brick pointing advice needed.

[Donno]

Hello all

I have a small job of brick pointing that I have already done, but I did not match the new mortar colour with the old. The house is about 25 years old with dark bricks. The old mortar is slightly yellowish with rather large grains of sand visible. I thought I would just add more sand to the mortar mix I made using concrete and yellowish sand only. The result is a very light grey mortar. Is there anything I can use to colour the mortar that I have already applied. If not I will remove the new and replace it using whatever method is suggested to me. It is not a big job consisting of about 25 bricks on the corner of a long blank wall.

Thanks and regards.

Donno

[Bleedin Thumb]

I'd quess that the original motar was made using off white cement and it sounds like you have used grey cement (assuming you have got the right coloured sand) The sand showing in the original is probably a result of the wall being acid washed (water blasted) after the bricks were layed to cleanthe wall. If you do the same you may get a better match if your sand is the same colour.

[ozwinner]

A picture would help.

Al

[Tools]

you can have the mortar coloured (and they can do bricks too !) by a company called nawkaw.But for such few bricks I would rip it out and do it again.

Tools

[Donno]

Thanks for the response and advice.

You are right in suggesting I used grey cement. I did not think about 'off white' cement as I have not used it before. I guess the off white is better to colour with oxide using a yellow oxide I suppose. If I was to use the grey cement again withe yellow oxide would I get close to the colour I want?

Bleedin Thumb are you saying I should wash the wall first with acid as I have plenty of pool acid in the shed. Will that get rid of the grey look and bring the yellow sand out, or is Tools more to the point by saying I should do it over again - I guess using white sand and yellow oxide.

Ozwinner I will try and get a picture this weekend and post it but I want to try and do something to them this weekend in any case. I am selling the house and want to do it quickly (as usual I hear you say).

Cheers

Donno

[Bleedin Thumb]

Thanks for the response and advice.

If I was to use the grey cement again withe yellow oxide would I get close to the colour I want?

Bleedin Thumb are you saying I should wash the wall first with acid as I have plenty of pool acid in the shed. Will that get rid of the grey look and bring the yellow sand out, or is Tools more to the point by saying I should do it over again - I guess using white sand and yellow oxide.

Cheers

Donno

Hi Donno, I think that by giving you wall an acid wash and high pressure water clean on your new work you will be taking the top layer of the cement from your joint and leaving more sand exposed. This will (hopefully) soften up the look of the new work.
The acid you use is Hydrocloric Acid sorry would'nt know what pool acid is.
Mix it with water 12 parts water , 1 part acid BE CAREFUL use gloves & goggles long sleeves DONT GET IT ON YOUR SKIN OR EYES. Wet your wall down first then brush the acid mix onto the joints and let it stand till it stops bubbling about 3 minutes. Get a guerney and blast away.

It wont be perfect as cement will still be showing on both old & new joints.

As far as ripping it out and redoing without knowing if the original was white sand with yellow oxide ( I doubt it, brickies hate oxide) or yellow sand and off white cement ( more probable) I cant say.
Either way you wiil never get a perfect match.
My suggestion.
1. Try the acid first if your not happy...
2. Experiment making small batches of motar & letteing them dry till you get the best colour or...
3. Pull the whole wall down and redo it or..
4. Render it

[Jacksin]

I watched a mob restore a stone wall where I worked and they used blends of different colour sands to match up the mortar, which looked like a skill that that needed much experience.

[ozwinner]

Its all down to the sand type and colour, washing it with acid will do bugger all, because you will also wash part of the old brickwork down, so you will be back to where you started from.

Al

[Bleedin Thumb]

Yeh you are absolutely right Al.

However if Donna has used the same colour/type sand that was used originally used and has used grey as opposed to off white cement then an acid wash is a cheap way to try and mask the fault.
As I said earlier you will never get a perfect match anyway.... the colours in the quarry change over time and mortar changes with age, hence the range of options I listed. I must also add I'm not a brickie what the hell do I know?? I just like to have an opinion

[ozwinner]

I just like to have an opinion

Yeah me too.

The problem with matching mortar is mainly due to sand colour, thats why its best to see a piccie if possible.

The cement would have probably have been GP ( general purpose) or GB ( general builders), both similar in colour, so the cement wouldnt affect the colour too much.

The sand, the sand.

Al