I'm building, what are now my best heating and cooling options?

Champ6

I've loved my 1925 bungalow with 1 pipe steam heat. And this venue has helped me make it as efficient and comfortable as I can imagine. Especially comfort. I also love steam locomotives, so steam is my joy (almost as much as my partner and my Studebakers) Life changes, and now I am starting to plan to build our dream/age-in-place home.

So what about HVAC? I'm in the mountains of western NC, and sadly, winters aren't what they used to be though nothing like the NE, upper MW, and other locales. Still, I'll miss my boiler and BF cast iron radiators. I LOVE steam.

The new home will be one story over basement. I don't know that any new modern steam systems exist, especially with BF cast iron radiators.

What are my goals? Energy efficiency yet reasonably minimal complexity. Warm feet in the not so cold winters. Air conditioning is still a must. Things change, but heat pumps still suggest cool, drafty ducts.

What would this august body suggest? TIA!

delcrossv

Sounds like a job for a mini tube system

https://forum.heatinghelp.com/discussion/comment/1223813#Comment_1223813?utm_source=community-search&utm_medium=organic-search&utm_term=%22mini+tube%22

Larry Weingarten

Hi, I'll take a stab at it. The best heating/cooling system is none at all... or as close as you can get to it. This suggests that building a very efficient structure is the first step. It's possible to build in a way that uses only 10% of the energy per square foot of living space that a normal home uses. I've done this and at a lower cost than conventional construction, by getting my hands involved in the building.

So, I'd start with a super efficient shell. I just read an article "Prepare for a Gray Swan Climate". It discusses weather extremes we've never seen before, and how the science makes it clear that's what our future holds. This is another reason to build a very efficient home as it will stand up to severe climate better than conventional construction. A good shell can even allow you to be off grid should the need arise. And then, energy prices don't really go down. I like to think about energy costs as they relate to the life of the building. I'd build something that will still be considered efficient 25 or 50 years from now. That way, the house doesn't become obsolete any time soon.

Once you have this great house shell, heating and cooling become easy. The systems get smaller and simpler. Money saved there helps pay for the better shell. Anyway, that's my 30,000 foot view of it. Others will have useful information

Yours, Larry

ethicalpaul

Since you're asking:

2x8 exterior framing with foam insulation. Tightly sealed to the point where it will require an exchanger.

A steam boiler with modern steam radiators since you like steam

A mini split system or one of those small tube systems for cooling, whatever those are called.

Hot_water_fan

I think the question to answer is how much do you want to spend! With AC, a heat pump and/or furnace is the cheapest option. It’s also comfortable if done right, but or course everyone has different options about what is or isn’t the most comfortable. Nothing (well besides $) is preventing you from installing steam, heat pump and furnace . 

If energy efficiency is the goal, truly, then a heat pump wins in that climate. 

If you’re feeling ambitious, an air to water heat pump gets you efficiency, warm floors and cooling all in one. 

jesmed1

Here's some inspiration for your new high-efficiency house:

https://elemental.green/the-love-shack-a-net-zero-energy-home-in-north-carolina/

Daveinscranton

I lived in that area for a bit.  Beautiful part of the country.  It still got plenty cold.  And pretty warm in the summer.

 I would suggest ICF (integrated concrete form) construction for both basement and house.  I would do an ICF floor too but that is me and I like radiant floors.  

My stonemason friend says that an ICF roof is possible too.

Incredible comfort.  Cheap to heat and cool.  House will be standing in 100 years and maybe 1000.  Bug resistant.  Rodent resistant.  Wild fire resistant too.  Your insurance company will love you.

The You Tube clip referenced above on steam was fascinating.  My second choice would have been steam but the radiant floor was cheap and easy.  If the pex goes in my lifetime (it shouldn’t), I would probably do steam.  

If you use ICF, plan ahead.  You need chases and escapes for your mechanicals.  Core drilling later is no fun at all.

