Rrs93

Cheers. Yes the render basically covered all of the black area and below (I.e. not above the black area). the mystery continues, the mortar is so soil-like if someone told me in isolation to guess what it was, that’s what I’d guess!

This wall is the boundary wall with our neighbours - it’s an external wall on their side but they’ve used it to create a single brick store room on our side. Sorry just noticed your question re. Window - no I doubt this would have been given it was an external boundary wall. neighbours have said it’s not the same on their side but will check further in daylight

Thanks Dave - it is wet. I’ve removed the render and discovered this patch. It’s possibly been trapped behind the render for decades so hoping it can dry out now I’ve removed it. is there anything else you can think of?

Hi all, We inherited a poorly-built single brick garden store built at the back of our Victorian terrace. While removing some of the concrete render (white in the pics attached), I’ve discovered this black mortar which I can only describe as having a soily texture/smell. I’ve taken a wire brush to the area and it is just flaking off (like soil would!!). The black “mortar” does not extend the height of the wall but is rather in a particular spot. This wall is the adjoining garden wall with our neighbours and they don’t have this on their side (albeit they don’t have a bricked structure at all, it’s just garden), so presume it’s a result of our space and the construction thereof. I’ve had limited success on the web and I’m trying to understand what it is, whether it’s a concern and how to deal with it? Ultimately we only really want to board on top to create a utility / gym space so doesn’t have to be perfect, but wouldn’t want to board on top of issues. Cheers