02/06/2026
This old downpipe had a few people guessing, but the rust gave it away straight away — cast iron.
Before doing any work on old gutters and downpipes, make sure you know exactly what you’re dealing with. Some older properties can have lead or asbestos cement rainwater goods, and you don’t want to be creating dust from either of those. We’ve put together a simple identification guide at the end of the reel to help.
Once we confirmed it was cast iron, all the loose rust was scraped and sanded back.
Our system on the metal section was:
✔ Owatrol Oil directly onto the rusted areas.
✔ Fleetwood Bloxx-It Black mixed with Owatrol Oil as the undercoat.
✔ Tikkurila Miranol High Gloss mixed with Owatrol Oil for the finish coat.
applied with 10mm microfibre roller and Aqua Glider Brush
The bottom section is being painted the same colour as the masonry, so we treated that area slightly differently.
We still applied Owatrol Oil to stabilise and protect the metal, but we didn’t add Owatrol into the Bloxx-It White. We’ve found that when a water-based masonry paint is going over it, adding oil into the primer can sometimes cause issues with the water-based system.
So for the lower section it was:
✔ Owatrol Oil.
✔ Bloxx-It White.
✔ Two coats of masonry paint.
A lot of people automatically paint downpipes black, but on a standard pipe like this we prefer to lose it into the wall colour. It looks cleaner, less fussy and draws your eye to the house rather than the pipework.
The important part is the preparation. Get that right and this shouldn’t need attention again for many years.
Check out the guide at the end of the reel and see if you can identify what’s on your own house.