A few questions about a new house build in KY
Hi, fairly new here, reading a lot, but trying to sign a contract in next two weeks to build ~ more or less, this house: http://houseplanit.com/plans/655653/655653-Traditional+1.5+story+home+with+4+bedrooms+and+3+bathrooms.htm
Briefly, it is a 1.5 story, about 1600 ft2 down (adding 2 ft to width for front entry garage and master closet mostly), 9 foot ceilings (not the mix shown on website) save the vault in the 15×18′ great room; 680 ft2 upstairs, 8 ft ceilings.
This will be in Lexington, KY (center of state, usda zone 6b.
The house will face nearly north (about 15 degrees towards east off of north) and have a lot of glass on the south/great room side) – But can’t afford solar right now.
Electricity … need to double check but believe it’s about $.065/kwh.
Our habits are to be, more or less, at 72F year round – sometimes I can get her to 68F on winter nights; little use of windows due to both of us having allergies. Please don’t suggest different settings, I understand those savings, it is what it is.
My wife needs everything on one level and we are empty nesters; I may have my office upstairs, but the goal is to be able to pretty much shut off the upstairs (3 bedrooms/bath; halls are open to great room below) unless we have guests.
I will install Aluminum radiant barrier in the rafters; I’d like to do the outer sheathing, but this may not work out (also I hear this kills cell phone reception, not an option as I work at home when not travelling).
EVERYTHING I see here in new builds uses Aluminum flexible ducts.
I am an engineer, have had a few houses built but it’s been over 20 years, so out of touch with current practices.
Currently two different builders spec 2 separate heat pumps, 13 seer (I’ll go higher, but moderate zone probably means not much considering payback); 3 ton down, 2 ton up.
My few primary questions, since I need to spec things very soon:
First – and this is my primary question: What would be the best hvac solution here? I sense the pro community in this area adopts new things slowly, but if I get a strong consensus on a superior solution, I’ll see which of these guys I’m bidding will let me work with a contractor that will do that; seems silly to miss the chance before walls are up.
– I’m trying to get them to one unit by adding mechanical chase; last house I built – 2 story of nearly same ft2 and features this worked well, I had dampers in the separate upstairs and downstairs returns and just switched the bias on them late fall / late spring and this really seemed to keep temps even top to bottom. Yes, I know most say airflow is most efficient, just saying this worked really well comfort-wise. Again, I hope to largely shut down the 2nd floor, BUT do want a reasonable recovery if I decide I need to use it – a couple hours, not half a day… unless it’s 95F + …
– I’m reading about minisplits… just too much to figure it out in short time frame. I think about at least using them for upstairs, but wonder if the evaps can be embedded in walls so they don’t stand out so far, would like to be able to turn them on from one location vs going to each room, etc. I’m not lazy, I will read and search here for answers, but often on forums like this searches yield wide and shallow results or too many conflicting results for a non-pro to sort out. But I will be trying to do that.
2. What are the 3 things I should do to ensure the house is tight? I’ll have Anderson 200 windows or equivalent; Higher cost windows don’t appear to pay back here with moderate climate and cost of electricity. Fairly moderate here, but it has been near 0F several nights this month (not normal) and 95F is very common in August, some years may have 5-10 100F days. I’m costing XPS sheathing, but it complicates construction, not a polyiso fan. I am very hands on; will be reading more about HERS recommendations/methods, etc, will check and remediate / caulk myself after contractors are done, etc. I read something about sealing different air spaces, will try to find that again…
Any help appreciated.
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