How To Refinish Reclaimed Cast Iron Radiators

Cast iron radiators have a distinctive appearance and look great in older or more traditional style buildings, but when buying a reclaimed antique radiator, there is often some restoration work that needs to be done.

A note before we begin - you will likely need to do a lot of this outside, so even though it might seem obvious, be careful when moving a cast iron radiator - it’s not uncommon for them to weigh upwards of 130 kg.

• Remove the existing paint. Layers of old paint looks unattractive, can stop your radiator from working effectively and, depending on how old it is, the paint could even include lead. You may need to have the radiator sandblasted if you really want to remove all of the paint. But if you’re less concerned with getting all the way down to the metal and are more focused on just getting rid of the paint that is flaking off, you can use a wire or other hard bristled brush to remove any large flakes and then give it a light sanding manually.
  
  
• Clean the radiator. Dryer vent brushes are great for getting in between the fins and clearing dust and dirt out of the inside of a cast iron radiator. Clear away any pieces of paint and then thoroughly clean the radiator with a TSP substitute. This removes any additional dirt or grease and deglosses the surface to prepare it for painting. Rinse off the cleaner with a power washer or hose with a jet setting and then leave to dry overnight.
  
  
• Use a paint primer. Before you paint your radiator, prime it. If there’s some rust on the surface, you might want to consider using a primer specifically for rusty metal. Otherwise, there are a number of different oil-based primers you can use - be sure not to use a latex or water-based product on cast iron or it could rust! If you’re not sure which paint primer to use, check the instructions on your paint - they might recommend a certain type of primer, or they might even say not to use one at all.
  
  
• Paint the radiator. Once you’ve primed your radiator, it’s time to paint. Look for a paint that is designed for use on radiators or high heat and opt for a spray paint over a brush to make sure you can get in between the fins. Glossy finishes are easier to clean, but can accentuate flaws, so if the surface of your radiator isn’t perfectly smooth, you might want to consider a matte paint. Some radiator restoration specialists offer powder coating, however, cast iron isn’t designed to go through the baking process of powder coating so there is a real risk of it damaging the seals between sections, resulting in leaks. 

When you’re done, you should be left with a radiator that looks as good as new! Hire a plumber to connect it to your central heating system and you’ll have your own beautiful antique radiator.

If you’re looking for a cast iron radiator for your property, see our current stock of radiators.