DIY Doctor UK DIY Forums

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?

Hi odgeuk
If you find sharps too coarse try using plastering sand.
Regards S

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.

Hi odgeuk
Plastering sand is sharp so there are no clays to colour it yellow - you'll end up with grey mortar.
Regards S

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.