reflective backing

Ted_4

Here's a flir image one of our auditors took recently of a brick house that had not had any weatherization treatments. The radiators stand right out - and this was on a relatively warm day. I'll post some pictures later if we get the job, and install radiator reflectors.

Eileen Olive

Reflective Backing @ Radiators

What is the best reflective backing to put between my radiators and the outside wall? I have seen rolls of what seems like bubble wrap with reflective coatings on both sides at Lowes and Home Depot. Are these any good, or is there a better option?

Eileen Olive

Not worth the effort?

Should I take this to mean it's not worth putting reflective material behind a radiator that sits against an outside wall?

mark ransley

I use foam board with dual foil face, Polyisocyanurate is R 7.2" and about 15$ for a 4x8 at HD. You must completly seal the board edges to wall with a big big bead of caulk, and screw in or it will be the coldest wall and will condense behind the board and mold. I dont know why this isnt discussed more. Outside wall radiators must loose everyone alot of money heating the outside. 2" would be better and then you paint it. It has foil so it reflects Radiant into the home

Eileen Olive

Interesting

I cannot help but wonder why that would happen behind the refelective board?? And caulking it to the wall stops this effect?

steve_201

Cool wall

The reflective surface and insulating foam combine to keep the heat away from the wall. The result can be a very cold wall upon which which any moisture in the air will condense. By caulking around the foam you keep moisture laden air away from the cold surface.

Eileen Olive

Is it worth the trouble?

Is it worth putting a reflector behind stand-up radiators? I mean, is the energy or heat actually reflected back into the room?

David Nadle

mounting

I made a set of reflective panels by laminating metallized mylar to some eucaboard cut to size. I just set them in place or held them in place with one screw. Becuase there is room for air to move behind the board I don't think caulk and such is necessary. I seriously doubt that the panels are so effective that the wall behind the radiator is now the coldest.

If I were to do it again I might just cut some shiny and not too bendy sheetmetal to size and save some brain cells (contact cement is nasty).

Is it worth it? I don't have any data but if anyone wants to lend me their FLIR camera I'll post comparison pics. I've read that half the typical radiator's heatloss is radiated and half is convected, so theoretically the panels could increase heat into the room by up to 33%. Considering how easy it is to do I think it is worth it even if in practice the benefit is less than 33%.

mark ransley

The thermal photos really show what everyone looses. Foilfaced foam would help alot. It has to save a measurable percent.