
Remove the paint
Paint should be removed by chemical stripper (such as methylene chloride) and steam or pressured hot water. As the process may be highly toxic, this should be done by a specialist operator.
Other chemicals such as caustic soda or acid, may cause efflorescence* of saturated masonry. Pressure-blasting with sand or other materials is very abrasive and destructive of the masonry surface and risks destroying the tuck pointing* and mortar joints, so it should never be used to remove paint.
OR
Repaint in a more appropriate colour
Subject to a town planning permit, repaint the surface in a colour that matches the natural material (for eg. mid-grey in a flat finish to simulate Portland cement render)
Further information
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