render paint flaking off

[divingmoose]

Hi,
The rear of our house was rendered and painted about 2yrs ago before we bought it. I have noticed that in a couple of spots the paint has flaked off and the render underneath has gone really sandy to the touch, you can rub it and the render rubs away. Its only in a couple of spots and i think its were two wall mounted plant pots were located and the water used to run down the wall when watered.
Is there any product i can put on this part that is effected before the render is painted again.
Thanks Lee

 

[misterhelpful]

Providing the render is not blown (hollow sounding) or cracked, you should be able to get away with using a stabilising solution or diluted exterior PVA to seal the surface before re- painting.

Scrape away any flaking paint and brush off the surface dust before applying either.

My only concern is, that as you said the surface is sandy and can be easily rubbed away, the original render mix was too weak. If this is the case then the problem will spread in time, but if it seems limited to an area that was often wet, hopefully not.