1)  What does it feel like to live in a "Passivhaus?"

It's really comfortable.  The indoor temperature is uniform from the floor to the ceilings and on every surface. There are no draughts.  The humidity level is constant.  The air is always fresh and free of dust, pollen, and airborne bacteria.  It's very quiet. 

2)  What is the goal of the Passivhaus Institut, International Passive House Alliance, North American Passive House Network and the New York Passive House Association?

Humans choose to produce over 80% of the energy they use from the combustion of fossil fuels combustion which produces carbon emissions.  Researchers estimate that carbon emissions prematurely kill two (2) million people each year and are responsible for global warming potentially leading to mass extinction.  Heating and cooling leaky buildings produces over 50% of all carbon emissions. Passenger vehicles account for another ~ 15%.  Seventy percent (70%) of all carbon emissions end up in cities. Sixty million people migrate to cities each year.  The Passivhaus Institut Building Standard for renovation (EnerPHit) and new construction reduces a building's heat and cooling energy demand by 80 to 90% when compared to current building code and it improves occupant comfort and indoor air quality significantly.  Manmade carbon emissions produce nothing beneficial.  Fixing this problem reduces the probability of mass extinction, increases life expectancy, enhances the quality of life and produces jobs and enhances economic growth. 

3)  How much carbon does my household produce right now?

An average household in Chicago living in a detached house can easily produce 150,000 pounds of carbon each year.  If you spend $400 to $500 per month between COMED, Peoples Gas and fuel for your car, you're probably producing at least 150,000 pounds of carbon per year of which 70,000 pounds could easily be attributed to just heating and cooling your house. The Passivhaus Institut Building Standard would reduce this by 80 - 90%.  

4)  How much energy will my family expect to use to live in 5485 South Ellis, "Ellis Passive House?"

  • Energy for heating and cooling approximates ~2000 kWh per year.  
  • Energy for hot water approximates ~1300 kWh per year.  
  • Energy for lighting, cooking, communications, entertainment, and all other uses approximates ~ 6400 kWh per year.  
  • Personal transportation in an EV (100% electric vehicle) at ten thousand miles per year would require an additional ~ 2500 kWh per year.

5)  How much will I expect to spend each year with COMED and Peoples Gas to live in Ellis Passivhaus without on-site solar?

  • Household:   9500 kWh per yr * $.15 per kWh = $1,425.00 per year.
  • Transportation:   2500 kWh per year * $.15 per kWh = $375.00 per year.
  • COMED would receive 100% of the energy expenditure.  Peoples Gas would receive 0% because Ellis Passivhaus uses zero (0) NatGas although service exists on the property.

6)  How much carbon will my family expect to produce living in Ellis Passivhaus without on-site solar?

  • About 9100 pounds per year versus ~ 150,000 pounds or more living in an existing or normal new construction house.  Ellis Passivhaus uses 100% electricity and 1 kWh of electricity from COMED produces .97 pounds of carbon. With on-site solar (or wind)  resources, zero carbon production can be achieved.

7)  Please explain the concept and effect of “on-site solar."

  • For Ellis Passivhaus "on-site" solar references an array of rooftop PV panels which will be "grid-tied" to COMED. 
  • A full array of grid-tied on-site solar (photovoltaic, PV) panels at Ellis Passivhaus reduces Total Expected Annual Energy Expense to ~ $0.00 but carbon production remains at ~ 9100 pounds per year.  
  • With grid-tied on-site solar, smart grid management, and lithium ion batteries, annual expected energy expense ~ $0.00 and carbon production approaches 0.00 (zero) pounds per year because on-site production is first matched with on-site consumption requirements.  This is our preferred solution.

8)  Can I charge my EV (electric vehicle) at Ellis Passivhaus?

Sure!  Ellis Passivhaus plans to install an on-site EV charging station.  However, without a PV array and on-site smart-grid management, the EV will produce 3x more carbon than a hybrid vehicle for instance. Stated alternatively, an EV that pulls its energy from the grid, produces the same amount of carbon as a regular vehicle that gets ~ 16 MPG making EV's among the worst carbon producers on the road per mile driven all else equal.

