Thanks for the response Glenn, The forge would be vented on the north wall which would be the proper side for the majority of the wind that we get here up in Ontario. I have been talking to a few smiths and they are unsure how well it would work. I am actually trying to figure out which type of forge to go with, I understand the ease of propane but I do a lot of art pieces and having the large forge area of a coal forge is something that appeals to me. Good point about the windows upstairs, I guess it will be something that will have to be closed when the forge is running. I just talked to a HVAC guy and he told me that the furnace blower will be more than adequate for sucking up the exhaust... almost too much he warned!
DO you think its worth the try?
Thanks, The HVAC guy did recommend a belt driven blower and finding a sealed motor. He mentioned it may not be needed but it might extend the life a fair bit.