 I love ICF.  Build like Lego’s.  Follow the instructions.  Easy to do a stone exterior and just Sheetrock the interior and done.  My stonemason friend can now do a stamped concrete floor that is hard to distinguish from stone.  Had he been able to do that years ago, I might have done it.

Energy prices are not going to go down.

You can have (small) steam heat if you like.  

You can do a bit of passive solar with south facing windows.  Deciduous trees 🌳 can be your sun shade.  

Fun project!  Enjoy it.

clammy

Aside from insulation and weather sealing I would look to set my home where my winter solar gain is high and summer solar gain is low . I would also look into longer roof eaves and gables leaves more shade and less solar gain depend on how the home is sits . As some suggest to make it air tight I would suggest if doing so look into some type of fresh air makeup Hrv or Erv . As in most new construction sealing of all pipe and electrical penatraction should not be over looked . Unknown to myself as to what your local building codes are high on my list for any climate is attic insulation the more the better . If installing central ac I would suggest installing in basement keeping everything with in the envelope of the building . I know in that area heat pumps are the most common systems and if installing a hot water system remember you may have a difficult time locating those w experience so keep that in mind . As for duct work have it sized properly and external wrapped and all duct joints mastic sealed as w all connections , request a heap filter system to keep your fan and coil and supply ducts as clean as day one ,this happens when all return ducts are also sealed . My thoughts are that w a properly sized heating and cooling system installed properly and a tight home your operating cost should a mim . As other s may have stated or not the building envelope Is the most important thing then heat lose and heat gain for proper sizing .
All who have lived w steam are usually unimpressed w any other type of heating system especially hot air but if done correctly ( costly ) hot air can be done and operate quitley but there’s will be space taken away for proper duct work . This is the number one reason most duct systems stink is because the saving of space and running of flex instead of hard duct . That being said stay away from Florida distribution type systems ,I see guys doing them and it’s crushes me to see such hacking and garbage tin work but it,s seen in every field .
Peace and good luck clammy

yellowdog

if i was to do it again, i would do it the same as i did 18 years ago. radiant heat in the basement slab and the main floor (and the entry and the garage) powered by a gas modcon boiler with a couple heat pumps for ac during the summer and shoulder month heating. only thing i may change would be a heat pump water heater in the basement for a little dehumidification during the summer versus the indirect i have now. wife grew up in a woodstove house and her only complaint was there is no hot spot in the house. a freestanding gas stove took care of that and gives me some backup heat if i need it when the power goes out.

WMno57

Don't forget to keep the Studebakers warm too. I'm a car collector also. Maybe someday I'll build my dream ageing in place home.

• Small 3 bed two bath ranch (about 1200 sq feet)
  
• Wheelchair accessible (can't predict if I'll need it, but I'm tired of moving)
  
• Full basement, insulated floor, walls, footers
  
• English depth basement with windows
  
• Radiant basement floor
  
• Attached garage/shop with two post lift, 4 car, 2 wide 2 deep
  
• Radiant shop floor
  
• Large detached pole barn (un-insulated and un-heated)
  
• Clutter and junk resides in pole barn, keep that shop neat and clean
  
• Hot water heat with vintage CI radiators
  
• Central AC for house
  
• Window shaker AC or cheap mini split for shop
  

Cost per sq ft would be high, but If I kept the house-shop small enough that would keep total cost down.

WMno57

ethicalpaul said:

2x8 exterior framing with foam insulation. Tightly sealed to the point where it will require an exchanger.

Do this instead of 2x8s
https://www.finehomebuilding.com/project-guides/framing/lstibureks-ideal-double-stud-wall

delcrossv

Wow! With all that framing , ICF looks pretty attractive. It also has the advantage of no organics for bugs to eat/ nest in etc.

