grit

So I’m reskimming this wall, I rolled yellow grit on it first and then levelled it up with some bonding (wall was curved) . Before I skim with multifinish tomorrow, should I PVA the bonding or shall I roll some more yellow grit on it?

Any of you plumbers got any thoughts on this please. Brother in law has Worchester heat only boiler, linked to an unvented cylinder. (Centerstore)... was all new in 2013. He was saying the pressure wasn't very good on his taps... it was the cold feed, which I thought doesn't go through the...