On 09/10/2020 22:31, JohnP wrote:
Many years ago we painter the coving in our lounge a dark green (Farrow &
Ball).
SWMBO now wants it a light beige.

Any tips for blocking out the green before the beige. Is just a few coats
of white emulsion the only way?


It took years to realise the mistake ? :-)

Try stain-block paint.