I’m looking for a bit of advice. I have an external windowsill which needs to be repainted. It’s made of concrete, but has about 6 layers of paint on top, which is flaking off quite badly.
I have 2 issues. Firstly, the window itself is uPVC. It has been sealed on the outside but the sealant has been against the top layer of the sill paint. The paint is flaking off, and this is leaving a gap of a couple of mm between the sealant and the sill. Assuming I scrape all the paint off, this will make a gap the whole way along. Do I need to seal this in some way, and if so, how can I do that? Or would it be enough to just shove some paint into the gap and let that seal it?
Secondly, do I need some kind of primer on the sill? I have masonry paint which was used for the other sills, so I’m using that for this one too. How do I get the surface of the sill ready for painting? A lot of the paint is peeling off right back to the raw sill, so I plan to scrape it all back to even it out.
Thanks for any advice!