How to remove marks on walls left by Cabots Deck Clean?

[tarynM]

Help please!! We used the Cabot’s deck clean as our kwila deck needs restraining and it has left white marks on our external house walls. How do I remove this without damaging the black paint?

[MitchellMc]

Welcome to the Bunnings Workshop community @tarynM. It's terrific to have you join us, and many thanks for your question about repairing paintwork.

Unfortunately, you'll probably need to re-paint the area, as the strong chemicals in the deck cleaner have discoloured the coating. You could try scrubbing the area with a sponge and some warm, soapy water, but I wouldn't have thought the stain could be washed away as it's more-so damage to the actual paintwork.

Do you know the name of the paint colour, or do you have some spare?

Please let me know if you have any questions.

Mitchell
 

[tarynM]

I was really hoping it had just left a film and would be able to be cleaned off? 

repainting my entire house seems like a last resort option as it’s on multiple walls.

any other suggestions?

[MitchellMc]

The product is oxalic acid, @tarynM, which likely compromised the paint. If you match the colour, you could re-paint the affected areas instead of the whole house.

The product is fairly aggressive and designed to strip oils and stains from your deck. Unfortunately, the preparation instructions of protecting paintwork with plastic sheets and rinsing off immediately and thoroughly if contact occurs are there, as the damage caused is irreparable.

Mitchell