Hello,

I have a small cottage (construction in progress) where living during
the weekends; there is one room, 16' x 24' with a cathedral ceiling,
16' high at the top.
Inside this, is an open (no walls) mezzanine (as bedroom) 16' x 12'.
For heating I have installed a wood stove and a ceiling fan for air
circulation.
As a second option for heating (mainly during the night or when not
in), I did install baseboards for heating this room with a total power
of 4000 watts.
The sizing formula for baseboards, I found from web, is:
"Required power (in watts) for baseboards is calculated by multiplying
the number of square feet in a given room by 10."
Thus a 16 x 24 ft. room (380 sq. ft) will require 3,840 watts of power
(380 x 10).
I am using one programmable thermostat which supports 4000 watts.
I am wondering if this is enough, considering there is a cathedral
ceiling and living in areas where in winter is cold (Canada).
If I have to add more heating elements, is it better to add portable
heaters or another thermostat with new baseboards?
How many watts should I add for heating elements?

Thank you, Chris

On Mar 1, 8:18?am, "Chris" wrote:
Hello,

I have a small cottage (construction in progress) where living during
the weekends; there is one room, 16' x 24' with a cathedral ceiling,
16' high at the top.
Inside this, is an open (no walls) mezzanine (as bedroom) 16' x 12'.
For heating I have installed a wood stove and a ceiling fan for air
circulation.
As a second option for heating (mainly during the night or when not
in), I did install baseboards for heating this room with a total power
of 4000 watts.
The sizing formula for baseboards, I found from web, is:
"Required power (in watts) for baseboards is calculated by multiplying
the number of square feet in a given room by 10."
Thus a 16 x 24 ft. room (380 sq. ft) will require 3,840 watts of power
(380 x 10).
I am using one programmable thermostat which supports 4000 watts.
I am wondering if this is enough, considering there is a cathedral
ceiling and living in areas where in winter is cold (Canada).
If I have to add more heating elements, is it better to add portable
heaters or another thermostat with new baseboards?
How many watts should I add for heating elements?

Thank you, Chris

The cathedral cieling is a killer, I would of gone with radiant floor
heat, puts heat where you are.

in cathedral cieling ALL heat goes to peak. cieling fan helps but
creatyes cool draft.

4000 watts totally undersized, might be lucky to keep building barely
above freezing in zero weather.

so how thick are the walls? what sort of insulation? closed cell foam
R6 PER INCH elminates drafts too.

On Mar 1, 7:25 am, " wrote:
On Mar 1, 8:18?am, "Chris" wrote:



Hello,

I have a small cottage (construction in progress) where living during
the weekends; there is one room, 16' x 24' with a cathedral ceiling,
16' high at the top.
Inside this, is an open (no walls) mezzanine (as bedroom) 16' x 12'.
For heating I have installed a wood stove and a ceiling fan for air
circulation.
As a second option for heating (mainly during the night or when not
in), I did install baseboards for heating this room with a total power
of 4000 watts.
The sizing formula for baseboards, I found from web, is:
"Required power (in watts) for baseboards is calculated by multiplying
the number of square feet in a given room by 10."
Thus a 16 x 24 ft. room (380 sq. ft) will require 3,840 watts of power
(380 x 10).
I am using one programmable thermostat which supports 4000 watts.
I am wondering if this is enough, considering there is a cathedral
ceiling and living in areas where in winter is cold (Canada).
If I have to add more heating elements, is it better to add portable
heaters or another thermostat with new baseboards?
How many watts should I add for heating elements?

Thank you, Chris

The cathedral cieling is a killer, I would of gone with radiant floor
heat, puts heat where you are.

in cathedral cieling ALL heat goes to peak. cieling fan helps but
creatyes cool draft.

4000 watts totally undersized, might be lucky to keep building barely
above freezing in zero weather.

so how thick are the walls? what sort of insulation? closed cell foam
R6 PER INCH elminates drafts too.