9)  What is "Passivhaus?"

It's a term of art coined by the founders of the Passivhaus Institut some 25 years ago.   It can be described as 1) the preeminent globally recognized building standard, 2) a building methodology, 3) an actual building, 4) a lifestyle movement, and 5) a moral and ethical choice.  Since its inception in 1990 the PASSIVHAUS INSTITUT and now i-PHA (International Passive House Association) has grown to be a global enterprise that drives building energy efficiency by engaging in ongoing research and the certification of people, products and buildings. Many major municipalities have adopted PASSIVHAUS INSTITUT principles into their local building codes including Frankfurt, Brussels, Dublin, and the Borough of Manhattan (NYC.)

Nearly 50% of global carbon emissions trace to leaky and poorly insulated buildings. Sixty (60) million people migrate to cities each year.  Seventy (70%) of carbon emission end up in cities. Carbon emissions cause the premature death of two (2) million people each year.    

A PASSIVHAUS INSTITUT Certified Building achieves an 80 - 90% reduction in heating and cooling energy demand to maintain the PASSIVHAUS INSTITUT required design temperature in comparison with existing buildings or new construction IRC standard.  Therefore, a PASSIVHAUS INSTITUT building produces an 80 - 90% reduction in carbon emissions all else equal. It also provides pristine indoor air quality and remarkable indoor comfort.

Plugging the leaks in leaky buildings could save the planet and would certainly improve the quality of life for all living things.

10)  What does "certification" mean?

The PASSIVHAUS INSTITUT certifies people, products and buildings.  They offer a Tradesperson credential and a Design/Consultant credential to construction and design professionals. Both require successfully passing a three hour proctored written exam. Product certification requires extensive testing by the PASSIVHAUS INSTITUT itself.  Certified products include windows, doors, ventilation systems, heat pumps, curtain walls, and flue systems among others. Certification for buildings requires the creation a Passivhaus Planning Package model, third party validation of construction details and the achievement of the required air-tightness standard through an independent test once construction is completed. Certification assures building performance.

11)  How does a "Passivhaus" work?

When it's cold outside we bundle up with fleece, gloves, hats, and down parkas made from intelligent and breathable fabrics.  Thus the energy from our bodies is retained and we stay warm while the vapor that's produced wicks away and evaporates.  The Passivhaus Institut Building Standard pushes this principle to its logical maximum.

12)  I've heard the mold growth frequently occurs in high performance homes.  What about mold growth and IAQ (indoor air quality) in Ellis Passivhaus?

Mold loves warmth and humidity and some mold types will even grow in your cold refrigerator given enough time.   That said, when interior humidity is held sufficiently low and interior temperature maintained at a comfortable level, the prospect for mold growth is all but eliminated.

Mold growth in so-called high performance buildings represents a design and construction defect reflecting the presence of too much interior water vapor which then condenses and induces mold growth generally on wood and drywall.   Many times this results from using spray foam or foam boards as the primary insulator, which is deemed "vapor closed," and not sufficiently offsetting this resulting condition with an appropriate moisture mitigation strategy.  Ellis Passivhaus  represents a PASSIVHAUS INSTITUT certification project which means that an independent third party Certified Design Consultant has modeled the project in “PHPP” (Passivhaus Institut Planning Package). As a design tool, the PHPP design process leads to an optimal insulation strategy that insures performance criteria requisite for certification. Air tightness and energy limits represent non-negotiable design constants in a PASSIVHAUS INSTITUT building.  In addition, the AEA, (Association for Energy Affordability) an independent energy consulting company, recently measured the air tightness of Ellis Passivhaus  at levels well below the required PASSIVHAUS INSTITUT global standard and some  nine (9) fold lower that the current IRC (Code.) To achieve actual certification Ellis Passivhaus must prove that it implemented both the insulation strategy and maintained the air tightness standard as it moves through the final phases of the project.