We're doing a 600 student school in the upper Midwest and the labor cost savings of ICF vs CME's (cinder block) was a real win for the school board. As said above, it's an at least 100 year building and the insurance underwriters love ICF.

hot_rod

For heat, a panel radiator system running 120F. Comfort from the radiators will be similar to cast iron steam and allow for more heater options. Maybe an air to water heat pump fits nicely in that climate for heat, cooling, and DHW. A small combi boiler for a hybrid system.

I used ICF on a few additions at my place in Missouri, a similar climate, be sure to use a borate treatment, ants love to burrow into IFCs

Theo_G

I will put in a second vote for steam mini tube, but I will add that you should add a vacuum pump and make it run sub-atmospheric to get steam under 212F. It's an inexpensive system to install compared to traditional steam, and you can use an inexpensive diaphragm vacuum pump with a drain separator before it to keep steam from getting in and damaging it. There's no reason this system couldn't be run in vacuum like any other 2 pipe system. Although a standard mini tube system is plenty efficient, why not improve on that further by making a vacuum mini tube system? This system is run in 3/8 soft copper tube, with small diameter copper or iron mains, but otherwise functions like any traditional 2 pipe system with traps. For A/C use mini splits and keep the heat pumps doing what they do well, cooling, use the mini tube steam for heat. I don't think that any other system will compare to the steam that you love to be honest, except maybe hot water with CI rads. New CI rads are still being manufactured today as well. I do agree that mini tube is probably the best choice for you, whether you add a vacuum pump or not. Someone may be able to recommend a combination vacuum pump/condensate pump although I am not sure a small enough size exists.

bburd

While I'm enjoying these suggestions of exotic systems, a homeowner should keep in in mind that most HVAC contractors are incapable of repairing and maintaining ordinary existing steam systems, even in parts of the country where these are common.

Who will work on that wonderful mini tube system in the future? What will a home inspector make of it when the house is eventually sold? Will prospective buyers demand money to rip it out and install something that local contractors are familiar with, like forced air?

going_commando

I'm not an HVAC pro (other than having an epa card and working on a few oil boilers) I'm an electrician by trade, but I would keep it simple. Dual fuel heat pump is the simple option. If the registers aren't blowing air at you, then you won't know that the air is below your skin temp so it won't feel cold, but the gas furnace is there when there is a cold snap and you want that extra boost without running electric heat strips. The fancy wall assemblies that people have posted are really cool and interesting from a scientific point of view, but I'm not convinced the payback in energy savings will offset the dramatic  increase in construction costs even if you could find anyone to build it.

I spent last weekend in an Airbnb in Burlington, VT and it had forced hot air and it was comfy as could be at single digits because the registers didn't blow air on me, so I just felt warm air. I am definitely a fan of steam and forced hot water, but most of the country is heated with forced hot air and it does work. If you have you equipment and ducts in conditioned space (to minimize that stuff fighting dramatically higher or lower temps than the space it's trying to condition) and don't have air blowing on you when the fan runs, your home will still feel comfortable. 

Take this all with a grain of salt, as I'm no expert. I am a nerd who researches the pants off of everything and try to pay attention to how comfortable I feel in different spaces with different types of heating/cooling systems. If I could have fit duct work in my low ceiling height basement I would install a ducted heat pump and use my forced hot water for when it gets really cold, but alas, it won't fit without far more work than I'm interested in engaging in. The technology has come far, but burning dinosaurs when it gets cold still works great, so having that as a backup should keep you comfy at reasonable prices.

EdTheHeaterMan

I moved from the Northeast to South Carolina's Low Country. My one story Slab or grade 1970s era rancher is heated and cooled by a heat pump located in the attic. Since the heat is unbearable in the attic in August, I'm sure that I have a much higher electric bill than needed with the standard R8 flex duct as the main distrubutio system. That said, we just went thru 3 days in a row of temperatures in the 20s overnight and with my old poor blood circulating legs, I can't seem to get warm at all. I wish there was an easy way to put radiant floor tubing in this darn slab...

