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

Why are radiators painted silver?

HeatingHelp Posts: 465
edited August 2016 in THE MAIN WALL
Why are radiators painted silver?

Ever wonder why so many of the old radiators you see are painted silver? Paint that contained flakes of metal (aluminum or bronze) had a way of cutting a radiator’s output by 20 percent so they started painting radiators that distinctive silver color.

Read the full story here


  • kkrrjr
    kkrrjr Member Posts: 12
    Damn, and when some oldtimer said the paint made the rads better, I believed him. The catalogs said you had to use thier special paint and I believed that. What a gulable kid I was way back then. Thanks for straightening me out.
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 15,429
    I guess if they were oversized it did make them better. Thanks for reading me!
    Retired and loving it.
  • Henry
    Henry Member Posts: 988
    My father always had a can or bronze or aluminium paint in his truck.
  • TMcGroy
    TMcGroy Member Posts: 15
    Thanks for providing a concise answer. Since buying a house with radiators painted silver, white & pink 23 years ago, I've been trying to find out what one color I should paint them to achieve the most efficicency.

    Now, can someone tell me how to remove the chipped & worn (presumably latex) paint with rusting metal underneath in the bathroom? Then, what should I seal it with to maximize efficiency & prevent more rust?

  • Erin Holohan Haskell
    Erin Holohan Haskell Member, Moderator, Administrator Posts: 1,697
    @TMcGroy - A lot of pros recommend sandblasting it or having it taken somewhere to be sandblasted and powder coated. Here's more info:
  • Nimrod66
    Nimrod66 Member Posts: 13
    I've been hashing this subject over with some friends who are engineers. They contend that radiation is such a small component of the output from a cast iron radiator compared to convection that paint color would have a negligible impact on radiator output. Radiators may have been painted silver because a lot of folks believed in a heat retention theory, but it is likely not true, based on what my engineering buddies say, that reflective paint reduced heat output noticeably (or that another paint color then increased radiation noticeably).
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 15,429
    From an old radiator, radiator was 40% and convection was 60%. I've read that in every old book I own.
    Retired and loving it.