The PASSIVHAUS INSTITUT standard requires sufficient and continuous insulation and a very high level of air tightness, among many other elements.  A PASSIVHAUS INSTITUT certified building necessarily mitigates thermal bridges and other conditions that lead to temperature and humidity imbalances that enable mold growth. Because Chicago's temperature and humidity levels vary widely and not necessarily together, to mitigate the potential for mold growth to the fullest extent, 100% of the existing structure's vapor open walls were renovated and enhanced with vapor open materials which is to say that foam as the primary insulator was avoided on over 80% of the above grade wall exterior surfaces and in 100% of the interior wall and ceiling cavities.  Vapor can naturally migrate back and forth through these walls.  The roof and new construction wall assemblies (the addition) employ a hybrid insulating method consisting of exterior foam insulation and interior vapor open insulation which enable vapor to move from deep inside the walls to the inside space where it can effectively be removed. Since the air and water barrier applied to the exterior masonry is vapor open, to a lesser degree vapor can escape here too where it would potentially condense on the outside of the masonry substructure Lastly, to remove the prospect of mold growth to a scientific certainty, Ellis Passivhaus employs a whole-house mechanical dehumidification system to extract and maintain moisture at a desired comfort level that mitigates mold growth potential and maximizes healthfulness and comfort.

13)  Why should I want my family to live in a PASSIVHAUS INSTITUT Certified Building as opposed a so-called "passive house," a "high-performance house" a "newly renovated house," or a "new construction house."

Peace of mind. A clear performance expectation.  A PASSIVHAUS INSTITUT Certified Building undergoes extensive third party quality assurance and achieves certain absolute limitations with regard building heating and cooling energy demand and air tightness which far surpass current new construction standards (IECC 2015 = 5.0 ACH Pascal 50 vs PASSIVHAUS = .6 ACH Pascal 50.)  As a result, a PASSIVHAUS INSTITUT Certified Building is very inexpensive to operate because energy demand is reduced in the first instance by 80 - 90% given the required level of insulation as determined on a case by case basis and the uniform air-tightness standard. This standard also delivers remarkable indoor air quality and comfort because the PASSIVHAUS INSTITUT standard requires continuous and balanced mechanical ventilation and very low temperature variance across all surfaces.  The PASSIVHAUS INSTITUT standard is simple and clear.  It's based on the scientific method and has proven itself over a thirty year history through thousands of projects around the world.   If every building achieved PASSIVHAUS INSTITUT certification, manmade carbon emissions would return to levels not seen in 100 years.

As for non-certified so-called "passive houses" or buildings, or, so-called "high performance buildings," they could or could not be built to the exact same specification as a PASSIVHAUS INSTITUT certified building,  "Let the buyer beware." 

14)  How much energy expense should me and my family incur to live in Ellis Passivhaus, a PASSIVHAUS INSTITUT EnerPHit renovation in Chicago assuming $.15 per kWh? 

Using the PHPP for the building’s heating and cooling demand and Energy Star for appliances, the following applies for Ellis Passivhaus.  For some this will be aggressively low for others it will be more than ample.  This 7000 kWh and $1050 annual expense per year could be satisfied with ~ 15 PV panels.


HVAC:                                    ~ $450.00       PHPP, Energy Star

Hot Water:                              ~ $195.00        Energy Star

Kitchen and Laundry:             ~ $200             Energy Star

Internet, Lights, Laptops:       ~ $100             Energy Star

Other:                                      ~$100            Energy Star, other

15)  How much carbon per year will my family produce living in this PASSIVHAUS INSTITUT EnerPHit renovation?

Given the size, location and design of Ellis Passivhaus, family with an electric vehicle will consume about 9500 kWh of energy per year for all heating, cooling, domestic hot water, overhead lighting, communications, entertainment, and any other requirement. Since COMED provides electricity, at least 9200 pounds of carbon will be produced each year. With ~ 20 PVs and smart grid management carbon production would approach zero and so would monthly out of pocket expense.

16)  How many homes or buildings in Chicago could be renovated to the PASSIVHAUS INSTITUT EnerPHit standard?

