Sealing natural stone - Preventing staining

[Daijac]

I have looked at your site hoping to find an answer to a potential problem. We have very recently had a new patio laid in natural stone. Just off this new patio we have a garden shed which is painted (also recently) with a coloured preservative. Because of the way the patio is laid I notice that any water running off the sides of the shed, say in driving rain, will drain across one end of the patio. If there is any possibility of wash off the sides this could potentially result in a brown rivulet stain across the patio. The answer is as I see it to use a sealant, but impregnating or penetrating? The resiblock sand stone sealer looks good (expensive but not that much in relation to the cost of the patio). However on your site you recommend leaving treatment for six months plus. If we do one end now and the rest say in six months would we land up with a shade mish mash., or are some of the newer sealants suitable for new lay.

[lutonlagerlout]

speak to lithofin technical help
or visit

sealer info


fixed msh

LLL



Edited By lutonlagerlout on 1248814995

[msh paving]

that link don't work LLL

stay away from resiblock MSH

[Tony McC]

In theory, you can seal a pavement the second it is laid, but I prefer not to do so for various reasons, the most important of which is maintenance. If there are going to be problems with a new pavement, they tend to make themselves known in the first few weeks/months. Rectifying a sealed pavement can be more of a problem than dealing with one that is unsealed. This is probably more relevant to blocks/setts than flags, but the principle remains.

Next, the type of paving material has an effect on the best time to seal. Concrete products can be affected by efflorescence in the early part of their life and some sealants effectively "preserve" the eff in situ, instead of allowing it to escape and/or weather. Conversely, PIC needs to be sealed within days of being laid. However, even non-concrete products can have early-life chemical issues. For example, some imported sandstones are exhibiting problems with cementitious staining, picture framing or variable porosity that can look unsightly. Again, some sealants (not all) have the effect of "pickling in aspic" and make what should be a temporary problem into a longer-term semi- or fully-permanent one.

So: the best time to apply a sealant becomes a judgement call. It may well be that, 4 weeks after installation, all is fine and you can seal away with impunity, and I know there are jobs that have been sealed on completion that have subsequently provided years of trouble-free service. However, if I was to say that every job can be sealed on completion or in the first 3-4 weeks, I'd be inundated with pizdov drive/patio owners who had suffered an adverse reaction.

My list of suggested sealants for various types of paving materials can be found here