Need basement HVAC Help

[drumz]

First off please, my heater is capable of handling twice the entire 1500 sf house including the basement which it originally heated; remodeled 4 years ago and added new intake, trunk, simplifying runs, tying old with new but same plant (20 yrs). I'm trying to figure out basically 2 things, reducing the amount of drop up and venting the entire room which will have a bathroom. The video shows the trunk and the runs to the left and at the first 90 which then 90's up to the kitchen above.
1) Can I get that run up to the kitchen tighter to the ceiling?
2) I need to heat the bathroom area and the rest of the room. I was thinking of adding a vent to the trunk but wasn't sure about where to put one in the bathroom. I'm building a soffit and plan on adding a fan to that so maybe I should put the vent in-between the 2 90's?
Any advice is appreciated.
Basement video

 

[Sparky617]

In my basement I built a soffit all around the perimeter of the basement to handle the ducts. I fortunately have nearly 10' ceilings so the loss of a foot around the perimeter wasn't a problem. I also dropped the whole ceiling in a couple of places to handle the ducts and plumbing. In my basement I added a new unit for the basement a ducted mini-split system. My ceiling is pretty full of ducts between the first floor unit duct work and the basement ductwork. The perimeter soffit has some duct work in it along the back wall above the windows and along the wall with the stairs.

 

[drumz]

Nice job!
My ceiling is 83" high but around the soffits it is 78" so I'm very limited height wise so want to see if I can get that one run up 2" higher because it sits down at 76" and the bathroom sink will be under that part of it so it's workable but I also have to put the exhaust fan in there and it was also where I was thinking of putting a heater vent. I was also thinking about doing a vertical run down to the floor in that area but not sure if the air from the heater will go down it.

 

[Sparky617]

With your sub-8' ceilings I'd try to tuck as much around the perimeter as possible and if you have to drop it do a soffit. I went with a consistent 1'x1' soffit around the perimeter except for the one section that was full of ducts and other obstructions.

 

[Sparky617]

Here's a thread I posted on the project with more pictures, and some of the same posted here.

https://www.houserepairtalk.com/threads/basement-project.31451/

 

[Sparky617]

On my walkout, I had a 2x8 sill plate with a 2x4 wall built on top. Rather than try to figure out how to handle the 3.5" of sill plate in the finished space I just doubled up with above ground exterior wall and made it 7" thick. Giving up the square footage seemed like the easiest solution to the problem. I really didn't want to raise the floor up because that would throw the stair raisers off for the first step. Given our mild climate I really didn't need to worry about heating the floors, or adding more insulation to them. Though heated floors would be epic in the winter.

 

[drumz]

Thanks for the advent
Any vent tips are appreciated

 

[Sparky617]

I'm not a fan of suspended ceilings and if you use one you'll lose a bit more headroom. When I did my basement (still doing actually) I went with a drywall ceiling and was able to keep the obstructions limited giving it a clean look without a bunch of boxed out areas to cover mechanicals and other obstructions. If I ever need to access the space above the ceiling I can always cut a hole and patch. The soffit I built gives me a nice chase around the room to handle future and yet unknown improvements. I tried to anticipate many different uses for the space by me or a future owner. I made provisions to allow future use as a home theater even though I have no current plans to make one. With just my wife and I here now I don't need another room to watch TV in.