Late Victorian semi-detached sandstone house. The render on the gable has had numerous repairs over the years. I believe but do not know for certain that the original render was lime and some of the repairs were concrete.This has been over-rendered in concrete with two vertical and two horizontal expansion joints on the gable and angle formers on the corners.
Deep cracks have formed around the expansion joints, angle formers and also in the over-render around the windows. These are letting water into the house walls.
There is also a gap between the bottom of under-render and the concrete path that runs alongside the gable that is funnelling water into the cellar.
I need to get quotes to sort out the render. Does the over-render need to be removed and the house fully re-rendered or should it be sufficient to chisel out and fill the cracks in the over-render?
If this needs to be re-rendered is concrete ok or does it need to be lime render?