Repointing Bath Stone - what mortar?

[goldeagle]

Hi everyone. I have just bought my first home, a Victorian house in Bath. There is lots of work I need to do on the house, one of the first things I want to try and sort is a minor damp problem on some of the internal walls. One of the first things I want to do is repoint the external brick work, as a lot of the mortar is perished and cracked, especially right at ground level (as gas pipe runs right over the mortar line).

I thought getting the wall repointed would be the easiest part, but now I am completely confused by what mortar should be used. Although I am getting someone in to do the work, I want to make sure I understand what needs to be done for a proper job.

The walls of the house are Bath Stone. I have read that a lime based mortar should be used for this type of masonry rather than normal cement, to ensure the mortar is softer than the brickwork and prevent damage. But there seems to be lots of different options - lime mortar, lime putty etc.

I had someone come round to take a look at the work, and when I asked what type of mortar would be used, he said a mix of cement and bath stone sand (sand taken from the quarries after the stone is cut). I mentioned lime, and he then said he could use a lime based mix.

Does anyone have any views on this? Thanks for any advice.

 

[TerenceQ]

Lime based mortar is the one to use.

Can't remember the mix off the top of my head but lime: sand: fine aggregate is the one to use.

Ask around in Bath there is probably a standard mix for that part of the country.