Just wondering if anyone can give advice on how to clean, repaint and seal a reconstitued limestone wall?
Welcome to the Bunnings Workshop community. It's wonderful to have you join us, and thank you for sharing your question about your limestone wall.
Just to be clear about the current condition of your limestone wall is it currently painted with ordinary paint? Has it been sealed before with another product and the surface is now degrading? Would it be possible for you to post a photo of your wall? This will allow our members to assess its condition. We can then make recommendations on how to clean and seal the limestone.
If you need a hand posting the photos, please let me know.
Sorry for the late reply, I work away and just returned home.
Photos have been uploaded.
Thanks for posting those photos of your limestone wall. It looks like the limestone wall has been previously painted. I suggest using 30 Seconds 5L Outdoor Cleaner Concentrate in combination with Oates Long Handle Deck Scrub Brush to remove the moss and mould buildup. Please make sure to give the 30 Seconds enough time to activate before you start scrubbing.
Make sure to wash the wall clean and then follow it up with another wash, but this time use water and detergent in a bucket. The purpose of the soap wash is to remove any oil or grease build-up on the wall. Please rinse the wall thoroughly so that all the soap residue is removed. I suggest using Dulux Weathersheild to repaint your limestone wall. This would also be a good time to make repairs and fill in any gaps in the wall.
Sealing the limestone is only ideal if the limestone was not previously painted. When paint is applied to limestone it travels down into its pores and embeds itself. Removing it is next to impossible and your only option is to paint over it.
If you need further assistance, please let us know.
Thanks Eric, your advice is greatly appreciated and will be heeded.