Provided the furnace has enough power to heat the additional room (have to check w/the company I purchased it from on this) what would the approximate cost be to add an extra vent in a room that currently has no heat?

Hi, margog85!

Are you asking the question based upon someone else doing it, or doing it yourself, please?

It might not cost much at all if you do things yourself! My garage never had any heat from the furnace out to it. What I did was to cut out sections of ducts from the furnace in my basement; install ducts into those places that I had cut out, with places on them where I could place additional ducts to run some other lines.

Wasn't hard and didn't cost all that much. But, I didn't have to really cut through anything to add the additional ductwork.

Would it be necessary to have to cut through anything to add any ductwork?

Thanks!

I was actually looking to possibly hire someone else to do it. I just got a new furnace installed and don't want to do anything that could potentially mess it up after spending that much money on it!

I don't know what I'm doing at all, and don't want to take that kind of risk!

If the square footage of the room in question wasn't factored into the heat load/heat loss of your home then you might run into some issues and not just with the heat.