Baseboards are convection heaters that are designed to heat the air and provide negligible radiant heat. Most wood stoves and gas stoves provide both, with radiant heat from the front and glass, but most of the heating is of the air through convection.

The chimney is brick, on the exterior of the home. I've read a lot about that not being an ideal system, but it's what we have. The furnace tech is currently in the basement for the 3rd time, and is talking about installing an exhaust fan on the exhaust pipe before it hits the chimney to help push the exhaust out. He says the draft is "crap." He also mentioned that the newer furnaces (which this is) don't produce enough heat to induce a strong draft, which I have heard about as well. We did have the chimney inspected - twice. And both inspectors said that it's fine. This is why the problem has been so frustrating. Everyone is telling us everything is fine, and it clearly isn't. Should we try the fan?

Stick with the steam that is the most confort as far as its not dry heat like a forced hot air. Why anyone would go to forced out air is just taking the cheap way out. A hot coil in an air handler will work better. Also have e you thought of radiant floor system at all or off the return of your boiler you can have a circulaing pump and add baseboard to the new room. if 75 gallon water heater isn't cutting it you may want to try a tankless water heater. Don't go with forced hot air you wont be happy. Here would be my options that you can run by a good plumber. 1 tankless water heater to do radiant floor or coil on a air handler, with a heat exchanger you can also do domestic water and never worry about hot water. the neg side about this is tankles has to be on a maintnace program for scalling and general PM. 2 put a B&G pump on the return of your steamn boiler and use that hot water to do a basboard or new radiaters in your new addition. for your a/c I would go witgh a ductless systeem if its only one big room. here are the three manufactures I would go with 1. tankless I would go with takagi ( make sure its sized correctly) 2. air handler I would go with first company. 3. fujutsi if you where using a ductless. If it was my house I would use high baseboard and heat it only to 140 degrees stick that on a tankless water heater and get my domestic hot water thrue that also. or radiant floor instead of baseboard. Use the fujitsu unit for the a/c of the house.

THANK YOU so much for your responses. Jake: I totally forgot about the fact that we need to update/upgrade our electric panel for our 1976-house. So any electric option is not viable. asolo: I read a couple of your other posts about tankless; I'm very convinced not to do tankless. joeplumb: our furnace (boiler) is designed to heat up the 1st floor, 2nd floor, and an indirect water heater. so to get a direct water, we'd wouldn't be utilizing our furnace optimally. We're in MA: very high gas and oil and electric prices. And forecasted to be worst this winter. sigh. We went with the SuperStor indirect stainless steel water heater, which is supposed to work great w/ well water. Yay for hot showers again. again, thank you very much.