Colouring/staining existing concrete slabs

[Ash]

Anybody know of any resources describing techniques for colouring or staining an area of existing concrete slabs? The slabs are cheap (no-name) concrete, various sizes with a Yorkstone textured surface. They are 'natural concrete' coloured and as such way too bright under direct sunlight. We need an easy (and preferably cheap) way to colour or stain them as replacing them is not an option. Area is about 50 sq m.

Thanks for any help.

[mouldmaker]

The brief answer is there is no way.

If you can't replace them, try getting them dirty - accelerating the weathering effect. Horse manure will help.

[Tony McC]

There is a product that is sold in some parts that is said to "re-colour" existing concrete. It can only make a pink-ish flag a bit redder, or a light buff flag more yellowy-brown, but it cannopt turn, say, buff into red or vice versa.

It's not cheap and it's not paricularly good, either. I've seen it used on so-called 'makeovers', including one done for a telly program, and it would have been cheaper to buy new flags! I've not seen it around since 2000, possibly 2001, so it may not be available any longer. It was manufactured in Germany and had a strange name - Beton-kleur or summat like that.

Acids are sometimes used to 're-colour' concrete, but again, they are expensive, unpredictable and hardly worth the effort.

As MM said, get them mucky or paint them with a dark masonry paint.

[Ash]

Thanks to both of you. Looks like we will have to wait for nature to take it's course.

I need a new pair of sunglasses anyway