Heating an uninsulated attached barn...

For evening classes over the winter.  Hopefully only for October and November this year.  We've got an attached barn/carriage house on our farm.  Great space, about 500 square feet.  I'd like to use it for my winter classes so that I don't have to pay rent somewhere else.  But it's bitter in there come December/January.  I'm thinking that I might be able to afford insulating and finishing it out after my November class (providing I can fill it).

So what can cozy up a space like that for 3-4 hours at a time?  Ideas?  

Thanks heaps!

Assuming that you have made even a passing attempt to insulate the space,  a wood burner made. from a 55 gallon drum should work for 5 hours.

 Longer term, you made want consider more serious insulation and a rocket mass heater.

We're definitely going to be insulating and hooking it up to our heating system (currently oil forced hot air, but considering going over to heat pump).  I just need an interim solution for a couple of months.

John F Dean wrote:Assuming that you have made even a passing attempt to insulate the space,  a wood burner made. from a 55 gallon drum should work for 5 hours.

 Longer term, you made want consider more serious insulation and a rocket mass heater.

Nissa Gadbois wrote:We're definitely going to be insulating and hooking it up to our heating system (currently oil forced hot air, but considering going over to heat pump).  I just need an interim solution for a couple of months.

John F Dean wrote:Assuming that you have made even a passing attempt to insulate the space,  a wood burner made. from a 55 gallon drum should work for 5 hours.

 Longer term, you made want consider more serious insulation and a rocket mass heater.

Barrel stoves are an inexpensive solution that you could install easily so as a short term solution it would work. Check out the local classifieds/ marketplace for a used stove and chimney, also a good inexpensive solution for a temporary problem.

If you add another room that big to your existing heater it may not work as well, they are often matched to a particular volume,
and certainly need specific pipes to carry any air to a new room.
I would consider a wood heater, they can be  very efficient and if the students are spread around so they
can all get radiant heat it will feel good as well.
How high is the ceiling, it will affect the use of any heater?