How Should I Fill Holes In A Plaster Wall That Have Broken Into The Cavity?

[Rodge2]

The holes are 1cm diameter, some are a bit less. Polyfilla would drop down into the cavity I think. Would that expanding foam be an option? and then Polyfilla on top? Or is there anything I could use that provides more strength? They are quite deep, maybe 2 inches. Looking for advice on the net has just turned up info on plasterboard walls. Thanks.

[Khandro]

Cut a piece of card slightly larger than the hole, in the centre make a hole through which thread a piece of string and tie a knot on one end, flex it and push through the hole in the plasterboard and using the string in tension pull it so that it is against the back of the hole, you can keep it in place by taping the string to the wall.
Gently add some polyfilla to a few spots around the edge and let it harden, the you can nip off the string and fill the rest of the hole with filler.

[murraymints]

have done that Khandro !

[Old_Geezer]

Sounds, from the description of a cavity, like you have one if those plasterboard walls. As it is only a 1cm diameter hole then I think best just bung enough filler in to fill it regardless of how much drops inside, and sand flat when dried.

Were it larger then the way I'd tackle it, and I may be approaching it all wrong, would be to stick some plasterboard on the inside, let it set, then filler, or a further piece of plasterboard, has something to stick to.

[theshedman]

The way Khandro says is a good idea or you could use a small piece of plasterboard instead of the card. A good idea is to put some quick drying glue onto the piece you put in the hole and let it set before using polyfiller.

[Rodge2]

The wall isn't plasterboard, it is traditional plaster, about 2 inches thick, so I can't get anything to the back of it.

[HansUrbancka]

Your initial question indicates that the holes have broken into the cavity. However your posting at 8.19 says otherwise. Consequently if the holes Do Not go through into any cavity and are only about 1cm dia., then straight forward Polyfilling is all that is necessary. Push the Polyfiller into the holes with in with the top of a pencil or something similar and smooth off with a Palette Knife.

Cheers... Hans.

[Rodge2]

Sorry I don't know much about this and am having difficulty identifying what I'm dealing with. I have had another look at it, and I can see what you all mean, it must be plasterboard to have the cavity present. I will have a go at some of your suggestions this afternoon, and let you know how I get on. Thanks for all the advice, really appreciated :)

[Hopkirk]

I would slowly close the hole with small wipes of polyfilla left to dry for a while.

[malagabob]

Khandros sugestion is the way I’d go about it or similar. Or using poly filler or some other filling medium. Just get or mix up enough, and over a few days keep adding small amounts to the circumference of the hole, building up on previous applications till the sides meet. Then allowing to dry, finish off.

[bhg481]

If the holes are as small as 1cm then Hopkirk's method will be fine. Mix the Polyfilla fairly thick or use pre-mixed from a tube. You'll never get a card behind 1cm holes.

[melv16]

Baco foil scrunched up into the hole works well.