Why is my plaster repair peeling?

[Garfield28]

Hi all, just wondering if anyone out there can tell me why my plaster repair I did about 8 months ago is peeling/flaking off please, would it be because of the moisture as it is in the bathroom? It mainly seems to be the feathered out thin edges that are the problem, I did have the same issue in my ensuite to a repair I also made there when fitting a new IXL heater/exhaust fan. 

If so would really appreciate and tips on how I can fix it, I didn't use any sort of primer underneath before plastering I don't know if there is such a thing or if it's required but would appreciate any tips to sort it and redo it. 

Thanks 

Geoff 

 

 

[EricL]

Hello @Garfield28 

Thanks for sharing your question about your plaster repair. Just to be clear regarding what I'm seeing on your photo, this is the painted ceiling where you've made some plaster repairs? You then painted over the repair without using a primer on top? 

It's possible that the paint did not get a good anchor on the surface of the plaster causing it to peel away. I suggest sanding the entire area that does not have primer on it and remove as much of the damaged paint as possible. 

I propose using the Crommelin 1L Flat Aquablock Waterproof Primer Undercoat - 1L. It's designed for high moisture areas and is perfect for your bathroom. You can then use your choice of acrylic topcoats tinted to your preferred colour.

Here is a handy step-by-step guide: How to paint like a professional.

If you have any other questions we can help with, please let us know.

Eric

[Garfield28]

Hi Eric,

Thanks for the reply and advice. 

I believe its mainly the actual plaster repair underneath that is peeling on the edges that were feathered out though. Should I perhaps scrape the repair off and redo but add a primer under the plaster repair you think? I think I read somewhere that PVA glue is also used as a primer for plaster in wet areas, do you know if this is correct? 

Thank you 

[MitchellMc]

On those feathered edges, @Garfield28, was the filler applied over the paint? That could be the issue. I'd suggest sanding the areas back until you reach the plaster sheet or at least the paper of it and giving it another go. The plaster might not have adhered to the painted surface as well as it did to the plaster sheet. Once you've sanded the area back, you can re-apply a topcoat of filler and then, when dry and sanded, undercoat with the product @EricL mentioned above.

PVA glue is not designed as an undercoat. It could work, but it's not something I've seen recommended by any manufacturer.

Please let me know if you have any questions.

Mitchell