any reaction with said products.

Also, the rectangular stain, whether that will come out with products or whether it will just be enhanced in two tone.

cheers

Jon

 

[Bill]

Cheers Tom, yes ive read that link. Very interesting read. Most people seem to suggest that this occurs after it has aged - mine seems to have been dull, flat since day one.

I looked at some of the recommended products too im just wondering if anyone has experience with resiply and whether a. i can clean off the residue that has "leaked" and b. whether it will have any reaction with said products.

Also, the rectangular stain, whether that will come out with products or whether it will just be enhanced in two tone.

cheers

Jon

It does mention in that link about stains - not just colours enhancers.

 

[Lithofin BOB]

If you want to remove this test a single stone with a suitable stripper , we have lithofin wax off, others avalible. 10-12 min application scrubb with a white pad or stiff brush, rinse and dry to se result. Do not wire brush these flags !!!!!!

 

[jonnybloo]

Thanks for the recommendation, just so I'm clear, is that product purely to clean? Does it seal or enhance? Can it be done any weather? I will wait til we get some dryer weather before sealing I just want to ensure I've done enough beforehand. Thanks again

 

[Lithofin BOB]

We will need to clean the area first, wax off is simply a cleaner/ stripper , or leave the clean ,wait for the good weather your remaining sealer will give some protection over the next couple of months or you can remove now , you will require a dry stone to strip as water will neutralise the product - once fully dry in summer/ spring we can test an impregnating enhancer to get best performance

 

[jonnybloo]

We will need to clean the area first, wax off is simply a cleaner/ stripper , or leave the clean ,wait for the good weather your remaining sealer will give some protection over the next couple of months or you can remove now , you will require a dry stone to strip as water will neutralise the product - once fully dry in summer/ spring we can test an impregnating enhancer to get best performance

Thankyou very much. There is no sealer on at the moment but it sounds like its best to wait until the weather improves and then make a start cleaning and then enhancing/sealing.

 

[Lithofin BOB]

Sorry , I thought you had a sealer to remove, that would be the wax off , come summer wash the area over with a light alkali product to de- grease and then dry,seal. Light alkaline ,we have lithofin power clean ,others similar avalible