Our open porch is painted with emulsion (unsure whether it is exterior grade) which has a 'silk' look to it. It's now filthy so I want to repaint the walls. Do I need to sand off the sheen prior to painting (with Dulux Weathershield Matt Emulsion), in the same manner that internal silk emulsion needs to be prepared?
Or would the roughness of the render mean that the new emulsion has something to bond into?
Or would the roughness of the render mean that the new emulsion has something to bond into?