Some more artisanal wall resoration

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This does not look good. I'm not a materials expert but it looks like this is a poor match for the rough cast render. My basic understanding is that if you stick two materials together of very different composition then they expand and contract at different rates. Add to this different moisture and vapour permeability and there will inevitably be problems.

It does look like the rendering on our house started to deteriorate after the CWI was installed. To the layman, it seems quite obvious that drilling random holes into your house is a terrible idea.

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