Originally Posted by Scout 30
I think I would try just cleaning
with TSP & top coating a small area to see how it does.
Problem is that a lack of adhesion can take a long time to become apparent.
Top coat on my deck
had grit added. Job was done by a previous owner and now that it's starting to flake off I can see that not only did he not prepare the substrate - he painted over mildew, dirt, everything.
Some places the paint's firmly attached, other places it just peels off.
OP's paint surface needs abrading. Sanding
will work but will remove grit.
wire brush used by hand will "work around" the grit, so will Scotchbrite.
Could be years later that today's shortcuts kick you up the arse