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Ventilation Openings Under Radiators

alw19 Member Posts: 3
I'm working on a building with a two-pipe steam system. Underneath each radiator in the building is an opening directly to the exterior. I've attached an file showing two images - the left image is an infrared shot of a radiator from the interior, showing heat loss through the opening; the right image is a photo of the ventilation openings from the building exterior.

The building is in a cold climate, so these uncontrolled openings seem like a source of heat loss and a waste of energy. A few questions:

1. Is there any reason NOT to seal these up? I've been assuming that, historically, these openings are just to help bring in fresh air in the winter, but is there some other purpose for these that I'm not aware of?

2. Any suggestions on how to seal these up? They could brick them up from the exterior, but the brick would have a different color. And they're hard to access from the interior with the radiator in place. Batt insulation? Spray foam? Any thoughts? I'm also wondering if these openings have dampers in them; if they do I couldn't find them.

Has anyone come across this before or have any suggestions?


  • Steamhead
    Steamhead Member Posts: 16,842
    That building

    was probably built as a school. The fresh air openings were a Code requirement for schools then, and most areas still require a fresh air source today.

    What is it used for now?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    closing openings

    can you find some sort of decorative medallions, perhaps made of molded concrete to cover the openings? maybe there are some which could provide a visual theme for the building.--nbc
  • alw19
    alw19 Member Posts: 3
    Building Use

    Yep, Steamhead, it was built as a school. 1915 original construction date. But it closed as a school more than a decade ago. It's been very intermittently used since then, but the client is repurposing it as a community center. Even with it's new use, the building won't be as densely occupied as it once was as a school.

    No mechanical ventilation has been added, and there are no plans to add any. All of the windows are operable, so I don't see the added ventilation benefit of having these facade openings.

    Am I missing something?
  • alw19
    alw19 Member Posts: 3
    great idea!

    that's a great idea, nbc - very creative. i'll definitely float that to the client as a possible solution. thanks for the input!
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