How to fix this hole

[Monket]

Grateful for any advice on fixing this hole in my ceiling! It’s a sloping ceiling, in case that makes any difference, and the hole is about 10cm diameter.

Put some poly filler in it

Polyfilla, using a flat plaster blade let it harden. Sand it smooth in a gentle circle pattern using 180 grit sanding paper.

It's small put some ready mix plaster and fill and flatten off like if you were smooth icing on a cake. Slightly over fill it. Once it's been dry for about a week lightly sand over with fine sand paper.

Filler but do a few layers keep adding small amounts let it dry then add more if you do it in one go it sags

If you use a broad metal filling knife you can press it very flat, with the knife bridging over the hole and levelled on the plaster on each side.

When it is cheesy hard, but not dry, use the knife like a razor to shave off any filler above the surrounding surface. There's no benefit in putting on more than you need so that you have to grind it off later, which is extra time, effort and makes dust.

I find Joint Cement, which is a sort of plaster, better and easier to use than filler. It sets quickly and does not sag.

When you paint it, apply two mist coats of thinned emulsion to prime the bare surface first. Polyfilla will go soggy when wetted.

OOI, what made the hole?

Thank you so much for all the replies! I don’t know what made the hole, it just cracked in that area and then gradually worsened and eventually a chunk fell down…

I suspect the plaster popped off because that plasterboard nail isn't fixed in properly and the board has moved a bit. I would get a nail, put it so one end is in the middle of the nail in the plasterboard and hit it a couple of times so it is fixed in a bit better. Careful not to put the nail all the way through the board, then filler it as above.

Our house was COVERED in these holes, dozens of them - all internal plasterboard walls (bungalow) They happen when there is some movement in the plasterboard and it pops off over the head of the pin.

As long as the actual pin head is below the surface then filler, as above, is the way to go, but in addition we were advised to coat the hole with dilute PVA glue before filling. Seems to have worked fine, lovely smooth walls now.

"the hole is about 10cm diameter."

That's four inches.

If it is a popped nail (seems likely) it is considerably smaller.

BTW, rather than hammer a nail in ( may cause more cracks) you could drive in a screw. Plasterboard workers favour black bugle-headed screws, I don't know why. A galvanised one will resist rust (plaster and filler contain water) which may stain.