Hello,
I'm looking to repoint my 1880s built mid terrace (sheffield) and am struggling to find what to repoint it with. The bricks look like they were originally laid with black ash mortar and most of the house has a thick layer of black coal/ash plaster/render internally as a base coat. Spoken with multiple lime works and online groups, all with differing opinions on what to use. I am not concerned about matching the colour of the mortar to the original at all really, its more that I want to ensure that the new mortar I use is of a suitable consistency for the original black ash mortar. If I use the wrong mix, it could end up being as useless as using sand and cement and spall my bricks further and retain water/moisture more. Somone has tried to repoint with sand and cement at some point in the past and i'm pulling all of that off quite easily as its only about 3-5mm thick.
I change my mind between using NHL or quicklime/putty every time I speak to a different limeworks' advice. although my latest idea was to use LaFarge NHL 3.5 (due to high lime content) with some sharp sand 0-4mm, using a ratio of - 1 : 2.5. Given that its my first time repointing, i've been told that NHL is more forgiving despite being less effective at moisture wicking.
You can see from the photo below however that the original mortar looks like it almost had no sand in it at all, just looks like coal ash dust and quicklime. Does anyone know if my mix of Lafarge 3.5 with sharp sand would be ok to point over the original?
Thanks
![thumbnail_image001.png thumbnail_image001.png](https://www.periodproperty.co.uk/forum/data/attachments/9/9620-b8918576901641ec3fd11e24b6d3e186.jpg)
I'm looking to repoint my 1880s built mid terrace (sheffield) and am struggling to find what to repoint it with. The bricks look like they were originally laid with black ash mortar and most of the house has a thick layer of black coal/ash plaster/render internally as a base coat. Spoken with multiple lime works and online groups, all with differing opinions on what to use. I am not concerned about matching the colour of the mortar to the original at all really, its more that I want to ensure that the new mortar I use is of a suitable consistency for the original black ash mortar. If I use the wrong mix, it could end up being as useless as using sand and cement and spall my bricks further and retain water/moisture more. Somone has tried to repoint with sand and cement at some point in the past and i'm pulling all of that off quite easily as its only about 3-5mm thick.
I change my mind between using NHL or quicklime/putty every time I speak to a different limeworks' advice. although my latest idea was to use LaFarge NHL 3.5 (due to high lime content) with some sharp sand 0-4mm, using a ratio of - 1 : 2.5. Given that its my first time repointing, i've been told that NHL is more forgiving despite being less effective at moisture wicking.
You can see from the photo below however that the original mortar looks like it almost had no sand in it at all, just looks like coal ash dust and quicklime. Does anyone know if my mix of Lafarge 3.5 with sharp sand would be ok to point over the original?
Thanks
![thumbnail_image001.png thumbnail_image001.png](https://www.periodproperty.co.uk/forum/data/attachments/9/9620-b8918576901641ec3fd11e24b6d3e186.jpg)