How to fix poorly adhered paint on plasterboard?

[tarragindi_haus]

 

Hi

I have an older house where the paint in one of the rooms has really poor adhesion. I suspect that this is because the room used to have wallpaper and perhaps the wall wasn’t properly prepared before being painted.

I would prefer not to reline the wall with new plasterboard as it’s a pretty expensive exercise.

Is it possible to repair this by:

- sand the paint back to bare plasterboard using a plasterboard sander

- skim coat the walls using gyprock multipurpose joint compound

- sand to smooth out the finish

- repaint, starting with a decent primer 

would this approach work? Is there a better way?

[JacobZ · Accepted solution]

Hi @tarragindi_haus,

Thank you for your question about fixing poorly adhered paint.

The steps you've advised are exactly what is needed, but it is unlikely you'd need to skim-coat the entire wall.

I'm fairly confident that the problem is because the wall wasn't adequately primed before the paint was applied. If it was primed correctly, you would see another layer under the paint. Where the paint has peeled back, you can see bare plaster, and no second layer below the paint, which indicates there is no primer.

My suggestion is to scrape back the poorly adhered paint using a paint scraper. As there doesn't appear to be any primer, this will likely be quite easy.

Once the paint has been removed, you can assess the state of the wall before proceeding. I doubt you would need to skim-coat the entire wall, but if there are some areas that are a bit average, I would suggest using a topping compound such as this Gyprock CSR 2.25kg Less Mess Topping Compound. Topping compounds are lighter and easier to sand, so you will be able to get a smoother finish using this.

Give any imperfections a sand with a sanding sponge to make them nice and smooth. If there is a lot of sanding required, you can use a plaster sander. 

Once prepared, use a water-based primer such as Dulux 1Step Prep Primer, Sealer & Undercoat followed by a water-based paint such as Dulux Wash&Wear Interior Paint. 

Check out How To Paint A Room for some guidance on the painting process.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob

[tarragindi_haus]

Thanks heaps for your help Jacob

In terms of the paint scraper, would one like the below be suitable?

https://www.bunnings.com.au/uni-pro-100mm-heavy-duty-wall-stripper_p0149280?store=8087&gclsrc=aw.ds&...

[EricL]

Hello @tarragindi_haus 

The UNi-PRO 100mm Heavy Duty Wall Stripper will definitely work, I'm just worried that the tool may be too rough and damage the surface of the plasterboard. I suggest using something a little less aggressive such as the 100mm Sharp Edge Paint Scraper. It has the same width as the UNi-Pro stripper but is not as heavy and should allow you better control when scrapping the wall.  

If you need further assistance, please let us know.

Eric