Thinking of buying a newish house and noticed on the viewing that the plaster tape used in the corners was starting to crack and lift.

What’s the best way to correct this?

Also interested in an answer to this.

NHBC warranty ? Get redone before decoration, otherwise scrim and re skim

An easy fix assuming its not too bad is to use a primer sealer to stick it back down with. My weapon of choice is Zinnser Gardz, make sure you poke the brush under the offending tape as well as painting over it. You might have to push it down several times until it stays ( when the sealer reaches its tacky point) but it does seem to hold well. A cheaper alternative would be pva.
You will of course need to touch up with paint after its dry.

Out of warranty and only a few patches. I’ve used no more nails to glue the odd patch. Pretty much grabs it instantly. Just wondered if there was a better idea.

Think the ultimate fix must be to replaster but that’d be a pricey solution.

Assuming modern plaster board. Construction and your redecorating anyway

Best /most time comsuming and messy would be to pull it down and redo it – with metal corner paper tape.

Scrim is for butt joints not corners it will crack again using scrim.