Question - Did you mean electric radiant floor heat, like we often
seen under tile? Since it is a cabin, I am guessing that the OP might
not always have the heat on, so any hydronic system would freeze.
Just wondering.

JK

"Chris" wrote in message
oups.com...
Hello,

I have a small cottage (construction in progress) where living during
the weekends; there is one room, 16' x 24' with a cathedral ceiling,
16' high at the top.

I frankly don't know anything about HVAC, but I have some experiences that
might help you. I am assuming you will not be heating it when you are not
there. If you are rich enough to do that, then you can just put in all the
heaters you want and not worry about it.

Two weeks ago we went away for the weekend and I turned the heat down to 55.
It was about 25 out.
It took 8 hours to get back to 72. Unless your heating is way oversized,
you won't have it warm until you are ready to leave.

My cottage is about the same size as yours, but the ceiling peaks at 12'.
The insulation is not good, so maybe they are about equal. I can get it
about 25 degrees over outside temperature with my wood stove. With better
windows and insulation I am sure I could do better, but getting it actually
warm on a cold day would be a challenge for a wood stove.

And finally, my cottage takes about 3 hours to winterize for subfreezing
weather, and maybe an hour to bring back. That could be improved with
better design, but there is still alot to do. Make sure you know what you
are doing.

Chris wrote:
Hello,

I have a small cottage (construction in progress) where living during
the weekends; there is one room, 16' x 24' with a cathedral ceiling,
16' high at the top.
Inside this, is an open (no walls) mezzanine (as bedroom) 16' x 12'.
For heating I have installed a wood stove and a ceiling fan for air
circulation.
As a second option for heating (mainly during the night or when not
in), I did install baseboards for heating this room with a total power
of 4000 watts.
The sizing formula for baseboards, I found from web, is:
"Required power (in watts) for baseboards is calculated by multiplying
the number of square feet in a given room by 10."
Thus a 16 x 24 ft. room (380 sq. ft) will require 3,840 watts of power
(380 x 10).
I am using one programmable thermostat which supports 4000 watts.
I am wondering if this is enough, considering there is a cathedral
ceiling and living in areas where in winter is cold (Canada).
If I have to add more heating elements, is it better to add portable
heaters or another thermostat with new baseboards?
How many watts should I add for heating elements?

Thank you, Chris

There is a flaw in your calculations because they only account for square
footage of what? There has to be a volume associated with it so that the
calcs indicate the real amount of air to heat. The "10" is apparently the
default modifier for volume, but ... for what temperature rise?

If you're in a cool climate, not cold, then it might be barely enough but
it'll be incredibly slow to heat with. If the temps go below freezing and
especially far below, you'll hardly even know that heat source is working.
Your fan will only create cold drafts for several hours.

So, you need to look into the temperature "rise" you need (20, 40, 60
degrees, etc) that you need, plus calculate it on the actual volume of the
area to be heated.

Btu/hr is the "magic" number you're looking for if you want to do some
research.

I'll be honest with you, I would consider a mobil-home sized used forced air
furnace for this application, assuming you can get fuel oil to a tank for
it. Anything from 55,000 to say 85,000 btu output should suffice, you'll
have to size it, and you'll get a lot faster heat rise than with electric.
The fans in a forced air system also work to help clean the air of dust
etc.. If you can get hold of one from a trailer they're small in size and
easy to build into an alcove and meet code with. I'm just thinking of hte
cost of electricity to heat with vs oil or gas. It wouldn't even require a
lot of heating ducts for such an arrangement.

HTH
Pop`

Hi Chris,

I have a small cottage (construction in progress) where living during
the weekends; there is one room, 16' x 24' with a cathedral ceiling,
16' high at the top.
Inside this, is an open (no walls) mezzanine (as bedroom) 16' x 12'.
For heating I have installed a wood stove and a ceiling fan for air
circulation.
As a second option for heating (mainly during the night or when not
in), I did install baseboards for heating this room with a total power
of 4000 watts.

