You may be able to add a zone. What is the size of the furnace? Do you know if it is a single stage or have a variable speed blower. A model number would help.

If the furnace is a single stage, the problem is you can't force all the air into one zone. You will need some type of bypass. You need a HVAC contractor to evaluate the furnace and duct work and see if zoning is feasible.

Do you really want to add a zone, or do you want more heat in the bedroom? Has the duct system been checked for obstructions and leaks? What are the relative costs of heating with propane and electricity in your area?

If everything is OK and you just want more heat to that room, add duct to the room or take out the existing one and add a larger duct.

Mike it's an Armstrong AIR Ultra SX 80. I think it's a single stage. Thanks for the advice.

ionized, I only keep the thermostat at 68 and the downstairs bedroom is at 60 at best. I'll check the duct system but think it's ok as far as no blockages etc. Thanks for the info.