Just my 2 cents worth.

delcrossv

bburd said:

While I'm enjoying these suggestions of exotic systems, a homeowner should keep in in mind that most HVAC contractors are incapable of repairing and maintaining ordinary existing steam systems, even in parts of the country where these are common.

Who will work on that wonderful mini tube system in the future? What will a home inspector make of it when the house is eventually sold? Will prospective buyers demand money to rip it out and install something that local contractors are familiar with, like forced air?

It's really just a two pipe system. Aside from being plumbed in copper and having a condensate pump (which one can dispense with if there enough height) it doesn't seem too exotic to me. (???) Not like it needs fabricated parts or anything. Mr Gill has installed a few of these, so evidently some customers didn't consider it too risky. IMHO.

WMno57

Hot_water_fan said:

I think the question to answer is how much do you want to spend! With AC, a heat pump and/or furnace is the cheapest option. It’s also comfortable if done right,

Forced air can provide a reasonably comfortable home in North Carolina, if there is a full basement under the house.
Radiant is much better than forced air for an auto repair shop though. Pulling flammable vapors and dust into a furnace/heat pump is not good. Laying under a car on a cold concrete slab is miserable. Same for standing on a cold concrete slab. If you have a high ceilings and a lift, the heat needs to be where the mechanic is, not 12 feet in the air.
If you have a boiler for the shop, why not heat the house with the same boiler? One AC can't cool both the house and shop (dust, fumes, etc) hence my suggestion for window shaker for shop.
My double stud wall suggestion was for Paul. If someone is considering 2x8s, double stud is worth a look.
For NC I would go single stud 2x4 or 2x6, with an inch or two of foam boards on the exterior, then a well sealed house wrap.

WMno57

More on single vs double stud walls.
The goal is to avoid thermal bridging. A 2x8 is a thermal bridge if there are no foam boards on the exterior side. Double stud walls are great for extreme cold climates. For North Carolina, one inch of foam boards on the outside of a single stud wall is a good enough way to reduce thermal bridging.

hot_rod

The staggered stud sure is easy for plumbing and wiring on the exterior walls. 2x6 plate with 2x4 studs staggered.
Use engineered studs like TimberStrand or rated finger jointed studs in kitchen walls for a perfectly flat wall for cabinets and counter tops to mount against.

leonz

Champ6 said:

I've loved my 1925 bungalow with 1 pipe steam heat. And this venue has helped me make it as efficient and comfortable as I can imagine. Especially comfort. I also love steam locomotives, so steam is my joy (almost as much as my partner and my Studebakers) Life changes, and now I am starting to plan to build our dream/age-in-place home.

So what about HVAC? I'm in the mountains of western NC, and sadly, winters aren't what they used to be though nothing like the NE, upper MW, and other locales. Still, I'll miss my boiler and BF cast iron radiators. I LOVE steam.

The new home will be one story over basement. I don't know that any new modern steam systems exist, especially with BF cast iron radiators.

What are my goals? Energy efficiency yet reasonably minimal complexity. Warm feet in the not so cold winters. Air conditioning is still a must. Things change, but heat pumps still suggest cool, drafty ducts.

What would this august body suggest? TIA!

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One pipe overhead steam would allow you to have one riser and one floor hole from the boiler in the end of the basement to the attic that would feed the radiators from the insulated attic space where the header pipe would be buried in insulation.

The pipe would be located either in the center using cross pipe adaptors or to one side using down facing tees to feed the right side to unions and elbows for the drop pipes for each radiator and an elbow and drop pipe for the dry steam to each radiator on the opposite side and any middle rooms.

I would not use foam insulation due to the off gassing issues that they have found.

ChicagoCooperator

If you build a super insulated house the comfort - in the sense of having cold cold spots, drafts, etc - really improves on it's own and you don't need much in the way of supplemental heating. You're better off doing an air based system with an exhaust air heat exchanger since you'll need ventilation and dehumidification.