Single vs Dual HVAC systems

[ktcribbs]

We are purchasing a new home (yet to be built) in Denver and our builder sort-of waffled when we asked about a dual HVAC systems. Our house is advertised as very efficient and has LowE windows and an external vapor wrap. It is a 2 story house with a full basement with 2900 sq ft in the upper 2 story's and 1150 sq ft in the basement. From everything I have read, the way to go is a 2 zone system but my builder insists on the single and will not allow a dual system. My question is this: Is the dual HVAC a convenience or does a house that will probably have 4000 sq ft of finished space require it?

[Gunnery Sergeant Hartman]

Your 2nd floor will be uncomfortable without some type of zoning...
Tell your builder you will pay the difference. Certainly this is what he is worreid about.

[framehvac]

I like zoning we do homes that big all the time.

BoltonNC is right Tell your builder you will pay the difference
Certainly this is what he is worreid about.

[uktra]

You need to check with http://www.buildingscience.com Research the Building America homes for your climate. Do not depend on your builder to do it. Insist on one unit with three zones minimum. You need a zone for each floor, and a return on each floor and any room that normally closes the door. Make him do a room by room load calc. and size the HVAC equipment properly. This is your house and your hard earned money. You are his customer. If you don't insist on doing it right, you will pay for it every month from now on!

[jared]

At least zone, you should probably have upstairs on a seperate system. One single stage unit proposed? You will never enjoy being upstairs....

[aircooled53]

I agree with the other's


Your house being built for your comfort not his. Ask for load information and ask a few other people that have had homes built in this area.

Mechanical Codes require load to be done.
Insulate with good windows high R-values.
Good Equipment-Installed Properly Saves (MONEY)

[Paul Pippin]

I agree with the others zoning is the best way to handle that problem. The very first problem is that a builder should not be deciding what you need to condition your house. Get a professional to do that for you. Unless he has a background in HVAC then he should leave that to the professionals. We don't try to build houses and he shouldn't design HVAC equipment.

[hvac-tech-lane]

Ask your builder if heat rises, or if he has ever seen a hot air balloon. I put 2 systems in my own house, upstairs comercial supply grills and return in the ceiling with a hydro heat and straight A/C in the attic, nice and simple and quiet. Same equiptment downstairs floor supplys with a low sidewall return, will be addig a heat pump this summer, system works wonderfully I can keep the upstairs perfectly cool on the hottest day with out freezing the first floor, and the first floor nice and warm on the coldest day without over heating the upper floor. trust me you need some kind of zone control.