Radiant Heat in Ceilings?

Matt · Post by **Matt** » Thu Aug 23, 2018 7:30 pm

I'm researching a mid-century architect of the Pacific Northwest and he often used radiant heating...but in the ceiling! Many of his homes of the 1940s were slab foundations with tinted and waxed surfaces, much like Wright's Usonians, but some had copper pipes weaving through the ceilings.

This seems to me to be counter-intuitive. Would heat really radiate down into the room? Any architects out there have any knowledge of radiant heating systems and why a system in the ceiling would make a sense? Thanks in advance.

DRN · Post by **DRN** » Fri Aug 24, 2018 10:04 am

While it's true hot air rises, infrared heat will radiate outward from its source no matter the direction, and will warm the people and objects within reasonable proximity.

Ceiling radiant heating did have some amount of popularity in some regions and in some house types in the 1940'-1960's. In western PA, there were quite a few houses built with electric resistance heating coils mounted between two layers of 1/4", 3/8", or 1/2" gypsum board (or some combination of them). I never personally experienced a house heated this way, but I have been told by locals from my days in Pittsburgh while in college, that it worked well enough; as good or better than baseboard hydronic, though if mounted on a ceiling above a slab on grade, the floor could be chilly near the edges as one might expect. Installation of this system between a lower and upper floor worked well too, if properly sized and installed.

There are also ready-made mid-century to the present day factory made electric resistance infrared radiant panels (usually steel or aluminum) that are ceiling or upper wall mounted.

The 1949-1951 Lustron all-steel component houses featured hot air channeled above their sheet steel ceilings, providing a ceiling radiant system:
https://www.ohiohistory.org/visit/exhib ... ma-heating

I am not familiar with ceiling mounted hydronic systems other than current day pex tubing mounted between joists with metallic reflector strips to heat the floor above.

Paul Ringstrom · Post by **Paul Ringstrom** » Fri Aug 24, 2018 10:45 am

I built some condominiums in 1979 using electric radiant drywall for the ceilings. Each 4x8 panel had a pigtail coming out of the back that had to be tied together an routed to power and a thermostat.

Since radiant heat travels in all directions it was important to install sufficient insulation above these panels in a one-story building. In a two-story building without the insulation the panels would also heat the floor above.

Some of the advantages were a 1) consistent even heat that was 2) quiet and 3) dustless. You were also able to easily 4) zone each room separately, especially nice when you want a bedroom to be cooler than the living room.

Disadvantages included not being able to screw a plant hanger (or anything else) just anywhere in the ceiling, and the local price of electricity. Illinois had a lot of nuclear plants that kept the cost fairly reasonable. Other areas of the country that have hydro-electric power would also be reasonable. Electric cost by state: https://www.chooseenergy.com/electricit ... -by-state/

Currently, this technology is produced in radiant panel sized to fit in a suspended ceiling grid. This is especially useful along the perimeter of a room that has large expanses of glass. It prevents condensation and water damage to wood trim around windows. Here is one manufacturer: https://indeeco.com/products/wall-ceili ... gL5_PD_BwE

Here is a company that produces hydronic heating & cooling drywall panels: https://radiantcooling.com/messana-radi ... -products/

You also can consult these manufacturers for information about specific products: Enerjoy, Thermaray, Calorique

SDR · Post by **SDR** » Fri Aug 24, 2018 11:01 am

In the first article I read about radiant heating, many years ago, one fact that stood out was that occupants were found to be comfortable with indoor air temperatures notably lower than in conventionally-heated spaces . . .

SDR

Paul Ringstrom · Post by **Paul Ringstrom** » Fri Aug 24, 2018 1:13 pm

SDR wrote:In the first article I read about radiant heating, many years ago, one fact that stood out was that occupants were found to be comfortable with indoor air temperatures notably lower than in conventionally-heated spaces . . .SDR

Yes, this is because the heat is more evenly distributed than a forced-air furnace.

SDR · Post by **SDR** » Fri Aug 24, 2018 3:30 pm

The impression given was that, with warmth absorbed by the clothes and skin, air temperature had less effect on a sense of comfort -- or words to that effect. "It feels like the sun," I think I read . . .

SDR

SDR · Post by **SDR** » Fri Aug 24, 2018 8:16 pm

The assumption in the scheme presented in what I read is that radiant panels would be directed toward specific areas of an enclosed space -- seating, work stations,
etc -- rather than blanketing the space. This would presumably lead to lower heating costs, compared to maintaining a given air temperature in that space.

SDR

Matt · Post by **Matt** » Fri Aug 24, 2018 10:58 pm

Thanks for the info. The houses I'm researching had copper pipes in the ceiling. These were often shed roof homes so no attic. The heat was often by oil burner and I understand there could be some noise associated with the heat coming on as the pipes vibrated. One example of this architects work had pipes in both ceiling and floor.

Roderick Grant · Post by **Roderick Grant** » Sat Aug 25, 2018 10:44 am

Matt, this sounds like an architect whose last name is Brown ... can't think offhand of his first name. Is that right?

History of heating may be interesting, but with systems in new houses tending to provide both heating and cooling, it would seem forced air will win out.

DRN · Post by **DRN** » Sat Aug 25, 2018 12:48 pm

In a house, I would only heat with forced air as a last resort. Radiant floor heat if at all possible, baseboard hydronic otherwise. Air for cooling only.

SDR · Post by **SDR** » Sat Aug 25, 2018 1:11 pm

Manufacturers' (and trades' ?) lobbies have mandated much of current construction code. Where is the constituency for geothermal ? If I were king, new construction
would have a mandated geothermal system for heating and/or cooling assist, wherever practical -- which I would assume would be almost everywhere ?

SDR

Paul Ringstrom · Post by **Paul Ringstrom** » Sat Aug 25, 2018 5:52 pm

Earthlinked Technology is an alternative way to do geothermal. Especially good for smaller lots: http://earthlinked.com

SDR · Post by **SDR** » Sat Aug 25, 2018 6:16 pm

Thanks, Paul. I don't find specifics on their system; can you fill me in on how it's done ? I assume something is bored or trenched into the ground . . .

SDR

Paul Ringstrom · Post by **Paul Ringstrom** » Sat Aug 25, 2018 9:31 pm

This is the biggest advantage of this particular system:

From their website:

Minimally Invasive Installation Options
EarthLinked Geothermal Renewable Energy Systems are compact and require a smaller amount of yard space to install than any other system. They can be installed in any home, regardless of property size. We offer nine different earth loop system configurations, which allow us the flexibility to install geothermal solutions in both larger and smaller properties. Diagonal earth loop configurations can be installed in areas as small as three feet in diameter. Plus, because the technology is placed underground, you will have less equipment inside your home or visible on your property.

also: http://earthlinked.com/how-it-works-the ... n-process/

Matt · Post by **Matt** » Sat Aug 25, 2018 9:46 pm

I'm researching Paul Hayden Kirk. Most of his homes of the 1940s had this odd system of radiant heat is cielings or floor or both. He did one of the Revere Quality Houses and that used a lot of copper pipe which no doubt pleased the Revere Copper and Brass company. I'm not sure if he was copying Wright or if this system had broad appeal.

Where did Wright pick up on this idea? His systems were steel imbedded in the concrete....do I have that right?