To seal or not to seal??? - Slate paving slabs

[MattyH]

Hello all. Just signed up to the website tonight as I'm looking for some advice......

I am currently laying a large amount of slate paving slabs for a customer who has now started asking questions about sealing them. I have never done this before with any slabs I have laid and wonder if it's worth it or not?????

I assume they need to be completely dry before doing so (which could be difficult at this time of year!!), should it be done before or after pointing? or both? Although my pointing is tidy, as I've never laid slate before, I'm worried that they'll stain even if I use a really dry mix...

Is there any real benefit to sealing slate other than the aesthetic 'wet look' it can give the area which some people like..... from what I've heard it sounds like a lot of hassle for not much reward.... so please help!!

Cheers,

Matt

[lutonlagerlout]

I laid some trustone slate the pther week matt and it is tricky to point,need to be very careful and watch the weather

as for sealing its too early yet,need 4-5 days of warm dry weather so march april maybe
www.extensive.co.uk do a good range of sealers but IMHO its not really necessary unless the client wants that glossy look,that will have to be redone every couple of years
LLL

[Stumpyclifford]

Smartseal guy does not recommend sealing a non porous/dense paving as it just sits on top without being absorbed therefore wearing out pretty quick, don't now wether I should or not, but I use WD40 on my slate front doorstep, and no its not slippery, wipe on wax off, Grasshopper

Regards
cliff

[jonnyboyentire]

Let me check my sealant for slate, it has a much smaller molecular density than most others.

[MattyH]

Thanks for the feedback. My main concern is staining the slabs when pointing. The customer also wants to add a dye to the mix to darken the mortar joints..... does anyone know if this just adds to the risk off dis-colouring them when pointing? The joints are quite tight so it's already going to be tricky!!!

[GB_Groundworks]

Use a polymeric jointing compound such as romex basalt or gtfk etc

[London Stone Paving]

Clients often think that natural stone needs to be sealed. A lot of the time it doesn't.

The colour of slate is quite rich and glossy anyway, so sealing it to enhance the colour should only be done if the client REALLY wants it look shiny.

Slate is also a tough, dense material so unless the circumstances are exceptional it does not need to be sealed for protection either. Find out the reasons why the customer wants to seal and give them the correct advice.

I would stay away from dyes, there are much better products on the market as Giles has already said. Easipoint is also worth a look.

[MattyH]

Ok will do! Thanks a lot for all advice.

[Rose L]

Despite its reputation for being hard, some slate marks/scratches really easily (like a blackboard...) Try scratching a sample with a nail. I have some which even gets marked by brushing with a yard brush. Thinking of trying sealant when the weather warms up to stop this as it looks a mess most of the time!

[lutonlagerlout]

well said rose,but we have to remember that even the hardest stones/woods will mark/scratch
I have oak floors at home and they mark real easy
nothing is unmarkable
LLL