Washing flags half way through

[Rolyan]

We have started laying Marshalls Chancery flags (cast concrete) but the English weather has caught us up. It's rained on and off during the laying (2 days now). We are laying them onto a semi-dry mix of 8:1.

Question: some of the mix has got onto the flags. Not a lot, but a bit trodden on when we stand on them checking for rocking, etc. Should we leave it to dry (ha!) then brush it off with a dry brush. Or hose it down now. Or brush it down now using a brush and a bucket of water.

Any advice would be appreciated, particularly a response now if we need to act quickly.

Many thanks in advance.

[Tony McC]

Well, my response is delayed due to Mrs Taz pulling a sickie since Easter, so you may have solved the problem and moved on by now.

Using acid-based cleaners on these flags is to be avoided at all costs. immediate remedial action is best - in damp or overcast weather, wash off any cementitious stains with clean water as soon as they are spotted and try to avoid excessive trafficking from bed to flags. in hot or sunny weather, any light 'tread' staining tends to dry out rapidly and allows the stain to be dusted off with a brush.

A handy trick to use when laying expensive flags on cementitious bed is to have a length of hessian sacking, or even a small sheet of visqueen, a ripped-open sand bag or an offcut from an old Agg Bag, and stand on that when checking the flags for rocking moment. Keep the staining off the flags if at all possible.

[Rolyan]

Many thanks for your response, and I hope everyone is now okay. The staining (more dust really) dried out in the sun (ha!). We only had a little, but enough to dry it, so we just brushed it off as you said.