How to repair plasterboard in European laundry?

Question

Hi,

I have now pulled out the shelves and removed the existing doors and architraves from the cupboard that I am converting to a laundry.

After removing the door frame there are a couple of areas of plasterboard that need to be patched/repaired. I’ve watched so many repair videos that show different methods, I’m now not sure what method to use!

Photo 1: this joint was never taped as it was covered by the door frame. As the gap is approx 1cm in spots I’m wondering what the best method is to finish this.

Photo 2: the plasterboard edge has crumbled in spots and isn’t level with the interior plasterboard wall. I will be extending this out by about 12cm (probably by attaching a piece of timber) So I’m not sure whether to repair it first using an aluminium corner bead/trim, or just fill and patch as needed once the wood has been added.

Thanks

Tracy

MitchellMc · Answer

You'll find that many of the answers out there will work @Scootergirl. There's not necessarily just one way to do a job and, sometimes, not even one that would be the best way. Regarding the joints, the correct process is to tape and apply joint compound to them. This advice would come from the CSR Gyprock plasterboard installation guide. So, whether the joint is being tiled over or not, CSR advises taping joints. Also, our tiling adhesive companies advise that the joints need to be taped.

There is typically no need to prime new plasterboard if you are using something like

https://www.bunnings.com.au/dunlop-5-5kg-wall-tile-adhesive_p6829311

. However, any joints where topping compound has been used, or raw gypsum is exposed, need to be coated with

https://www.bunnings.com.au/dunlop-1l-primer-additive_p6829434

.

Mitchell

Scootergirl · Answer

Thanks for this Mitchell. I’ve worked out how to do the other repairs needed - I just wasn’t sure of the best approach for these 2 particular spots.

I will also be replacing the plasterboard around the laundry trough with water resistant plasterboard, and then tiling the splashback. I know I need to fasten this with extra screws to allow for the weight of the tiles - do i need to paper the joints? Some tutorials say that you do, but others say that you don’t!

And do I still prime the new plasterboard if it is being tiled?

It’s so tricky when there seem to be so many different answers out there!

MitchellMc · Answer

Hi @Scootergirl,

It really comes down to the level of finish you're aiming for.

If your plan is to paint the walls, I'd be looking beyond just repairing those areas. From your photos, there appear to be quite a few defects in the paper facing of the plasterboard. Normally, plasterboard has a smooth paper surface that seals the gypsum core, but it almost looks like the top paper layer has been peeled away in places, leaving a rough, fibrous surface. Even after filling and several coats of paint, that texture is likely to remain visible. Given the condition of the board, I'd be considering removing those sections and installing new plasterboard to achieve the best painted finish. Alternatively, you could topcoat it and sand the area smooth. This could be more work than simply replacing the plasterboard.

If, however, the area will be tiled, covered by cabinetry or concealed with timber, then the existing plasterboard should be perfectly adequate. In that case, you can simply tape the joint in Photo 1 with paper or fibre tape before applying joint compound to bridge the gap.

For the corner in Photo 2, an external corner bead is only really necessary if the corner will remain exposed. If it will be hidden behind your timber extension or cabinetry, I'd simply fill and patch the damaged areas as required once the timber has been installed.

Please let me know if you have any questions.

Mitchell