View Full Version : Heating size question

02-19-2007, 07:16 PM
I have no clue as to the formulas of heating, how much radiator per space.

In the new kitchen we are putting up:
[approx 360 sq ft, 12' high ceiling, insulated well (R-30 in ceiling and R-13 in walls) minimal window load (11sq ft of low 'e' and one 6' low 'e' patio door)]

I'm planning on 2 - 2' radiators approx 3' tall (if I can find them) to heat the area on it's on zone. Powered by a 70,000 BTU boiler using 3/4" copper trunk lines.

Basic question, is that enough? I don't have alot of wall space for radiators (that is literally all I have available.

Thanks in advance all, you guys are great with all your help!

Mike in NJ

02-19-2007, 07:53 PM
You might want to consider in-floor radiant heat...much nicer, and it doesn't take up wall space. The amount of heat you can get out of the radiator depends on the area, the incoming water temperature, and the flow. The manufacturer's specs should give you that info.

If you search around, you can probably find a heat load calculator application on the web and figure out what amount of heat you need in that room. WIth the high ceilings, a radiant floor will make it much more comfortable at the same air temperature.

Then, match the radiator size to the required heat load.

Bill Arden
02-19-2007, 07:55 PM
First you need to know how cold it gets.

Heating requirements vary wildly based on other factors.

For example my new (windowless) garage is 900sq feet and takes less than 1/4 the heating needed than my old 850 sq foot house.

It's also a matter of if you plan on keeping the house heated or plan on using setback thermostats.

You can also increase the heating ability by adding fans to a radiator and they actually make small fan based units.

02-19-2007, 07:57 PM
The heating load was calculated at 15,000 BTU's using an online heat calculator

02-20-2007, 03:45 AM
That sounds a bit on the high side. My whole house of 2600 sq ft has a 75,000 BTU output furnace, which easily copes with -10 design temp and actual temps in the minus teens. It's late 1980's well insulated, but no more than you have. Your design temp should pobably be zero or +10.