Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit

Radiator Painting

I think the old school rustolum red primer is still the oil based stuff that works. It's the new "industrial" You know, "made it better stuff" that peal and stinks.


  • Scott Kuchta
    Scott Kuchta Member Posts: 9
    Radiator Painting

    I read Dan's book, "We Got Steam Heat!". A great book, I've learned a lot but I have a few questions. Dan mentions how painting steam radiators with metallic paint reduces their radiant capacity. He also says it's the last layer that affects the radiation. Does this mean I can simply wire brush the flaking metallic paint on my radiators and paint them with non-metallic paint to restore their radition potential or does ALL of the metallic paint need to be striped or sandblasted off first?
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928

    The final coat is what affects emissivity (radiation). Doesn't matter what's underneath.
  • Phil_8
    Phil_8 Member Posts: 39
    clear coated CI rads

    What happens if the final coat is a "clear coat". A local shop removes all of the paint, wire brushes the rads and then applies a high temp. clear coat. The rads come out looking good (a chestnut brown/grey). Just wondering how the clear coat affects the radiation.
  • Dirk Wright
    Dirk Wright Member Posts: 142

    You'd have to look up the emissivity for any particular final coating, but there is another issue which is the thermal conductivity of any layers of paint between the cast iron and the final coat. The heat has to conduct through there before it is emitted off the outside.

    My gut impression is that, if I had these things, I would want to blast them and get them metal plated, like a nice black nickel or something with a high emissivity.
  • JB_8
    JB_8 Member Posts: 85
    clear coat

    Don't know about clear coat,but sandblasting and powdercoating is about $100 per radiator & looks nice.Get any color you want but remember the shut off valve that is not sent out. Now is not the time of the year to do it because you will not have radiators for about a week.
  • thfurnitureguy_4
    thfurnitureguy_4 Member Posts: 398

    Clear coat is not the answer. It will not handle the heat your options with clear are lacquers, they will craze and flake very quickly and polyurithane, plastic will smoke and melt off You could use the vehicle from oil paint (deep base for oil paint)but it is not real clear. Flat oil base house paint or latex works fine. NOT rustolum industrial it is a urithane. Check if there are any clears in powdercote. Powder is cured at 400F + -
  • D107
    D107 Member Posts: 1,726
    oil base, latex finish

    just removed all the old wooden radiator covers (hot water system), wire-brushed the 1920s large tube US radiators and primed with rustoleum (non-metallic) white oil-based 'clean metal primer' then topcoated with white latex. They're putting out so much they overshoot the thermostat after the boiler shuts off. hope the rustoleum wasn't a bad move.

This discussion has been closed.


It looks like you're new here. If you want to get involved, click one of these buttons!