rendering, onto painted surface

[chelseakeith]

Hi Guys
i am going to render a new extention but will need to render onto excisting build. this has been painted. will it be ok to render on top of the paint or will it need to be removed? the paint is not flaking and is in a good state. if ok to render do i pva for a key?

 

[beddy]

never use pva for a key externally. sbr cement slurry instead

 

[Pug]

or rendaid

 

[Render Systems]

I would rough the surface first with angle grinder to get a key

 

[lucius]

NEEDLE GUN

 

[S a plastering]

or rendaid

shouldnt use rendaid over paint ask weber the paint should be off really first

 

[dav]

Same as Render Systems mate,whenever we are going over painted brickwork we score the surface with an angle grinder to provide a key!