"NY" wrote in message
...
Our house is brick built, with mortar rendering over this. The mortar has
been painted with white paint - I can't tell whether it's plain paint or
whether it has sand in it to give it a texture. That was done by the
previous owners before we bought the house two years ago.

Large areas (patches of several square feet) of the paint has suddenly
started flaking off the mortar - it seemed to begin at the same time (late
last year / early this year) in various parts of the wall. The flakes are
several inches square and quite thick as if many coats of paint had been
applied. It is the lower parts of the wall (up to about 6 feet from the
ground) which have flaked, although on the higher parts of the wall, the
paint looks to be cracking and bubbling.

The mortar underneath is sound - that has not started to crack off the
bricks.

What is the best way to repaint it? Is it just a case of using a wire
brush to get off any loose paint,

Seems unlikely to be viable, why wouldn’t
the paint that hasn’t flaked flake off later ?

and then painting with Sandtex or some other outside emulsion paint? Or do
I need to first paint the mortar with some sort of primer and then paint
that with the white paint?