Sure, this is non-exhaustive of course, but here's a few of the items on the list I personally think are very important.
* Foundation footings set to bedrock and insulated above the freeze line
* Exterior walls framed in 2x6 or 2x8 studs w/ a preference for non-bridging stud products like t-studs
* Exterior continuous insulation
* Kitchen range hood needs to be externally ventilated with proper make-up air system
* Using an ERV (Energy Recovery Ventilator) with filtered intakes for doing fresh air distribution within the home
* No use of plastic flooring products (e.g. linoleum, vinyl, carpet, LVP, LVT, et al) which off-gas and spread plasticizers within the indoor envelope
* Consider use of alternative methods of framing vs stick framing, like using ICF (Insulated Concrete Forms)
* Natural gas on-demand hot water heaters w/ electric instant hot systems close to tap for showers
* Roof trusses and decking properly constructed to account for the weight of solar panels on the south-facing slope
* Split electrical paneling for high voltage (230V+) and low voltage (120V) circuits
* Post-meter paneling for breaking out to circuit panels w/ a space for setting up a transfer switch to support future grid-tied solar with battery backup
* All electric appliances w/ the exception of on-demand water heater and sealed gas fireplace, this provides a pathway for higher energy efficiency / lower carbon emissions by using solar
* All cabinet work should be hung using french cleats for durability
* Exterior door frames should be installed fully to the studs (e.g. use 3-4" long screws)
* Interior doors should be solid core
* All interior walls should contain sound-rated insulation to reduce noise pollution and improve climate zoning
* All interior walls should be boarded with sound-sealant and noise rated drywall-type products
* Subfloors should be insulated and there should be sound/thermal insulation underlayment below the flooring
* The final construction prior to drywall should be able to achieve a blower door test score of ACH50 1.5 or lower with the make-up air and flue vents closed.
Not all of these things would be required by code currently in Europe, but they're all good ideas for durability, efficiency, or safety. This is obviously with the intent to use rooftop solar power as well. If I do build a custom house, it'll be built to the Passivhaus standard.
Your list is a 100% match with my requirements list for my build in the Chicago area in 2018. Sounds like you may have also spent a lot of time on Green Building Advisor articles and forums.
Our biggest challenge was finding contractors willing to execute to plan. My wife and I ended up doing a lot of work ourselves especially around insulation details and HVAC systems.
Yes, I am a big fan of Green Building Advisor and I also watch a lot of building YouTubers, predominantly Matt Risinger's Build Show[1].
He has featured other builders and home owners who also have websites or channels, and there I've found more information. There was one chap in central Canada that built a ~5k sqft house that only needed around 1600W to heat in the winter in subzero temperatures. That's the type of energy efficiency we need in new home construction if we're ever going to make a dent in climate change.
> Foundation footings set to bedrock and insulated above the freeze line
Not knocking it, but is this normal for single family home construction? Is it possible with reasonable cost? Is it primarily for an earthquake-prone region? The idea is cool, but I thought only skyscrapers went down to bedrock.
The answers to your questions definitely vary by region. If you're building a house, one of the first things you should do is get a structural engineer's assessment of the lot before you plan the foundation, because soil type, bedrock depth, freeze lines, environmental concerns, etc. all affect this.
But yes, it's fairly common to do this if you care about structural integrity over the long term. In areas with soil type that support it, it's more common to do simple slab foundations without footings, but in most of the US footings are used and the foundation is built as part of a crawl space or basement. Sometimes excavation for a basement is deep enough to get below frost line, or to bedrock itself, it depends greatly on the region.
"Reasonable cost" is kind of a subjective thing, but I'd say starting with a a good foundation is a bare minimum of requirements for what would end up qualifying as "constructed properly", so at least as far as I'm concerned this is an absolute requirement.
I'm still confused. Basements go below frost line, sure, but bedrock can be hundreds of feet below the surface. I don't know of any home I've ever seen that has piles driven down to bedrock. Is this just a regional thing? What am I missing here?
Yes, bedrock can be many hundreds of feet below the surface, and in other areas bedrock can be pretty near to the surface. This is one reason why you should have a geologic and structural engineering report done on a plot before you build (and arguably before you buy the plot). Depth to bedrock greatly factors into the cost if you intend to have piles put in to support your foundation.
In some areas, it's not actually necessary to drive piles to bedrock to get similar stability, instead piles are driven to refusal at a calculated depth based on the expected foundation load. In the regions I'm planning to build though, bedrock is nearer to the surface (or in some cases exposed above the surface as an outcropping), which means that the proper way to do things is to drive piles to bedrock.
I am not a structural engineer, and I don't know what is necessary where you live, my list was made for my specific purposes and shared because it was asked, it's not an argument in favor of any specific structural techniques, you should speak to a structural engineer in your area.
This sounds like you have thought about it a lot. Assuming I live in a moderate climate, is there a version of your list for someone who prizes having the windows open as much as possible? Eg I'd like a house where the kitchen opens onto outdoor living space, and we keep those doors open almost all the time. In that context, I've always thought leaky old windows were a good thing, because they allow for fresh air. What am I missing? Are these sealed houses nice to live in or do they feel stale?