Tens of thousands of opportunities present in Chicago alone.  Some say that NYC and Chicago combined result in > 1.5 million small building renovation opportunities present. 

17)  What is "Household Energy Demand?"

HED (household energy demand) or “site energy” represents 100% of the energy consumed at the site at the "household" level.  This would include all energy for heating, cooling, ventilation, domestic hot water, overhead lighting, entertainment, communications, EV's and all other uses.  In Chicago, it would amount to the quantity of energy reflected on one's People's Gas and COMED bills combined.

18)  What is "carbon?"  Why the big fuss?

The term "carbon" commonly refers to a variety of gases through the combustion of coal, natural gas, oil, wood, solid waste, and as a consequence of certain chemical reactions including the production of cement.  These gases create a thick blanket as they dissipate into the atmosphere and beyond.  Carbon constitutes over 80% of "greenhouse" gases which include methane, nitrous oxide, and fluoridated gases which collectively result from large scale industrial processes. Plants and trees absorb carbon gases in their life cycle process and release them when they die.  Matter itself takes the form of a solid, liquid or gas and accordingly its weight can be measured.  In theory, manmade greenhouse gases have overwhelmed our atmosphere leading to increasing temperatures on the earth's surface posing a mass extinction threat. On an everyday level, no one wants to breathe bus fumes.  Carbon emissions from combustion of coal and NatGas induces a variety of health issues. Some researchers believe that 2 million humans die prematurely each year as a consequence.

19)  What is the Total Household Energy Demand per year for an average four person family? Consumption differs at the household level with income and tastes but a fair range would be 70,000 kWh to 170,000 kWh per year or more.   Most of this relates to heating, cooling and hot water.  In Chicago, most families heat and make hot water with NatGas. It's easily possible for a Chicago household of four to use 100,000+ kWh of energy per year which generates about 120,000 pounds of carbon per year, very slightly below the national average.  This level can easily be exceeded. If a family's combined COMED and Peoples Gas bill averages $500 per month, that family is producing well over 120,000 pounds of carbon each year. Some 125 million single family homes exist in the US alone.

20)  How much carbon does COMED or Peoples Gas produce per unit of energy?

Energy from one unit of electricity produced by COMED produces about .97 units of carbon primarily because nuclear provides over 30% of their source energy.  One unit of energy produced from coal produces about 2 units of carbon. One unit of natural gas consumed produces about 1.25 units of carbon.  Nuclear energy produces zero carbon. Solar and wind energy produces zero carbon as well. COMED uses coal, natural gas and nuclear sources to produce some 99% of the energy (electricity) it delivers and ~ 7% is lost in transmission.  People Gas delivers natural gas to a site which is then ignited in the structure.  Ignition itself constitutes an efficiency loss of ~ 5%.

21)  Since Ellis Passivhaus represents PASSIVHAUS INSTITUT EnerPHit Renovation what is the building energy demand for just heating and cooling?  In “model space” it’s strictly limited to 7.92 kBTU PSF YR which in the case of Ellis Passivhaus translates into about 6200 kWh per year. The standard doesn’t prioritize energy sources in the first instance.  Prior to any undertaking, an extensive design process occurs where every square millimeter of the structure is modeled in an engineering design software called PHPP (Passivhaus Planning Packageto forecast energy demand for heating and cooling for the specific building.  For New Construction, the PASSIVHAUS INSTITUT standard limits annual heating and cooling energy for any structure to 4.75 kBTU PSF YR and for EnerPHit Renovation it’s 7.92 kBTU PSF YR.

22)  Does the PASSIVHAUS INSTITUT certification criteria address energy requirements for domestic hot water, lighting, and appliances? No. Not directly.  But, the PASSIVHAUS INSTITUT certification criteria alone makes the building "Nearly Net Zero" which means that it's far less challenging to satisfy the Total Energy Demand with on-site solar production in many cases.

