POSSIBLE CAUSES:
Use of a low-grade, highly pigmented paint.
Use of an interior paint for an outdoor application.
In some instances, paints are formulated to chalk naturally in order to
provide self cleaning properties.
SOLUTION:
First, remove as much of the chalk residue as possible, scrubbing with a stiff bristle brush (or wire brush on masonry) and then rinse thoroughly.
Check for any remaining chalk by running a hand over the surface after it dries. If noticeable chalk is still present use Sandtex Trade Stabilising Solution, then repaint with any of the Sandtex Trade Masonry range. If little or no chalk remains and the old paint is sound, no priming is necessary.