> Are these sealed houses nice to live in or do they feel stale?
These well sealed houses actually have /better/ indoor air quality than a typical house designed for cross-flow from open windows. The reason is that they use powered ventilation that essentially runs all the time, so you have constant fresh air entering the house and stale air leaving, and you have specifically designed and planned exhaust points. The bonus to it is that it's much more energy efficient because the ventilation can be done using energy recovery ventilators (ERVs) which equalize the temperature between indoor and outdoor air +/- 3F, greatly reducing the cost to maintain a set temperature indoors while getting fresh air from outside, and the air can be filtered through MERV16 / HEPA filtration, reducing dirt and allergen ingress.
If done properly, the absolute best indoor air quality is found in Passivhaus construction.
Yes. We are not quite net zero given snowy winters in NH, but overall feels good.
We are on air sourced heat pumps. I think the US is really behind in thinking about creative geothermal like borehole heat pumps which act as a thermal battery (pump heat into ground in summer, extract it in winter.) They work but I can't imagine they are the best solution in my climate zone.
Also, for energy usage is seems appliances could use innovation. Why am I not recapturing the heat from my clothes dryer? Why do I have a separate refrigerator (heats house) and water heater (cools house) inside my house?
We tried a heat pump water heater but it was a total fail, as it is equivalent to putting an air conditioner inside your house. We had it in the ground floor of our walkout, which even in summer never breaks 70 degrees. Kids were complaining and actually turning the heat on...
That's... not actually true at all. In fact, in large parts of the country it's /required by code/ to separate 240V and 120V circuits, such as in most of South Central Texas (pop ~5M or so). There are absolutely 120V panels, and they are commonplace.
I will agree, however, that in much of the Midwest and Northeast it's more common to see single-panel installations. Separating the panels is important for safety, though, and it also allows better circuit routing when running the electrical.
This is really interesting. It must be region-specific, because I'm in the northeast and have never seen or heard of this practice.
Residential power around here is delivered as 240V split phase. Meaning, the service entrance load center has a bus bar for each leg, and the neutral is 120V from either leg. So you can have 240V circuit breaker that spans both legs, or a 120V that uses one in combination with the neutral.
How does the arrangement you're describing work? I tried searching for 120V-only load centers, but wasn't really finding anything. Or, did you mean bridge together the two legs on a traditional load center and use it as a subpanel of the service entrance?
Yes, that's how it works. Residential panels technically aren't rated by voltage, they're rated by amperage and the number of breaker openings. What is generally done here in South Texas is that on the exterior next to the meter there is a small primary panel for all the 240V circuits, and off of that a 100A leg feeds a physically larger subpanel in the garage area that has both legs bridged, acting as a 100A subpanel for 120V circuits.
Personally, I think having the 240V circuit panel outside is dumb, and the amount of times I've seen my or other folks breakers fail due to weathering is pretty much the reason why. How I've seen this done on new builds where care was taken is that both panels are brought indoors and the only thing outside is a split out to a subpanel specifically for the A/C / heat pump unit. Everything else comes indoors, there is a smaller panel setup for 240V and a subpanel for 120V circuits.
Obviously as the power entering the home is 240V split phase, you must break out a subpanel for 120V only if that's your intention.
* Foundation footings set to bedrock and insulated above the freeze line
* Exterior walls framed in 2x6 or 2x8 studs w/ a preference for non-bridging stud products like t-studs
* Exterior continuous insulation
* Kitchen range hood needs to be externally ventilated with proper make-up air system
* Using an ERV (Energy Recovery Ventilator) with filtered intakes for doing fresh air distribution within the home
* No use of plastic flooring products (e.g. linoleum, vinyl, carpet, LVP, LVT, et al) which off-gas and spread plasticizers within the indoor envelope
* Consider use of alternative methods of framing vs stick framing, like using ICF (Insulated Concrete Forms)
* Natural gas on-demand hot water heaters w/ electric instant hot systems close to tap for showers
* Roof trusses and decking properly constructed to account for the weight of solar panels on the south-facing slope
* Split electrical paneling for high voltage (230V+) and low voltage (120V) circuits
* Post-meter paneling for breaking out to circuit panels w/ a space for setting up a transfer switch to support future grid-tied solar with battery backup
* All electric appliances w/ the exception of on-demand water heater and sealed gas fireplace, this provides a pathway for higher energy efficiency / lower carbon emissions by using solar
* All cabinet work should be hung using french cleats for durability
* Exterior door frames should be installed fully to the studs (e.g. use 3-4" long screws)
* Interior doors should be solid core
* All interior walls should contain sound-rated insulation to reduce noise pollution and improve climate zoning
* All interior walls should be boarded with sound-sealant and noise rated drywall-type products
* Subfloors should be insulated and there should be sound/thermal insulation underlayment below the flooring
* The final construction prior to drywall should be able to achieve a blower door test score of ACH50 1.5 or lower with the make-up air and flue vents closed.
Not all of these things would be required by code currently in Europe, but they're all good ideas for durability, efficiency, or safety. This is obviously with the intent to use rooftop solar power as well. If I do build a custom house, it'll be built to the Passivhaus standard.