Hello,
I’m planning to build MDF or plywood covers for old cast iron steam radiators. All of the ones I’ve seen have one inconvenient feature in common, which is that the top surface gets hot—not dangerously so, but enough that you have to be careful what you put on it (e.g. no wax candles…).
I’m wondering if it would help to put some rigid insulation underneath the top section. Anyone have experience doing this (or any other method)?
Thanks!
Replies
Study up here
https://www.finehomebuilding.com/?s=Radiator%20cover
and google could be your friend.
Remembering of course that they are supposed to be decorative and disburse heat. When not using metal, plan on directing the heat out rather than radiate. Good entry venting at the bottom and a sweeping larger opening at the front and up top (here a curve or angled panel to direct it to the front exit”.
There’s probably some sort of magic ratio of bottom to top vent “area” to create a chimney effect.
I’d be hesitant with foam.
I grew up with steam radiators, no covers but we did have aluminum skinned ridge foam behind them with the idea of pushing the heat out rather than into the horsehair plaster and lath walls, not sure if it actually helped.
foam seemed to survive well
great article in the link
good luck
Thanks to all for your responses. I hadn’t thought about the fact that insulation on the top would prevent or limit heat from radiating upward (although it would be unrestricted to the sides and front). I think the occupant could be the judge from a performance perspective, though.
The larger concern is safety. It appears that EPS foam can safely function up to 167 degrees Fahrenheit. Here’s a nice source for data on EPS: https://omnexus.specialchem.com/selection-guide/expanded-polystyrene-eps-foam-insulation Google says cast iron radiators can easily exceed 200 degrees Fahrenheit on the surface. I don’t know how fast that temp falls off in the air around it, but nevertheless those specs don’t seem compatible.
So it sounds like there are good reasons why nobody does this. :)
Thanks again.