Cornice adhesion to gloss painted surface/wallpaper adhesive

[bh619]

Any recommendations for preparing a gloss painted walls and wallpaper adhesive surface for cornice adhesion?

I have most of a bag of CSR cornice cement and was planning on using this. But, the walls are either old gloss painted or have wallpaper adhesive/primer (wallpaper is removed and the house is from the 60’s), so I am thinking I will need some sort of primer to get better adhesion of the cornice cement to the wall - particularly as I have plastercast cornice 145x115mm. I have done a quick sand at 60grit but most of it still feels pretty smooth.

I saw a video of someone using spray adhesive Trim-Tex along the section that the cornice bead will be, to make it a rough surface once dry. Are there any other options? (I can’t find a local store that stocks trim-Tex in Perth)

[EricL]

Hello @bh619 

I propose breaking the surface cover with Zinsser PaperTiger Wallpaper Removal Scoring Tool in combination with Zinsser 650ml DIF Liquid Concentrate Wallpaper Stripper along with a very sharp paint scrapper. I understand the wallpaper has been removed, but this is to break up the petrified wallpaper adhesive. However, before you begin, in the interest of health and safety, I suggest having your wall tested for asbestos first. If the test is positive, you'll need the services of an asbestos removal specialist. If the test is negative, you can proceed with your project. 

On the condition that there is no asbestos on the wall, I suggest using an Ozito 800W Belt Sander BSR-7000 to totally strip the wall of paint and wallpaper adhesive. Please remember to wear personal protection such as gloves, goggles and face mask. I recommend starting with a low grit, either 60 or 80 to strip the hard surface paint. Please note that if the sandpaper is too rough it will eat into the material of the wall as well.

I propose looking at using BondCrete to prime the surface before you use the cornice cement. Make sure to follow the application instructions on the container. My best advice is to remove all the sanding dust and making sure that the surface is clean and free of debris.

If you need further assistance, please let us know.

Eric

[bh619]

Thanks Eric,

The walls look to be hardwall plaster over cement render on a brick wall - did these often contain asbestos?

Cheers

Ben