We heat our home with electric wall heaters made by King Electric.

They have a formula that says 12.5 watts per foot if you have little
insulation, 10 watts per foot with average insulation (R11 walls, R19
ceiling), or 8 watts per foot fully insulated (R19 walls, R38 ceilings).

Those calculations are based on 8 foot ceilings. They recommend the
wattage be increased 25% for every 2 feet increase in ceiling height
above 8'.

In theory, that should work out to 7680 watts for your 384 square feet
and 16' ceilings. But, King Electric also recommends a maximum of 15
watts per square foot which would work out to 5760 watts. So, somewhere
in between those two numbers would probably be fine.

In my case, we have 14 foot vaulted ceilings, R21 walls, R30 ceilings,
R30 in the floors, and double pane windows. I used the 10 watts per
square foot formula, and our house stays nice and warm. The heaters only
run occasionally, in fact, we don't even use the heaters in our laundry
and bathrooms. They stay plenty warm just from the heat in the other
rooms. So in practice, we use 12750 watts to heat our 1456 square foot
home, or about 8.8 watts per foot.

For the sake of comparison, I use a 4000 watt heater in my 24'x28' garage
with a 10 foot ceiling (R19 walls and ceiling). That's about 3000 watts
less than I should have. It runs constantly just to keep up, and never
really gets much above 60. It's comfortable for working in, but it
wouldn't be enough wattage for a living space. I keep saying I'm going to
add a second heater, but I only use the heater when I'm out there working
so I haven't bothered with it.

If your cottage is well insulated, you might want to add another 1000
watts or so, to compensate for the higher ceiling. Or, you might wait and
see how your current 4000 watts works out and add more heat later if it
is needed. Electric heaters are fairly easy to add on when needed (I just
installed three electric wall heaters in my in-laws 100 year old house).
There's no reason to install extra heaters if you don't need them.

Anthony

On Mar 1, 8:18 am, "Chris" wrote:
Hello,

I have a small cottage (construction in progress) where living during
the weekends; there is one room, 16' x 24' with a cathedral ceiling,
16' high at the top.
Inside this, is an open (no walls) mezzanine (as bedroom) 16' x 12'.
For heating I have installed a wood stove and a ceiling fan for air
circulation.
As a second option for heating (mainly during the night or when not
in), I did install baseboards for heating this room with a total power
of 4000 watts.
The sizing formula for baseboards, I found from web, is:
"Required power (in watts) for baseboards is calculated by multiplying
the number of square feet in a given room by 10."
Thus a 16 x 24 ft. room (380 sq. ft) will require 3,840 watts of power
(380 x 10).
I am using one programmable thermostat which supports 4000 watts.
I am wondering if this is enough, considering there is a cathedral
ceiling and living in areas where in winter is cold (Canada).
If I have to add more heating elements, is it better to add portable
heaters or another thermostat with new baseboards?
How many watts should I add for heating elements?

Thank you, Chris

My suggestion would be to go to this web site and pose your question
http://heatinghelp.com/

There are a lot of very good heating guys there.

-paul

On 1 Mar 2007 05:18:18 -0800, "Chris" wrote:


I am using one programmable thermostat which supports 4000 watts.

No actual experience with anything unusual, but I"m surprised to hear
there would be a limit on the wattage suppported by a thermostat.
After all, all it does it turn on power to a relay. If the relay drew
too much power (which seems unlikey) one could use an acceptable
intermediate relay to provide power to all the other relays/

I am wondering if this is enough, considering there is a cathedral
ceiling and living in areas where in winter is cold (Canada).
If I have to add more heating elements, is it better to add portable
heaters or another thermostat with new baseboards?

ISTM, it seems to me, that two thermostats can be aproblem if they
aren't set to the same or almost the same temperaturee. At least it
would be a problem if you want to use both systems. If you by accident
set one to a higher temp, it will go on first and might keep the temp
at the other thermostat from ever getting cold enough to turn on.
That might be fully acceptable, but might not be if the first source
of heat costs more than the other, or other reason.

