It's "fossil mint" natural sandstone.
We usually paint on a Slurry underneath Indian Sandstone. it helps glue them down and prevent any seep through
You can buy it pre-mixed or make your own using SBR and raw cement.
If you are going to use a jointing compound like Easy-Joint, mix your mortar 6:1, we use a 50/50 mix of sharp/soft sand
Indian sandstone is like a sponge, you may be better sealing the top, as after a few years they look quite dirty, but thats part of their appeal.
Also if possible, widen the path to suit the width of the slabs eg. 900mm or 1200mm, allow for any joints between the slabs
On the pond I had to use a fish safe sealer to stop the staining from below, the rain/pond water and the frost then splitting the slate.
I know enough to know that it needs sealing and a slurry seems the best option. What do people use for the path paving top seal without changing the colours much? (the G4 sealant isn't hardy enough for a footpath and has a strong yellow tint - turning blue slate a greener colour).
The slabs are 3/4 of the thickness of the old slabs so by idea of dry seating them is probably not such a good idea. I'll do it properly, get some MOT down and build a compressed smooth sand layer before putting in the smoother mix for the slates to sit in. I was also going to ask about the joints given they are rough finished.
Find a random slab pattern generator.. Don’t get caught up using too many of the smaller ones in one area. It tends to look too “busy”. Try to avoid repeat patterns close to one another, crosses (four corners meeting) or long straight joint lines. Give yourself some play with your joints. Hire a mixer. £30 a week to save your back and spirit from mixing in a barrow.
What do you mean by "if I do decided to secure them down" ? Are you thinking of laying them on sharp sand? These slabs wont be calibrated. Tou will have trouble if you are going to screed an area then drop these down. They will also move over time and ants love sand under slabs. They'll be all over your glass of G&T come the summer.
I looked for a webpage style generator, but none exist. I may see if I can find a simple Matlab one. I use Mac and most are windows binaries without source code.
I may simply write my own (I can see that a simple random distribution weighting map could be used then iterate with T nodes on a 300x300mm grid, it could also keep a bell shaped gaussian distribution between the junctions by weighting) then release that to GitHub so it's free for anyone.
I was considering initially (before they arrived yesterday) if they need fully securing from the outset however given the underside it looks like they would skate so making the bedding properly seems the only way.
Is that rainbow sandstone or something like it? Pretty soft and porous stone but looks good.
Yes it's natural sandstone so it's very likely to soak through - it arrived with damp through so before I could seal the top it would need to dry out.
Only issue with sealing is most I've seen make some form of colour change. They will change over time anyway and the local environment sees quite a bit of black exhaust soot across the white car so they will need sealing if they're not going to turn too soot-dirty over time. A summer/spring wash each year and a reseal should keep that at bay.