23)  What's the difference between a "Net Zero Energy Building" and a "Nearly Zero Energy Building?"  A Net Zero Energy Building draws energy from the grid but supplies as much or more energy back to it from on-site energy production form sources like solar PV panels on balance.  Hence, a very inefficient building with larger on-site production could be a Net Zero Energy Building.  In this instance, carbon production remains relatively high even though the grid is being fed more electricity on balance.  A PASSIVHAUS INSTITUT certified building, over tens of thousands to projects and decades of data, can be shown to significantly reduce building energy demand for heating and cooling by > 80%.  Hence, demand for carbon based energy sources significantly decreases in the first instance. This leaves more carbon energy available for industrial production and transportation. We should really aspire to a standard that minimizes harmful energy sources like fossil fuels and nuclear for household consumption.   The PASSIVHAUS INSTITUT Building Standard enables this outcome when combined with a relatively small PV grid in many instances.

24)  How should I think about Energy Star, LEED and other green building standards compared to the PASSIVHAUS INSTITUT Building Standard, "Passivhaus?"   A certified PASSIVHAUS INSTITUT building has frequently been described as "Energy Star and LEED to the nth power."  If meaningfully reducing carbon emissions, increasing occupant comfort and maximizing indoor air quality are objectives, the Passivhaus Institut Building Standard for renovation and new construction presents the most rigorous and certain solution.  Other standards fail to achieve the performance benefits the PASSIVHAUS INSTITUT Building Standard routinely achieves in terms of comfort (indoor air quality, quiet, weather event safety) and energy efficiency.

25)  Given the expected Total Household Energy expense for this project, how much carbon will be produced by an average four person household living in this house?  On a net basis, about 5 pounds per day with PVs, 26 pounds per day without PVs versus 178 pounds per day for an average family. That's about 1825, 9490 and 65,000+ pounds per year respectively for a family of four in Chicago. We should really aspire to produce 100% of the energy consumed on-site.  With affordable smart grid management and on-site batteries, independence from grid sourced energy is all but assured even in the most energy demanding climates like Chicago. 

26)  What creature comforts would my household give up relative to an average household?  None.  In fact, occupant comfort will significantly increase.  You can have all the digital toys you want.

 27)  What is the price of natural gas in Chicago?  About $.75 - $.85 per Therm, but it can vary.  It's among the lowest in the nation.  Over the long term energy prices rise 3% per year on average.

28)  What's a Therm?  100,000 BTUs.

29)  How many kWhs are there in one Therm?  29.3

30)  How many watts are there in one BTU?  ~ 3.41

31)  What is the price of electricity in Chicago?  About $.16 per kWh, about average nationally.  Over 70% of COMED's source energy is carbon based and at least 7% is lost in transmission.

32)  How does the price of energy in Chicago compare with other metropolitan areas? Natural gas is quite inexpensive and electricity is about average with most major metro areas.  In SF Bay Area it's about $1.70 per Therm and about $.20 per kWh.  In NYC, $.95 per Therm and $.19 per kWh.

33)  What is the blended USD price for energy in Chicago at the consumer level?

Just $.05 to $.06 per kWh!  An average Chicago household spends ~ 75%+ of its energy budget on NatGas and 25% on electricity.  Accordingly, on a blended basis, a Chicago household produces ~ 1.35 pounds of carbon per kWh of energy.

34)  Will Ellis Passivhaus employ natural gas for heating, hot water, clothes drying or cooking? If not, why not?

No. Ellis Passivhaus is 100% electric and the inside is not even piped for natural gas, but a natural gas hook-up remains on the property.   While natural Gas is at least 80% less expensive than electricity, it also produces about 33% more carbon.  All else equal it's significantly less expensive to heat, cook, and produce hot water with natural gas.  However,  the use of electric heat pumps significantly reduces this expenditure gap because heat pumps are 3-5 times more productive than the most efficient natural gas powered appliance.  Ellis Passivhaus will deploy heat pumps for heating and cooling, clothes drying, and hot water production.  Going 100% electric means that 100% of the energy required by the site could be produced by site based alternatives.  In the case of Ellis Passivhaus, this ideal can be achieved.