OTOH, if one thermostat is higher and so gets warmer air, it might run
all the time and keep the lower heat source from running, even if set
to the same temperature.

I don't know what is recoemmended.
How many watts should I add for heating elements?

Thank you, Chris

No actual experience with anything unusual, but I"m surprised to hear
there would be a limit on the wattage suppported by a thermostat.
After all, all it does it turn on power to a relay. If the relay drew

That's not always true for electric heat. Some 240V electric heaters
pull line voltage through the thermostat.

too much power (which seems unlikey) one could use an acceptable
intermediate relay to provide power to all the other relays/

On Thu, 01 Mar 2007 14:51:24 -0500, Goedjn wrote:


No actual experience with anything unusual, but I"m surprised to hear
there would be a limit on the wattage suppported by a thermostat.
After all, all it does it turn on power to a relay. If the relay drew

That's not always true for electric heat. Some 240V electric heaters
pull line voltage through the thermostat.

240 volts up on the wall, or near my shoes, where I might touch it? I
guess I won't be taking apart any electric heat thermostats from now
on.

OK. Didn't know that. One could still use that line voltaghe to
power two other relays. Or to power 3995 watts worth of heat and a
relay to turn on the rest of the heat.

too much power (which seems unlikey) one could use an acceptable
intermediate relay to provide power to all the other relays/

I'm surprised to hear there would be a limit on the wattage
suppported by a thermostat. After all, all it does it turn
on power to a relay.

There are two kinds of thermostats.

"Low Voltage", the most common type that typically run on 24vac and use a
relay to control the actual heater.

and

"Line Voltage", these connect between the electrical source (120V or 240V)
and the heater.

We have line voltage digital thermostats in our house, and the contacts are
limited to 22 amps.

I used 12/2 wire which can support 20 amps, but it has to be "derated" with
electrical heat. So, I kept my total load on each thermostat under 3840
watts (16 amps).

I could have used 10/2 wire to control more wattage with the thermostat,
but I prefer not to max out the circuit or thermostat, and I didn't need to
anyway. We have individual heaters in each room with separate thermostats,
on their own circuits. Most are 2250 watts or less, except for our
kitchen/dining area where I have 3750 watts.

Anthony

On Mar 1, 8:18 am, "Chris" wrote:
Hello,

I have a smallcottage(construction in progress) where living during
the weekends; there is one room, 16' x 24' with a cathedral ceiling,
16' high at the top.
Inside this, is an open (no walls) mezzanine (as bedroom) 16' x 12'.
ForheatingI have installed a wood stove and a ceiling fan for air
circulation.
As a second option forheating(mainly during the night or when not
in), I did install baseboards forheatingthis room with a total power
of 4000 watts.
The sizing formula for baseboards, I found from web, is:
"Required power (in watts) for baseboards is calculated by multiplying
the number of square feet in a given room by 10."
Thus a 16 x 24 ft. room (380 sq. ft) will require 3,840 watts of power
(380 x 10).
I am using one programmable thermostat which supports 4000 watts.
I am wondering if this is enough, considering there is a cathedral
ceiling and living in areas where in winter is cold (Canada).
If I have to add moreheatingelements, is it better to add portable
heaters or another thermostat with new baseboards?
How many watts should I add forheatingelements?

Thank you, Chris

Thanks for answers.
I think I will add more insulation only on the peak region, making the
part of the ceil as horizontal in that area. I hope this will help
The walls are insulated with R28 fiber glass. The floor with R31.
I will keep the 4000 watts baseboard with one programmable thermostat,
as long as they are the second source of heating. The main one is the
wood stove and I was able to increase the temperature from -5 C to 15
C in one hour.
The baseboard will be used for keeping the temperature during the
night and when not in (to a minimum +5 C).
I will use portable heaters (aerotherme) if need more and fast heat. I
already have 2 of them.
What do you think?
Thanks again,
Chris