Re-Pointing - Help Advice please

[dazzr]

Hello All,
I have just joined this forum looking for advice and help, having searched the web and asked at builders merchants feel more confused than ever.

I am looking to re-point some brick work, the house has Cotswold type stone, the pointing is kind of sand coloured.

I purchased builders sand and mixed with Portland grey cement in ratios of 3/1, 4/1, 5/1 and 6/1 all looked too grey coloured.

One builders merchant mentioned adding colour powder but I thought surely you can get a similar colour without adding powder colours, so I purchased some yellow builders sand. Mixed at same ratios but although lighter still not quite right.

Then today went to another builders merchant who called someone who dealt with Cotswold stone, he advised purchasing White Cement, Hydraulic Lime NHL3.5. He advised mixing at ratio of 1:1:1 meaning 1 sand, 1 Hydraulic lime and 1 white cement. ??

Having looked online I can see no mention of mixing Hydraulic lime with Cement..... That's where I am confused and would appreciate any advice.

Can I mix Hydraulic lime with White Cement and builders sand and any know what the ratio should be? Should I mix 1 White cement, 1 Hydraulic Lime and 2/3/4 or 5 sand?

I also purchased plasticiser and not sure if I should that as well??

Very confused now!!!

Thanks in advance.

Dazzr

 

[^woody^]

Did you buy yellow building sand or red?

Try yellow sand and if still not right add lime, 4:1:½. Lime is a plasticiser.

The colour should be judged when dry, not wet and when applied to the stone, as the drying and the tooling of the joint affects the end colour. And it needs to about three days to dry to its final colour.

 

[stuart45]

You shouldn't use NHL with cement. Use the standard hydrated lime.

 

[dazzr]

Thanks Woody for the reply much appreciated, I have mixed some samples with just yellow sand, white cement and plasticiser. The colour is getting close. Like you say though it seems to take a while to get the final colour.
I have been mixing on clear plastic board, then comparing to the wall. Again like you say I may need to apply to the stone to check colour.
Thanks for your help.

 

[dazzr]

Thanks for the reply stuart45, I thought something may be wrong when googling there was no mention of mixing NHL with cement. Looks like builders merchant was giving wrong advice then.... Have full bag of NHL to use at some point now then...

 

[^woody^]

Have full bag of NHL to use at some point now then...

Put it on the garden. Unless that should be hydrated too.