New Guest
What should I look for in comparing two new builder homes energy effeciency?
Home 1: 2 story, 3400sqft, 2 outside ac units (16 SEER)
Home 2: 1.5 story, 3000sqft, 1 outisde ac unit (15 SEER)
Is having 2 ac units going to give me greater energy effeciency?
I am comparing two builders in Allen, Texas: Ashton Woods
and Drees
Professional Member
It's going to cost you more in the long run for 2 ac's. Maintenance, repairs, and replacement. BUT, a big 2 story house in Texas would need 2 ac's, one for the first floor and one for the second floor - it's all about Comfort.
Second home - 1 ac should do just fine for 1.5 story house. Less expense for maintenance, repairs and replacement. Electric bill should be a little less too.
Banned
With either home or system, adequate return air will be essential.
Do not, and I repeat, do not allow them to just use a wall cavity for the upstairs return. Needs to be a properly sized sheet metal duct. Ask them for equipment and duct plans for both homes and post your findings here.
Professional Member*
These are tract builders. You and I both know they don't use sheet metal for anything other than possibly a secondary drain pan. I'm not even sure that they would offer it as an option if you bought the house before it was built. I'm surprised they are even offering as high seer rating on the equipment as they are. Probably a 14 seer with an aftermarket coil. To the OP, 2 systems are going to cost more when they break and you'll have to replace them at sometime. On the 1.5 story, as long as you have zoning you'll be ok. Otherwise you'll get the hot upstairs syndrome.Originally Posted by seatonheating
I like DIY'ers. They pay better to fix.
God Speed, Jim. We'll miss you - 2-26-23
You'll want 2 systems.
New Guest
The builder doesn't give out this kind of information until we sign papers and give 5k earnest money. According to the saleperson, even after this, blueprints are not handed out, but we might be able to get them.
Basically, we are signing up to build a house on "marketing papers". In other words, we see the dimensions of the house and a picture of the Elevation, but that's it. Unless the 45 pages of paperwork is more revealing (which the salesperson said it isn't), then our only choice is not to build at all or just put down the 5k and hope for the best. Well, we have seen a similar home that's complete and it looks nice.
We are allowed to go to look at the design center, but no pricing is given. We have never built a new house, the whole experience is quite overwhelming and odd...
The salesmen said there are 2 ac's and water heaters on the 1.5 story, with the top story having a return with some kind of tubing (not steel). The 1.5 story (correction 2700sqft) is the only one we are still considering. When adding the second story, I don't see an extra WH on the floor plan. It also doesn't specify # of ac's. This is a little concerning. http://www.ashtonwoodshomes.com/texa...#floorplan_tab (Auburn plan)
Regular Guest
As a rule of thumb, from an operating and comfort standpoint, it is always better to have more smaller systems. Initial installation will be more expensive, however you get the reliability of two systems (what are the chances of both malfunctioning?) and better controllability (two thermostats). You always want at least some kind of zoning on house with more than one story, however, two systems would be preferred.
Professional Member*
My vote would be for one system per story for North Texas.
Tract home builder offering higher SEER I can understand, but will they also offer a high quality installation to ensure buyer gets near rated SEER performance? Same goes for building envelope. High SEER on leaky house = crap for comfort and energy costs.
Psychrometrics: the very foundation of HVAC. A comfort troubleshooter's best friend.
Professional Member
Putting the AC units themselves aside, is there any difference in the type of construction. Does one have double pain windows and the other not. What kind of insulation? How about shading or passive solar gain from windows? There is a lot that makes more of a difference than just the size and number of units.
Professional Member*
Two A/C systems would be the best option. One system w/zoning wouldn't save you a dime on utilities because it would probably run longer & you'd probably always complain about how one floor isn't as comfy as the other. Especially if it's installed in a tract home. The installing contractor'll find some way to screw it up. Trust me.
WHY?
Regular Guest
If I was in your position, I'd walk away and find an independment builder with a good reputation who would work with me to build what I want.
Professional Member*
10-4!
I wish I had a $1.00 for every response I deleted.....
"Decidedly Superior in a twisted pathetic way".....
Regular Member
When they see you putting your checkbook back in your pocket and walking out the door, they'll soon be more cooperative. Money talks and b_llsh_t walks!
Professional Member*
More zones usually equates to more comfort and lower energy cost.
If you not in that part of the home, you can set the temperature up or back depending on what your needs are.
Professional Member*
If a builder told me that I'd have to give him a 5k deposit before he'd show me the detailed plans....well there are other builders out there!! Also agree to most posters, either two systems (one each floor) or a zoned system installed by an experienced HVAC contractor who has zoning experience.
Professional Member*
Orientation and shading, and if bedrooms face E, W, N, S, will have dramatic effect upon comfort and control as load shifts throughout the day. You'll often find big variation up and down, side to side. Generally 4 zones allow for nice control of this.
Getting zoning done right would be ideal, but might be challenging. If you do go down that path be very careful, oversizing w zoning can be disastrous, but if you get it right it'll be the nicest solution.
God Speed, Jim. We'll miss you - 2-26-23
No different then charging X $ for the results of a load calc, instead of letting the customer use them for free to get other estimates.
Professional Member*
The builder owns the plans as well. Plans aren't free and usually cost several grand to have drawn up. That sort of stuff is proprietary information, buying the house does not entitle you to the plans. You could take them and re-sell them saving some other builder lots of $$$. You might be able to get the plans by signing a contract saying you won't release them and paying for them. Kinda like proofs from a photographer, you can't get copies until you pay for the copyright to them.
I like DIY'ers. They pay better to fix.
Professional Member*
Guess it's not clear what "show me" means. Let you see them or let you HAVE them.
Professional Member*
We don't do tract homes because they (this type of builder) generally use the cheapest equipment, installed by the lowest priced contractor. (Results in granite countertops and oak floors and trim in a house that has very poor comfort.) We simply don't want to be in that group. We'll come out in a few short years and put in a really good system. But once the home is finished, it will be REALLY difficult, if not impossible to improve the air flow to the 2nd floor. That's the reason so many 1 1/2 to 2 story homes will not cool in the upper floor, and the HO has to go buy a window unit in summer in order to live up there. Sad, but true too many times!! We have gone back after a house was "done" and installed a zone system for the HO, but the builder had to have his HVAC guy install the ductwork in a certain way so the upper floor supply duct was it's own seperate riser duct and could be seperated from the lower main floor. And of course this connection had to be within an unfinished area of the home. Can be done, just needs to be planned that way. Good luck, as you're asking the right questions!!
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