Quote Originally Posted by atb123 View Post
Hi, full disclosure, I have virtually no HVAC experience...trying to learn!

I am currently working on the layout of a new construction house with my architect.
The last house I built ended up with soffits everywhere, so I'm trying to be more careful this time around.

The house is a single family city rowhome. 2600sqft, 4 stories, 38' high.
{ I'm planning to do dual zone HVAC. }
__ " ___ " ___ _ to use 2 HVAC systems

In an ideal world. I'd have both inside units located in the basement.
One unit would service the basement, first floor and second floor (roughly 1600sqft of area).
The second unit would service the third and fourth floors ( Roughly 1300 sq.ft. of area).

I attached a rough schematic of the basement layout.
The issue I'm having is that I can't run the trunk the full length of the house because
there's an inaccessible area of the basement.
What I'd like to do is have two elbows in both trunks to allow them to "climb"
from the basement to the first floor where
I would then have a soffit in the garage that would allow for branches to reach everywhere.
The bottom wall in the diagram will be framed with 2x6s.

The maximum reach from the basement furnace to the top floor is roughly a 35' run
(assuming I do floor registers on the 4th floor).

If I can't do the elbows in the trunks, I'll have to move the furnaces up to the 1st floor.
There's also a spot on the 3rd floor where I can locate the 2nd furnace if that positioning helps things.

Any insight would be very helpful. I'm around 5 months away from needing an HVAC contractor,
but I would love to have everything mapped out now! Thanks so much for the help!
...Seems like a total of FIVE STORIES

18' x 40' = _______ 720 SQ FEET __ Ref. Post # 12
Floors 1, 2, 3, & 4 __ * 4
________________ 2,880 SQ FEET
Basement _______ ~ 400
Total ___________ 3,280 Sq Feet.

Why is 2,600 sqft mentioned?

There should be a system on the third floor with 2 zones.
__ " ___ " __ " _ " __ " _ in the basement with 3 zones.

What will be the designated A.C.H. Natural in the house specifications?
__ i.e. < 0.2