Heat with very high ceilings

[jives]

Hi all;
Looked around the topics but cannot find anything specific to my question. We are building a garage/workshop that when the cars are removed can double as a basketball court. The space is 32 x 42, with 14' sidewalls and raised heel scissor trusses on 8/12 pitch trusses. The peak is about 20'. The building will be used for play and work only part time during the cold months, say 2-3 times per week maximum for 3-4 hours at a time.

Only electric. No radiant floor, no water. Need to heat quick, especially people. I imagine infrared, electric radiant, or "regular" electric with blowers. Estimates put it at about 20,000 watts.

Ideas?

Jeff

 

[tyndall]

No problem to heat 32x42x14 really quick with electric. What part of Florida do you live in?

 

[DekeT]

Why would you need to heat a basketball court in Florida?

 

[jives]

Yeah, so I forgot to say where I am located. Central New York. 60" of snow per year, you get the picture. Good insulation, but two garage doors (insulated), two man doors, 9 windows.

So, I don't want to heat the 20' space, but is that not the benefit of infrared/radiant?

Jeff

 

[bczygan]

Why no radiant floor?

Combine electric radiant floor with gas radiant tubes.

 

[Charles (in GA)]

If you haven't done the math, that 20K watt is 83 amps. That means you will need a couple of heaters on probably 50 amp circuits, with 40 amp heaters on them (code limits electric heat to 60 amp circuits max, with a 48 amp load on them, max). I suspect this will be marginal unless the building is airtight and well insulated.

At 15 cents per Kwh, you are looking at $3.00 per hour or so to run the heaters, and you would require several hours of preheat to make the building usable if cold soaked.

I would seriously look at propane (or nat gas if you have it) radiant tube heaters.

Charles

 

[jives]

Sorry, away for a few days. . . more information. . .

No natural gas in our area. We currently heat/hot water the house with propane, but are moving toward none if we can. We don't want to add another propane device, unless a portable system with its own tank. We are adding solar to the house to account for 100% house electrical, plus the anticipated garage needs. Of course, no solar at night, but the electrical is grid tied and balanced out over the year.

Infloor hydronic radiant heat -- which we have in our house so we are familiar with how it works -- takes too long to heat up and really requires constant heat flow. It still requires either electricity or propane.

So, again, the question. . . If a radiant ceiling heater is 20 feet above the floor, will it still heat the occupants?

Jeff

 

[Gerald O]

...So, again, the question. . . If a radiant ceiling heater is 20 feet above the floor, will it still heat the occupants?

Jeff

Yep. The Sun is 92,960,000 miles away and still warms the Earth's occupants with radiant heat.

Just be aware of the spread of the light pattern emitted by your radiant heat source. The farther away it is the wider the spread. So the same amount of energy covers a wider area which means less energy hitting a given area. Your challenge is to figure out the sizing of the heaters. If they are infrared with reflectors then they will have a specific spread pattern based on the reflector design. You'll need to consult the manufacturers specs.

If you choose to go electric forced air, then you'll need to get that warmed air down low where it will do some good. Since warm air rises it will want to collect up high under that high ceiling. Ceiling fans can be used to help keep it circulating downward.

 

[jives]

Thanks, all. I think infrared can do it, but boy are they expensive. . .

Jeff