Damp problems after injected damp course

[garlicbread22]

Hello,

I live in a victorian terraced house of brick construction. I renovated the house in 2014 which included installing an injected damp course and re-plastering. The damp course has been largely effective, with the exception of an area in the back corner of the house adjacent to the neighbouring property. In this area there is also an exterior door and also the boundary garden wall adjoins the property. When the damp course was installed he also went up and around where the garden wall adjoins the house.

The damp goes quite high, up to about 1.8m, and I get readings between 20% and 30% on my damp meter. The interior paint is coming away very badly and seems to be getting worse over time (been trying to ignore the problem!).

About 2 years ago I hacked off the bottom of the exterior render where the damp area is but this doesnt seem to have helped.

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Webp.net-resizeimage.jpg (143.77 KiB) Viewed 1078 times

I am going to get in contact with the contractor as its covered by sovereign guarantee, but would like to be more informed before doing so. What are peoples thoughts on the damp problem and what could be causing it? Do you think it could be linked with the garden wall?

Thanks in advance

[toolbox]

Yes the garden wall almost certainly bridges the DPC you may also have condensation in the corner due to poor air flow with the drawer unit in place.