Branching ductwork from a wall stack
While I will most likely seek installation help from professionals, if I may,
I would like to ask some ductwork installation questions so I am better educated when seeking a bid. I have recently purchased a small two story home (1200 sq ft) in western PA, circa 1910. The heating system was compromised quite badly and much of the structure was heated by a combination of electric strip heat and a wood stove. I am considering adding a gas forced air system.
First floor suply ductwork and the first floor return air don't appear to be much of an issue. Of course there is nothing available to the second floor which is approximately 500 sq ft. I can run a stack within a closet through the first floor and even into the attic if needed. I think I have a space about 10" by 24" available for the stack. There are two small bedrooms and a bath on the second floor.
A few questions: (1) Considering heating is of primary concern in western PA, I've always heard that heavier heating needs suggest that floor vents are preferred over ceiling vents. Given that it would be easier to run insulated ductwork through the attic, does this ease of installation give ceiling vents the nod? (2) This next question demonstrates my ignorance. Just how does one branch flexible ducts off the top of a wall stack? I'm assuming I will have as many as 4-5 flexible ducts. (3) Can the only proposed cold air return to the first floor be extended to the second floor and simply opened there (one return stack - two vents, one on each floor).
Many, many thanks.