Hello!
I hope it’s clear to everyone considering an answer that radiant heating is a different matter than heating intended to raise the overall room temperature.
Plan: Make a workshop shed usable in winter, which will be used occasionally and then spontaneously for just a few hours.
Problem: Not possible to heat the space, and a chimney is not an option, also not allowed from a building regulation / planning permission perspective.
Approach: Electric heating. Not as room heating, but as mentioned, large-area radiant heating. The room temperature can be as low as 10-15°C (50-59°F) or less. Possibly add solar air heating, but the roof is in an unfavorable position.
Advantages: Very fast response, affordable, simple.
My idea: Use an electric underfloor heating mat and convert a few square meters into radiant panels to hang overhead. I know the radiation angle isn’t ideal for me this way, but otherwise I don’t have enough surface area.
They have about 160 W/m (approximately 49 W/ft), which isn’t much, but the goal is just to prevent freezing.
If I make two strips of 0.5 x 4m (1.6 x 13 ft), that’s 640 W total, which would cost roughly 1 EUR for 6 hours of use. Just as a reference. I could increase the width a bit with an aluminum sheet as a carrier.
What I don’t know is whether this surface area and power output will be sufficient in the right order of magnitude? For now, I would skip any control system; it would be simple enough with a resistive load.
Does anyone have experience with this?
Best regards,
Dirk
I hope it’s clear to everyone considering an answer that radiant heating is a different matter than heating intended to raise the overall room temperature.
Plan: Make a workshop shed usable in winter, which will be used occasionally and then spontaneously for just a few hours.
Problem: Not possible to heat the space, and a chimney is not an option, also not allowed from a building regulation / planning permission perspective.
Approach: Electric heating. Not as room heating, but as mentioned, large-area radiant heating. The room temperature can be as low as 10-15°C (50-59°F) or less. Possibly add solar air heating, but the roof is in an unfavorable position.
Advantages: Very fast response, affordable, simple.
My idea: Use an electric underfloor heating mat and convert a few square meters into radiant panels to hang overhead. I know the radiation angle isn’t ideal for me this way, but otherwise I don’t have enough surface area.
They have about 160 W/m (approximately 49 W/ft), which isn’t much, but the goal is just to prevent freezing.
If I make two strips of 0.5 x 4m (1.6 x 13 ft), that’s 640 W total, which would cost roughly 1 EUR for 6 hours of use. Just as a reference. I could increase the width a bit with an aluminum sheet as a carrier.
What I don’t know is whether this surface area and power output will be sufficient in the right order of magnitude? For now, I would skip any control system; it would be simple enough with a resistive load.
Does anyone have experience with this?
Best regards,
Dirk
N
nordanney24 Oct 2014 07:31Why not simply use an electric fan heater (or a gas heater)? At least it provides real warmth and isn’t such a makeshift solution.
Due to a heating system failure, I tried two years ago to prevent a small unused apartment from freezing completely during severe cold spells by using two simple gas space heaters (each 2.7–4.2 kW). I was only able to maintain a room temperature of about 2–3°C (36–37°F) despite heating for several hours each day. In an uninsulated workshop, you will need a much more powerful setup to heat the entire space, or you might consider heating just the immediate work area, for example with infrared heaters.
BECAUSE a heating system that aims to raise the air temperature in a poorly insulated room is completely pointless.
BECAUSE such a heater would only be somewhat effective at around an estimated 3-5 kW, just to make the room usable – compare the costs, that’s a factor of 5 to 10 higher.
EDIT: see Musketier: apparently not even that…
Also, I can’t constantly stand in the heat flow from something like that because I have to move around about 35 m² (375 ft²), meaning most of the time the device runs uselessly and just heats the neighborhood.
Enough reasons?
A fan heater would be a typical “hardware store, I just want to do it easily no matter the cost” solution in this case.
Regards,
Dirk
BECAUSE such a heater would only be somewhat effective at around an estimated 3-5 kW, just to make the room usable – compare the costs, that’s a factor of 5 to 10 higher.
EDIT: see Musketier: apparently not even that…
Also, I can’t constantly stand in the heat flow from something like that because I have to move around about 35 m² (375 ft²), meaning most of the time the device runs uselessly and just heats the neighborhood.
Enough reasons?
A fan heater would be a typical “hardware store, I just want to do it easily no matter the cost” solution in this case.
Regards,
Dirk
Musketier schrieb:
Due to a heating failure, I tried the year before last to protect a small unused apartment from freezing completely during severe cold with two simple gas radiant heaters (each 2.7-4.2 kW). I couldn’t maintain a room temperature above 2-3°C (36-37°F), despite heating for several hours a day. In an uninsulated workshop, you would need much larger equipment to heat the entire space, or you heat only the immediate work area, for example, with infrared heaters.That’s exactly what I said before: space heating is not effective here. We also use a similar gas device to prevent freezing, but it only feels warm directly in front of it. Kind of like a campfire outdoors. Completely useless in a room over 100 cubic meters.
Your last sentence is exactly what I’m getting at: radiant heating. Terms like “infrared” or “thermal waves” are just jargon; it’s purely about the heat radiation emitted by an object.
This is common in industrial halls because heating thousands of cubic meters of air and contents is really impractical and uneconomical. Gas RADIANT heaters or electric ones (from the 60s: “bathroom heating radiators” with 2 kW and glowing coils), sometimes water-heated with reflectors – typically mounted on the ceiling.
Think of sunlight. The air can be cold, but the radiant heat feels warm.
Think of wall heating (flow temperatures around 25-35°C (77-95°F)). The air temperature can be a few degrees lower, but it still feels comfortable.
Think of a wood stove. “That cozy warmth.”
Best regards,
Dirk
N
nordanney24 Oct 2014 10:57Dirk16 schrieb:
Because a heater that aims only to raise the air temperature in a poorly insulated room makes no sense.
Because such a heater would need an estimated 3–5 kW (3,000–5,000 BTU/h) to make the room reasonably usable—compare the costs; that’s a factor of 5 to 10 higher.
EDIT: see Musketier: apparently not even that…
Besides, I can’t constantly stand in the direct heat flow of something like that, as I have to move around about 35 m² (375 ft²), so most of the time the device runs uselessly and heats the whole neighborhood.
Enough reasons?
A fan heater would be a typical "hardware store, I’ll just do it myself no matter the cost" solution.
Regards,
DirkHow about first insulating/sealing the workshop shed a little for just a few euros? For such a small space, I still think a radiant heater or fan heater—whatever type—probably is the simplest and most cost-effective option. Why put so much effort into a shed that is only used occasionally and spontaneously?