The Brew Cabin

Posted: **Sun Apr 17, 2005 12:19 pm**

The patio is laid, and we are just waiting for the rain to stop belting down, before I point.

The trouble is, "She who must be obeyed" has instructed me that the colour and quality of the pointing has to be correct...first time...no excuses. I've extremely limited experience or skill in this, so I thought I would try a mix that gave a greyish colour (ready mix from B&Q) in a small area first, so that she could review it.

She has done, and it's too brown! However, it's not dried out yet, so it may go greyer (we used it on a little wall last year, and that went grey, which is why I tried it).

Couple of basic questions from a beginner in trouble...

1) If it DOES go greyer, will it then stay that way, or go back to brown every time it rains.

2) If it DOESN'T go greyer, how can I adjust it.

3) We are doing it as a dry mix, brushed in then wetted and struck, 'cos I dont trust myself to point using a mortar without staining. Is the colour affected by whether it is initially pointed wet or dry.

Many thanks for your assistance and a great site.

Posted: **Mon Apr 18, 2005 6:17 pm**

All mortars exhibit a change in tone or shade when wet, unless they are jet black, so your plan to have mortar on a consistent colour regardless of weather is doomed to failure unless you choose one of the sprecialist polymeric products.

Using the pre-mix mortars, you'll struggle to change the final colouring from browny to greyey. The sand and any added pigment determine the colour of a cured mortar, so to convert a browny mortar, you'd need to add a grey or silvery sand and/or add pigment. As all the various pre-mix products use different sands and pigments (along with othre additives) I can't give a fail-safe recipe for changing the colour that will work with all products. It's trial and error, I'm afraid.

The final colour of a mortar is affected by how the mortar is prepared. You get much better pigment dispersal and colour development in a 'wet' mortar than you would with a dry brush-in mix that is surface-wetted. The difference can be quite stricking!

Posted: **Wed Apr 20, 2005 12:14 pm**

Tony - many thanks for your assistance. If I talk to "She Who Must Be Obeyed" I will sound as if I know what I'm talking about. Thats not a bad start.

I think I may have to make my own mix, and adjust it accordingly. Nearly there now, but it's rained for something like forty days and forty nights...nice patio, we just can't use it.

Thanks again.

Posted: **Thu Apr 21, 2005 9:21 pm**

Nearly there now, but it's rained for something like forty days and forty nights...nice patio, we just can't use it.

Well... at least that's better than some <spit> decking that you just can't use

Good luck with the pointing!

The Brew Cabin

Driven mad by grouting - She's very demanding on quality!