The Brew Cabin

Posted: **Tue May 23, 2017 1:59 pm**

Hello,

I laid a riven slate patio over the weekend but have not yet pointed it as I'm waiting for a dye to use in the pointing mortar.

All the slabs have set solid to the full mortar bed but there are a few voids/gaps in the mortar bed that I can see around some of the edges.

If necessary, is there a suitable way to fill in these gaps before pointing? As some of the gaps reach under and beyond the edges I don't think the class II mortar I intend to use will reach (or be 'liquid' enough) and fill all the voids.

Perhaps a runny SBR mixture to flood the gaps?

Any help is much appreciated.

Thanks

Posted: **Tue May 23, 2017 4:13 pm**

Wouldn't bother with dye, it fades quick.
If you point with a mortar gun, you can hold nozzle in void till it spews out

Posted: **Sat May 27, 2017 1:09 pm**

As Sean says, cement dyes fade, and the cheaper ones fade fast. Two-part resin mortars get their colour from the aggregate, so are less prone to fading, and by being a slurry, they will flow into any voids there may be.

SBR mortars are wonderful, but unless you are meticulously thorough with the cleaning, they stain forever.

The simplest option is to use an uncoloured 6:1 mortar based on building sand to flood the voids, scrape out any excess before it cures, and then top-off the joints with your coloured pointing mix.

The Brew Cabin

Best way to fill voids in patio mortar bedding