How to repaint peeling weatherboards?

[Daz591]

Hello. I am preparing my external weatherboard for painting. The old paint is quite flaky. I have sanded a section of it multiple times with 80 grit sandpaper to start. It appears smooth, however after about 24 hours later the smoothed area seems to be flaky again. (Before I get to prime and undercoat it). See the photos.  Should I be sanding it back to the bare boards, or use a product like "Peel stop" by Zinzer? or another similar product? If I use a prime undercoat on the surface with slight peeling, will this continue peeling? Any suggestions are welcome.  Cheers...Darryl

 

[EricL]

Hello @Daz591 

Yes, you can use the Zinsser Peel Stop Binding Primer Clear 1L on the sanded weatherboards. However, I also suggest using a more aggressive sander such as a Ryobi 800W 76mm Belt Sander especially if you feel that your current sander is not sanding the surface enough. It would be better in the long run to remove all of the old paint on the surface and start fresh, as there is always the possibility of the old paint peeling off the surface.

Please remember to wear personal protection such as gloves, goggles and a mask when sanding the surface. 

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

Eric

[Daz591]

Thanks Eric.

If I manage to remove all of the old paint by sanding, I will then use a primer, sealer, undercoat before the topcoat?

Darryl

[EricL]

Hello @Daz591 

Yes, using a primer, sealer, undercoat is a good way to prepare the surface of the weatherboard for the top coat. 

Eric

[Daz591]

Thanks Eric. 

I better get started I guess.

Cheers

Darryl