Pointing, mortar colour & aesthetics

[Jimmy Conway]

Don't imagine there's a definitive right or wrong for this but wondered what you experts thought about pointing Indian sandstone slabs.

Should the mortar pointing be a colour that is subtle and blends in with colours of slabs or should you try make a contrasting colour?

I'm concious of using a contrasting colour as it could highlight any slabs slightly out of alignment, joint widths etc.

Slabs are mostly grey/pink/peach.

Has anyone tried experimenting with different colour cement ie, snowcrete the white cement and different colour sands to make different colours or do you guys just use on site sand and cement and not worry too much about colours?

Have seen plastering sand mentioned for pointing, what's the benefits of plastering sand?

Thanks

[mike builder/landscaper]

Yes, I use a little cup full of brown powder mortar tone to the mix (3-1 plastering sand/ Portland cement) works a treat and looks good. Portland cement is 100 per cent cement if you didn't know that, not the general purpose multi cem.

[Jimmy Conway]

Thanks mike.

Dumb question time - if go to supplier and ask for bag of cement they give me OPC, is OPC different to Portland cement that you say is 100% cement?

My understanding of sand -

Building sand - for workability and better finished look
Sharp sand - for larger joints, structurally stronger but might look rough
Plastering sand - ???? Best of both worlds but more expensive??


Thanks

[mike builder/landscaper]

You might have to order the Portland in at your local bm, I use it for brickwork up to dpc, chimney stacks and ridge tiles, all exposed areas really, they always keep a pallet in for me. And yes washed plastering sand is the best of both worlds.

[lutonlagerlout]

what we get mugged with in the merchants is CEM2 which is a mixture of PFA and ggbs and cement
in fact i believe it is around 65% real cement and the rest is additive

Cem1 is 100% portland cement where strength really matters,but it can come out very grey

cheers LLL

[lemoncurd1702]

OPC and building sand is fine and the natural colour of this mix will look fine with your paving.
Trying to dye a mix the same colour as your slabs WILL result in a mismatch which may look worse than contrasting with a subdued colour.

[KLS]

If you did want something different try a colourd pointing mix such as larson that London stone do or their gtfk (I think that's the right letters I the right order) they are pre batched so are a constant colour.

Contrast v complimentary we have done both depends on the client/stone. Usually though a buff colour is chosen. But we have done a contemporary gray, really quite light, patio with 5mm joints pointed in black.
If you look at my Facebook site you should see some images of both types of pointing.

[sy76uk]

I use all three types of sand in my pointing mix some times with white cement. Makes a peachy colour mortar that is lovely to work with. Especially if you use red building sand.

[Jimmy Conway]

Thanks for replys, slab area is replacing lawn that four legged friend has destroyed with bitch urine, hence slab area is going to be her wee-wee area, and to keep it clean will get pressure washed and hosed down regularly, that's shy I want supper strong pointing.

I'm trying to save the pennies where possible so wo't buy the top dollar jointing compounds.

Would a 3/1 pointing mix of

Plastering sand
Cement (the fancy 100% cem 1 that's been mentioned)
Plus SBR
Would it be worth adding lime to make it less brittle?

be needed to withstand pressure washing or does this Sind kike mental overkill ?
Would it be worth adding lime?

Cheers

[lemoncurd1702]

Sand, building or plastering,(personally softer sand gives a smoother joint) whatever is readily available. SBR, why? Are the bricks your house built with stuck with sbr? No.
3/1 great, a bit of plasticiser or lime makes it easier to use.