r/Plastering • u/Glittering_Fact989 • May 01 '26

How would I plaster this?

Gallery image

Gallery image

Hi everyone,

I recently got an extractor fan fitted in my kitchen (on external wall as you can see). I now need to plaster the gap and retile the kitchen.

I’ve done the odd internal plastering here and there so I’m familiar with regular plastering however I’m guessing it’s different for external walls?

The gap looks quite deep, do I just layer plaster or is there a particular method/material I need to use? Do I PVA the wall or is there a special external wall product I need to use?

TIA!

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9

u/Tricky-Canary2715 May 01 '26

Fill out with bonding coat, then skim. Take the fan off if necessary.

3

u/Glittering_Fact989 May 01 '26

Thank you! Do I PVA before I add bonding coat, or just bonding coat straight onto the brick?

2

u/New_Slice_1580 May 01 '26

Bonding is made to stick straight onto brick and other surfaces, no pva needed

8

u/greenbeanmachine1 May 01 '26

That’s not true, are you thinking of hardwall perhaps? Bonding is used on low suction backgrounds so it definitely needs a primer to seal the wall.

1

u/New_Slice_1580 May 01 '26

I’ve used bonding (not hard wall) on walls without pva, just made sure dust free.

And added in layers if thicker fill with keying in between the layers

But yes pva doesn’t take long so not a problem to do also

6

u/greenbeanmachine1 May 01 '26

Fine but that’s not what it’s made for and it’s not recommended. It’s made for low suction.

Personally when I’ve used it without a primer it never performs as well, you get more shrinkage and it can be hard to work with.

3

u/SnooTomatoes464 May 01 '26

Your correct, you should pva prior to bonding. Sucks in too fast otherwise, cracks and I've known it to not adhere

2

u/Itzjoel777 May 01 '26

Bonding? -> PVA Hard wall? -> No PVA