Radiant ceiling

Gordy

I married this one when I bought the house. My Granparents built it in 1952. Its been performing ever since.

Its copper tubing which is fastened to the backerboard then the brown coat goes on followed by the top coat, about 1" thick. Has quick response with a little thermal mass kicker NICE!

Gordy

Big Will

Radiant ceiling with aluminum panels

I have never done this before but with radiant floor using the panels I get about 80 deg floor with 135-155 deg water depending on the floor thickness/covering. I looked at the R-values and 3/4 hardwood over 3/4 ply is R-2.2 but 5/8 rock is about r-.5. With this in mind I would think the ceiling surface temp would be higher with the same water temp. However I cant secure the plate to the drywall the way I can to the sub-floor. I would expect this to drop the surface temp a little. The space I am heating with the radiant ceiling is the highest load (Finished basement) so I will need a higher surface tempto meet the load. I could set it up to run of the domestic hot water priority to get a higher temp but would rather keep the temps as low as posible. Running numbers is one thing but seing it run is another.

john_215

You might be using the wrong numbers. As I understand it the radiant energy off the plates in a downward direction is less--the r val against a downward flow of heat is more.

hot_rod

As long

as the sheetrock is in good contact with the rock the transfer will be fine. No need to attach to the rock.

My ceiling has exposed transfer plates, to my wife's chagrin (sp) It works fine, quick recovery. My plates do squirm a bit as they are just fastened into the rock in some areas, where I missed the ceiling joists. A bit of ticking sometimes.

Yes, with no foot traffic, you can run much higher surface temperatures thus higher btu/ square foot output.

I've heard 140F is about as warm as you want to expose sheetrock to, under continous conditions. About the same as gypcrete, I suppose.

I think those foam/ aluminum Roth panels would be great for ceiling. Solid aluminum and a bit of additional r-value and some movement allowance in the foam.

hr

CMadatMe

Radiant Ceiling

Maybe this attchement will help you out. Best of luck

CMadatMe

Radiant Ceiling

I've attached a nice explanation on how to design it. Hopefully is will help you out and anwser your questions. Best of Luck.

Big Will

They don't make that plate anymore is my under standing but that is the method I intend to use. My biggest question is what surface temps you get with different water temps. I know that I can run the ceiling higher but I would rather not make a additional temperature loop in the mech. room. As it is i need 180 for my domestic and five fan coils and depending on the outdoor reset 95-150 for my radiant floors. With staple up and thermal board. i would like to use the same loop and pump for the radiant ceiling. If the same water temp I am using for the floors will give me a slightly higher surface temp for the ceiling (lower R-value with Sheetrock) I am set. Just looking for results in installs that have been done.

Gordy

Temps

How high are your ceilings, and what is the Btu requirment for output to heat the space? Tube spacing yet to be determined?

I have radiant ceiling of a different design. My tubing is in the plaster, I never see supply temps to the panels of more than 110*-115*. That translates to a surface temp of about 83*-88* It all depends on the demand. Design day -10* you are looking at 115* supply 100* return. Panels at 86* for a heating cycle.


Gordy

Big Will

That makes sense if it is actually in the plaster you cant ask for better contact than that. How did you install it to make that work?

Big Will

I thought you might say that. I was hopping their was a method I didn't know about. If I could get performance like that with the aluminum panels I would be set. I was thinking about what the GC would say if I asked him to do a lath in plaster lid for me. I think if he just laughed I would be lucky.

Gordy

Performance

I think your performance could approach or be equal to mine with plates.

My tubing centers are 6-8 inches. The whole ceiling is used in the house not just parts of it. Why not use a sleeper style install (like the wisbro manual) on the ceiling unless its already up. Then you are going to get good plate contact.


Gordy

Big Will

I would prefer the sleeper method. They don't want to loose any ceiling height though. I may be able to talk them into it we will see. The ceilings are already 7 1/2 feet but loosing 3/4" is all I'm asking for.

[Deleted User]

is there a rule of thumb for low ceiling hgt and radiant ceilings? my basement would be 7ft finished.

Unknown

keep your surface temps low.. say 85 or so.. when you are low to prevent 'hot head'. at 1.2 to 1.4 BTUs/sq ft per dt surface temp to room temp, that's something like 18 to 21 BTUs/sq ft of coverage, something like 105 to 110 degree water requirements. Insulate over the the assembly.

Unknown

lots of light gauge plates out there. I like PAP tubing to avoid expansion.

general recommendation is not to run more than 120 with sheetrock.

jd_13

thanks!

Pinball

Just curious.

will ultra fin work in this situation?

It would make the install easier, and no mixing required.

just a thought.

Unknown

It would be pretty hard to guess what the temperature of the bottom of a heated joist bay would be. Certainly it would be a low output.

Unknown

why not just install

Why not just install the old and tried method? Cast iron base boards?
No lost of space height or room. 2nd best heat/comfort to have.

Unknown

higher temp, more expensive, takes up wall space, not as comfortable as a radiant ceiling in most cases. if you're strapping a ceiling anyway (they all do up here in maine) there is no loss of ceiling height either.

Radiant ceiling is a great method in many applications.

Marc_22

raupanel

use raupanel. the 5/8" sleepers become your strapping for sheetrock.