Indian Sandstone White Stains


Postby gratian » Mon Sep 22, 2008 12:36 pm

I have recently had my patio laid with Indian sandstone. The stone looks great and the guy who laid it was professional and maticulous in his work so I guess this is not his fault, if indeed there is a fault at all.

A lot of the slabs now have white stains around the adges and one stone particular has gone almost completely white. The stones are surrounded by bricks and a lot of these have gone white too. The stains disappear when it rains or has water thrown on them but they re-appear when the slabs dry out. I read somewhere that it is salt and is quite normal for it to happen but I need to know if I need to do anything.

Any help would be greatly appreciated. I can send photos to anyone who would like to help me out (of the slabs that is!)
gratian
Rank: Labourer
Progress to next rank:
0%
Posts: 1
Joined: Mon Sep 22, 2008 12:28 pm

Sponsor

Simply Build It

Postby TheDoctor4 » Mon Sep 22, 2008 3:24 pm

Hi

This sounds like Efflorescence. If you have a look at the DIY Doctor project relating to this it may provide you with a little more information: http://www.diydoctor.org.uk/projects/efflorescence.htm

Regards
TheDoctor4
Rank: Project Manager
Posts: 16777215
Joined: Tue Jul 24, 2007 9:12 am
Location: Somerset in the UK in Shepton mallet

Postby Annie71 » Sun Jul 03, 2016 1:18 pm

PLEASE HELP ...did you have any success with the salt marks on your indian stone flags?? We have recently had a large area laid and after 2 or 3 months it is now covered in this white salt and looks very unsightly. We have tried everything to get rid of it, so any ideas would be greatly appreciated.
Annie71
Rank: Labourer
Progress to next rank:
25%
Posts: 2
Joined: Sun Jul 03, 2016 1:08 pm

Postby Annie71 » Mon Jul 04, 2016 3:09 pm

Hi, so I'm assuming that once we have these Indian Stone flags covered in white salt, there is really no way to get rid of it and we have to live with it for what could be years until it eventually goes?
Thanks
Anne
Annie71
Rank: Labourer
Progress to next rank:
25%
Posts: 2
Joined: Sun Jul 03, 2016 1:08 pm

Postby thedoctor » Mon Jul 04, 2016 6:06 pm

Hi,

The powder you can see on teh surface is called Efflorescence as stated in the post below. You can find out more about it here. If you have a look at the DIY Doctor project relating to efflorescence, it may provide you with a little more information: http://www.diydoctor.org.uk/projects/efflorescence.htm

Essentially all stone/masonry etc is made up of minerals and salts from the earth. It also has both a moisture content. Some of the salts are water soluable and, while the water is in the stone (more after heavy rain etc) the salts dissolve. When it stops raining, the water in the material tries to escape to the surface where it evapourates. As it travels to the surface it brings the soluable salts with it. It evapourates on teh surface of the wall or patio and leaves the salts behind. This is what you can see.

On a very dry day, you can brush these salts off. Sometimes it takes a good brushing with a "SOFT" wire brush "CAREFULLY" to remove them. Then, to avoid the situation occurring again, it is a good idea to seal the surface of the stone/masonry etc.

The best stuff for sealing Indian Sandstone is (believe it or not) Indian Sandstone Sealer !! You can find out more about this by watching the video at this link where you can even buy the stuff.

Be aware that it is NEVER the case that a slab or brick or block etc will be entirely free of water. They absorb it from the air, the ground, spilt drinks etc. Treating with a sealer does not guarantee a salts free surface but it will reduce the efflorescence by at least 85% if applied properly.
Good luck

http://www.diydoctor.org.uk/DIY-superst ... litre.html
thedoctor
Posts: 2454
Joined: Sat Apr 08, 2006 12:15 pm

Postby hop3y » Wed Aug 17, 2016 1:42 pm

Great reply -

Sorry to hijack the thread, just had an Indian Stone patio laid myself. Looking at sealers and see that this one comes well recommended. The patio was laid 2 weeks ago. How long would you recommend it resting before I seal it? (Eager to get it sealed before anything is spilled on it!
hop3y
Rank: Labourer
Progress to next rank:
0%
Posts: 1
Joined: Wed Aug 17, 2016 1:36 pm

Display posts from previous
Sort by
Order by



  • DIY How to Project Guides

  • DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!



 


  • Related Topics