Page 1 of 1

Getting a Light Coloured Mortar Mix for Slab Pointing

Posted: Wed May 13, 2020 1:01 pm
by OdgeUK
Hi All,

I've recently completed laying a patio with light coloured cast-concrete slabs. These are on mortar bed made up of Cement and Sharp Sand.


Now it comes to the pointing (the gaps are between 6-8mm) I had planned to use a 4:1 Builders Sand / Cement mix, knowing that the Grit Sand / Sharp Sand is really too stony for a good pointing finish.

However, buliders sand is generally yellow and I do not want a yellow / buff finish.


Reading around, one option is an expensive pre-mix compound (want to avoid extra cost) or White Cement + Silver Sand. However on looking up a description of Silver Sand, it says it's basically Grit Sand with the Iron washed out. So this will be just like using Sharp Sand right?

Re: Getting a Light Coloured Mortar Mix for Slab Pointing

Posted: Wed May 13, 2020 10:55 pm
by stoneyboy
Hi odgeuk
If you find sharps too coarse try using plastering sand.
Regards S

Re: Getting a Light Coloured Mortar Mix for Slab Pointing

Posted: Thu May 14, 2020 12:48 pm
by OdgeUK
I've noticed that you can get a "Grey Building Sand" which doesn't cost as much as 'Silver Sand'. Although it doesn't seem to be in stock at the usual places due to C19. I've got a feeling that this will be what I need. Doesn't matter if it's a darker grey than using Silver Sand or White Cement, I just don't want any Yellow / Brown in my pointing as it'll look shite with Light Grey slabs.

Re: Getting a Light Coloured Mortar Mix for Slab Pointing

Posted: Thu May 14, 2020 11:07 pm
by stoneyboy
Hi odgeuk
Plastering sand is sharp so there are no clays to colour it yellow - you'll end up with grey mortar.
Regards S

Re: Getting a Light Coloured Mortar Mix for Slab Pointing

Posted: Tue Jun 09, 2020 9:37 am
by OdgeUK
Thought I'd provide a quick update on this.

Due to the pandemic, any sort of Silver / Grey Builders or Plastering Sand has been out of stock.

A friend had some, quite yellow, bags of regular building sand and a test mix at 1:4 showed this to be (as expected) very sandy coloured.

Feeling desperate, I took a load of the leftover Sharp/Grit sand that I'd been using for my Mortar bed, and sieved it with a regular baking sieve from the kitchen! This took all the larger stones / ballast / grit from it and left me with a nice light coloured sand mix. Did a 1:4 with this..and voila!! Nice cement coloured mix when dry.