Cleaning sandstone paving

[Damian_30]

Hi,

Laid some pennant sandstone paving last October and jointed with Romex D1.

As there was some resin residue left on some of the flags, I thought I would leave it the winter to clear and then seal with Stainstop in the spring. As you would expect, the flags have now got a bit of algae and dirt on them which I can't seem to shift with hot soapy water and a bit of elbow grease.

Any other ideas for what I could try - didn't really want to chance a normal pressure washer with sandstone being quite soft.

Many thanks as ever,

Damian

[Tony McC]

Pennant sandstone is not soft! As sandstones go, it's pretty bloody hard, and should be more than capable of withstanding the occasional pressure washer.

Full info on cleaning paving can be found on the main website

[Damian_30]

Thanks Tony...

I guess I should have looked through the site more carefully before posting.

I think I was concerned about blasting away the diamond sawn edges with the pressure washer. I think I will have another go with the hot soappy water, once over with some clean bleach and then a careful pressure wash.

If that all works I will get some stainstop on asap!

Thanks again,

Damian

[mickavalon]

sounds a bit girly but try a scouring pad with a bit of fairy liquid, rub it over a bit that's not too prominant first, but as Tony said, it should take a pressure washer, just keep it angled and away from the joints

[RAPressureWashing]

Damian
We pressure wash for a living so done properly there would be no damage to pointing or the surface. From your profile you are outside of our area really, but if you want the name of a pro-company near you let me know.

[worldofpaving]

Household bleach is often good at removing algae but be careful - try it diluted say 1 :5 with warm water, preferably a little test spot as much out of view as possible then let it dry. if there is a difference and no undesirable effects, either carry on or, if no change, repeat the exercise and the concentration until you get some result.

Combined with the pressure washer, this should work.

Best,
WOP

[RAPressureWashing]

Household bleach is often good at removing algae but be careful - try it diluted say 1 :5 with warm water, preferably a little test spot as much out of view as possible then let it dry. if there is a difference and no undesirable effects, either carry on or, if no change, repeat the exercise and the concentration until you get some result.

Combined with the pressure washer, this should work.

Best,
WOP

WOP
You are really not telling anybody anything that can't be found on the main site and with better/proper instructions, as in PPE when using any chemical, damper surface first etc. plus it's not always wise to let some chemicals dry out on certain surfaces.
Sorry but this is an open forum, and a little knowledge in the wrong hands can lead to dissapointing results.

[msh paving]

Thanks for that R&A ,as you say a little knowledge in wrong hands can lead to larger problems,
please don't post misleading info WOP thx MSH

[Damian_30]

All,

Thanks for the comments - I will probably have another go with the scrubbing brush but I'm not holding out too much hope.

Roger - I would be interested if you can recommend anyone covering my area (Coventry) as it would be worth paying to get it back to new for some stainstop.

Thanks,

Damian

[RAPressureWashing]

Damian,
You should have a pm.

[Damian_30]

Hi,

Thanks all for the replies and thanks Roger for the PM.

Before I call the professionals in I thought I would have one more go at trying to cleaning the paving up and managed to borrow a pressure washer at the weekend.

I've been reasonably successful but I've not managed to get the paving totally clean yet (a bit two tone in places). In particular, there are still some residue marks left over from when I used the Romex D1 to do the jointing. The instructions did say that this might happen but any ideas on how I may be able to get rid of the marks?

I'm thinking of getting a hand scrubbing brush and going over each flag again with soapy water to see if I can get an improvement. Apart from getting someone in with a more advanced pressure washer, does anyone have any other thoughts on cleaning and the Romex marks in particular?

Thinking about is I should have perhaps used a basic water based sealer before I used the Romex to give a bit more protection.

Any further thoughts greatly appreciated.

Many thanks,

Damian

[Tony McC]

The Romex residue will weather off in a few weeks - it's designed to do so, then they can sell you a sealant as well!

[Damian_30]

Hi Tony,

Would be great if the sealer was to weather off in a few weeks but I used the Romex 6 months ago and it is still no different.

Perhaps I didn't do a very good job using the Romex but now the nice clean light blue colour of the pennant stone is now a two tone mix now I've cleaned all the algae and dirt off.

I guess there is not a lot I can do but hope that it goes over the next year or so but would it be worth still sealing the stone in the meantime (or will sealing the stone seal in the resin marks?). Apologies for what probably seems a daft question.

Thanks,

Damian

[Tony McC]

There is a solvent that can be used to clean off Romex that has been allowed to 'set' on the surface of paving.

I'm guessing that, if the resin film is still there after 6 months, then too much was left on the surface. We jointed the Celtic Knot just three weeks back and there's not a trace of the film residue left behind.

If you call Rompox Ray [07872 824010] after the bank holiday, he'll be able to tell you how to get hold of the cleaning solvent.

[worldofpaving]

Hmmm, R&A, MSH, this is not misleading info, I have used bleach myself succesfully in the past for this purpose.

As for PPE, my wife uses bleach quite regularly around the house and observes the basic instructions given on the bottle.

All of the people will not agree with all of the things that are posted all of the time but when an attempt is made to help someone I don't believe that your comments are helpful or constructive.

It goes without saying that the best and wisest course will always be to get a professional in to deal with the problem but there is a cost attached which many people are reluctant to pay.

My apologies for not having scoured the main site before posting, I did not realise that this was a pre-requisite for trying to help someone.

WOP