Have you thought about in-floor radiant?

Separate zones help keep the temperatures consistent throughout the house. It also allows to have one zone warmer or cooler then the rest of the house. Zones may save some operating costs, but they are small. It is unlikely you will ever get a return on investment.

It is possible to lock out the heat strips by installing a thermostat with an outside temperature sensor. This avoids the heat strips from turning on if you use a set back.

I don't understand the logic about having a smaller return in the master bedroom/den area. The return has to be sized for the amount of air the zone will use. If it is too small then it will be have more noise.

If you are going to have 2 or 3 zones, then a single stage heat pump is not going to work well so cross that off your list.

"I don't understand the logic about having a smaller return in the master
bedroom/den area. The return has to be sized for the amount of air the
zone will use. If it is too small then it will be have more noise."

just fyi...

often r/a is added in areas where doors will be closed. master suites

with several supplies..2 in bedroom one in bath, one in each walk in closet

requires a pathway when doors are closed for air to return to the system.

there are several ways to create this pathway. don't shut doors, transfer grills,

jump ducts or separate return air.

you can have too little return, but not too much.

people may say they leave bedroom door to master suite open all the time,

but you wouldn't hear complaints of ghosting if it were true.

best of luck

Thank you all for the comments. I won't take more of your time at this stage unless you wish to add more.

Return air Based on comments, I think the original dealer I spoke with had prelim design with far too little ra, as they were planning on just two large ra (one downstairs and one up). A different prelim design had suggested (appropriately sized) but smaller ra for Master BR and Guest BR/den especially if the last two were to be a separate zone.

Ghosting I read a bit on houzz and http://www.homeenergy.org/show/article/id/1360 Master bedroom with pocket door would be closed and even though undercut is planned seems like potential biggest possibility of negative air pressure unless properly planned. It is 250SF/9' ceiling, would one ra placed high up on lighting soffit surface be adequate, or would it be more likely two would be needed?

@fsq4cw Won't consider radiant floor heat; cost as well as too unresponsive for my situation.

One return properly sized and located for upstairs zone should be fine...but unless you plan on having individual room returns which are the best, you would want a minimum of 3 central returns for main floor again properly sized and strategically located for best airflow and comfort for such a large area. Anything less will be problematic.

And back to Mike's post. You will see little to nothing on operational savings for zoning controls. That I agree. However, there may be some upfront savings with zoning control due to only one system for the home. Of course you lose a measure of redundancy.

IMO

If you are going to zone, then I would think that 2-stage or variable compressor would be pretty much required. And with these a variable speed blower.

You might look at two smaller systems rather than zoning a large system and see how that prices out.

Air returns Again, much thanks for input/education. If there are sufficient number of air returns, and with variable speed blower on air handler, am I safe in assuming that each AR would be quiet enough that even if you were say 5' away from it that you would hardly hear that it is on? I ask this because with a modern home and open floor plan there aren't that many wall options for air returns, and some of those are reserved for art work.

Am I correct that air returns can branch off of each other versus each being its own duct work run back to air handler?

Would an air return as part of a large K island (more than at toe kick) make sense as an option? Would it be quiet? Not create a sense of draft if sitting on stool near it? Added later ... A friend indicated that they'd had poor exp. with air return near K, and it distributing cooking aroma to distant parts of the house.

@weedmeister thanks for input on zoning and alternative approach.

@tigerdunes thanks Above you suggest Trane XV18 TAM8 air; I like alot about XV18; however ...

In other threads, you've cautioned against XV18 as newer mdl little hist; & also: "I
prefer Trane heat pumps over Carrier primarily due to electronic demand
defrost, a feature Carrier/Bryant does not have."
"If you
plan on zoning areas of your home off one system, I still believe Carrier/Bryant
offers the best integrated zoning system and components under one umbrella."

I'm a bit confused. 3 zones 830SF upstairs; main floor 1430/900 air handler will certainly be variable speed, but what about HP? It seems like a VS HP is what you suggest, and definitely like the quiet db ratings, but should I look at comparable Carrier/Bryant vs HP which I believe have better efficiency specs?

High desert Oregon heating degree days 6926 cooling 151 base 65. Very large 35 degree dinaural temp change during summer
so will have opportunity to really cool things down overnight. Very
little humidity.

For your situation and if you plan on zoning and using one system, I do recommend the var speed condensers whether Trane/Am Std or Carrier/Bryant. All of these brands with the var speed condensers are new on the market and relatively little field history. The exception would be the Greenspeed and Extreme HP models. Those come with an inflated price. It would seem that your zoning situation would be relatively simple and Trane /AmStd would be fine. However with new construction and multiple zones, Carrier/Bryant offers the best total integrated model in the marketplace under one brand umbrella. Most Trane/AmStd dealers Idealers I rely on Honeywell zoning controls which Trane/AmStd have had a longtime partnership. As far as electronic demand defrost which I prefer, Carrier/Bryant HPs do not offer this great feature. Since you live in an area with a moderate winter heating climate, EDD becomes less of a factor. With everything, there are always trade offs.

IMO

@tigerdunes thank you so very much I wish you were here, or local dealers had 1/10th of your smarts and clarity. And thx for elaborating on what you mean by Carrier zoning being under one umbrella, and Trane doing its zoning typically via Honeywell zoning. You really have saved me a lot of time.

With zoning, 2-stage condensor can work ok.

Since this is new construction, there is the Manual J (estimates equipment size) and the other one whose name I can't remember that determines the duct work.

Don't put a return in/near the kitchen. You won't want it there any more than you would want it in the bathroom. ;-)