I'm wanting to finish my partial basement (300 sq.ft.) to make an extra den living space, but have some low ductwork that I need to move in order to get the right ceiling height.
As you can see in the photos, there are two ducts dropping down from a cold air return that connect to the unit. What I want to do is patch the current connections and take the duct from the front of the return, go straight off the return into the crawl space on the left, follow along the framing in the crawl space, exit in the joists above the bottom of the stairs, and run an elbow down and into the top of the return in the unit (see photos and follow the red line to get an idea of what I am saying). This would be my ideal situation as all ductwork would then be in the joists.
My second option would be to run an elbow at the current unit connection up into the joists and run the ductwork across and through the joists (through each triangle section support) and into the side of the return following its current path. This is less ideal as I would at least have a soffit near the unit where the elbows are...but the ducts would at least be up in the joists.
Any problems with either option? Also, why do they have two ducts coming off of one return going into the unit? Can I use only one duct with either above option? Thanks.