Which mortar type?

[jigpips]

Hi,
I'm after some advice in regards to mortar type.

My son's house has a damp side wall, from front to rear, which i believe was caused by a poorly laid path.
We think his house was built around 1900, as it has solid brick walls.

Now the course of brick below the blue is in a really poor state, so we plan on replacing this with a second course of blue.

Unfortunately this level will be covered in earth again as the Electric and Gas lines run two brick courses below, but we are hoping to put drainage in.

We've read that it could be lime mortar due to solid brick wall and age of the house, but have also been told to just use a 1:3 mix with cement.
Now my question is, which mortar?

I hope I've explained it well enough to understand.
Thanks

 

[^woody^]

That looks like cement mortar.

Yes 1:3 mix.

 

[jigpips]

Hi, thanks for the reply.

The house has been repointed with a cement mix at some point which you can see in the pic above the DPC, but that is only a few mm deep. It's more like a light skim. There was also some concrete attached to the DPC, which we have knocked off.
The mortar below the repoint is more of a yellowish colour and quite sandy, this is why we were unsure of the mix.


Thanks

 

[^woody^]

Does the ground have sulphates which have affected the mortar, by reacting with the cement? Or just a poor original mix?

Colour, or a granular mix is not indication of lime.

It looks like frost damage.

 

[jigpips]

Sorry, i have no idea about sulphates.

The path was laid towards the house, and those damaged bricks were just below ground, so could have frozen and blown?

Would you still suggest 1:3? would we add any lime?

Thanks again for your replies, i really appreciate the help.

 

[^woody^]

1:3

It looks like typical frost damaged. Replace all the bad bricks.

 

[jigpips]

One last thing, with it being a solid wall, would you dry both inside and out before replacing the bad bricks?
Thanks again

 

[^woody^]

No need to dry the wall

 

[Deleted member 292770]

4:1

 

[jigpips]

Thanks for the info Have made a start on the brickwork, first ever attempt so be kind

Would we use the same mix for the inside too?

Thanks again