Jointing indian sandstone - cement stained 'border - Advice sought

[JohnEB]

Following the great advice and guidance on this site, we've nearly completed laying a large patio of Indian Sandstone. We opted to use an almost dry mortar mix for jointing, but until we got the hang of it, we got a cement stain along the edges of some of the joints.

I've read the dire warnings against using brick acid to clean this off, so have researched alternatives and have found Geocel EcoChem Brick and Mortar cleaner, which appears to be suitable.

I'd be very grateful for experienced opinions on this product and any possible alternatives. I am planning on trying a straightforward jet wash tomorrow, but not holding my breath. Also considering a sandblasting attachment for the jet washer. Or maybe the winter weather will be enough to erode/fade the marks?

Any advice greatly appreciated

[Tony McC]

I've never used the GeoCel EcoChem myself, and I've not heard any favourable comments, either. Most are along the lines of "It dun't bloody work!"

I have it on my To Do whiteboard over my desk as a product to try out but it's been such a hectic year, I've just never had the chance.

We'd be very interested to hear how you get on, if you do decide to give it a go - before and after photies are ideal!

However, I'd be sorely tempted to leave the paving over the winter to see how it looks come the Spring.

[RAPressureWashing]

I would be very careful of using anything at the moment even a jet washer, as you say "Nearly Completed" so the pointing won't have had time to cure/dry completely yet and there is a chance you could dislodge the pointing working that close to the joins, as Tony stated if you can leave it to over winter and see how it look's if it is just mortar stains/smears this can be easily got off, just not yet as the pointing is to new IMO

[JohnEB]

Many thanks for your replies, Tony & Roger.

I think I'll leave it to see if the winter weather does the trick. I'd hate to spoil the patio now - it's taken my wife (flag chooser/concrete mixer/pattern advisor/boss) and me half the summer and all autumn to lay it!

[JohnEB]

A very belated update!

Following Tony and Roger's advice, I decided to leave the cement stains and, sure enough, the winter weather shifted them nicely. After one winter they were nearly gone, after two, it almost looked professional!

Many thanks again for your advice and the website as a whole. The information given has helped us to achieve a patio we're very happy with, and avoid such pitfalls as a self-styled expert odd-job man friend (now known privately as 'Mr Blobby'), who was very insistent we should throw down our sandstone slabs on five blobs of building sand mortar!

[Tony McC]

Happy it worked out for you....and reassuring to hear that our advice is actually valid.....at least some of the time!