I have quite a few cast iron hoppers and downpipes that are showing rust. I don't want to replace them with plastic - there are too many and some of the hoppers are embedded in the roughcast render - so what's the best way to tackle them. Fully stripping the existing paint isn't really an option ... so what do I do?
Painting cast iron downpipes
Apr 29, 2026
Last reply: 2 months ago
2 Replies
Hammerite Direct-to-Rust, despite the name it does need loose rust/paint removing but not all the way to bare metal ...
Wire brush off the loose rust and paint[1], then use a direct to metal hammered or smooth finish paint.
[1] by hand, or wire cup brush / poly paint removal disc on an angle grinder if there is a large amount to do.Join the Discussion
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