Preparing an outside wall for painting

Hi The current paint on our boundary wall is peeling off and today I want to start preparing it for unibonding and painting - any suggestion please.
Thank you

The only way I know is elbow grease with a paint scraper and a good brushing down. That's how a painter did one for me lately on an outside wall 15ft x 10ft tall. Powerwashing maybe but there may still be flaking when it dries out.

Bee

Depends on how big the wall is. We had a painter do all the walls on our community and it started peeling and flaking because no preparation was done. I used an electric sander for most of it plus the aforementioned scraper.

Painted it with a paint recommended by the Cadena 88 DIY by Consum and, touch wood, no peeling in the last 6 months or so.
That was just a white painted wall, though, and the same technique with the balustrades is working well.

Yes I forgot he used the sandpaper where he thought necessary.

Bee

Hi thanks - we are starting with the road side wall 40sq.m, today we have brushed and scraped the wall, then power washed, a lot of flaking has come off - going to sand it soon, then unibond before painting tomorrow.
I have to pop to garage and see what paint we purchased which was recommended by the shop.

willemite wrote:Hi thanks - we are starting with the road side wall 40sq.m, today we have brushed and scraped the wall, then power washed, a lot of flaking has come off - going to sand it soon, then unibond before painting tomorrow.
I have to pop to garage and see what paint we purchased which was recommended by the shop.

Why would you unibond the wall before painting it? The masonry paint needs to grip and sink into the render. If you unibond the wall, it wont grip to it. It will just flake off again, in a year, or before.

Pressure washer to remove all loose flakes, and if my walls are anything to go by, there will be more loose than you think, so well worth while. Definitely no need for sanding, why would you, if you can’t remove it with a pressure washer I don’t see what sanding will do. I then used a 50:50 water / bleach solution with a roller, all over the wall and plenty of it, to kill any mould that may or may not have been there. Don’t see the need for unibond, all that does is slow the absorption rate of the water in the paint. Instead, either use a watered down paint mix as your primer if u wish. I continued with the final layer of paint, it covered well, and three years later it is still good, no flaking and no sign of it coming off. So I’m pleased with the above procedure and how long it’s lasting. Hope this helps. Good luck with yours

daz wrote:Pressure washer to remove all loose flakes, and if my walls are anything to go by, there will be more loose than you think, so well worth while. Definitely no need for sanding, why would you, if you can’t remove it with a pressure washer I don’t see what sanding will do. I then used a 50:50 water / bleach solution with a roller, all over the wall and plenty of it, to kill any mould that may or may not have been there. Don’t see the need for unibond, all that does is slow the absorption rate of the water in the paint. Instead, either use a watered down paint mix as your primer if u wish. I continued with the final layer of paint, it covered well, and three years later it is still good, no flaking and no sign of it coming off. So I’m pleased with the above procedure and how long it’s lasting. Hope this helps. Good luck with yours

I do believe that using a power washer in the street is ilegal? Pete.

Remove loose paint, unions / pva and paint with gloss/satin gloss. Will clean easily and last many years

-BLUE- wrote:Remove loose paint, unions / pva and paint with gloss/satin gloss. Will clean easily and last many years

On render?