What does a 90% REduction in Building energy Demand for heating and cooling mean?

To reverse the trajectory of global warming and avoid mass extinction, man made CO2 emissions must be radically reversed. Every building requires an amount of energy to maintain a given level of comfort. For a Passivhaus Institut (PHI) Certified Building this means a temperature range of 68 F to 77 F for 90% of the hours in a given year, among other factors. In most climate zones most of the energy required goes to heating or cooling requirements and a relatively small proportion goes to lighting and appliance uses. While many municipal energy grids rely on carbon energy sources for 100% for their uses, Chicago depends on carbon energy fuels for approximately 90% of its energy requirements. Further, the Mayor’s Office reports that some 73% of Chicago’s CO2 emissions result from powering its commercial, residential, and institutional buildings and as a signatory to the C 40 Cities Accord, Chicago has committed to eliminating total annual CO2 output by some 80% and over 25 million tonnes by 2050. Any PHI Certified Building results in a 90% reduction all else equal and therefore significantly reduces CO2 emissions for a given building all else equal. On direct comparison with a nearly identical vintage Greystone, Ellis Passivhaus expects to eliminate some 200,000 pounds of CO2 emissions per year while providing superb comfort.


1)  The preeminent global standard in healthy and energy efficient building design.

2)  A scientifically based, empirically driven building methodology proven to reduce building energy demand and provide unsurpassed indoor comfort and air quality as proven through tens of thousands of examples located around the world - every climate zone and continent from Qatar to Antarctica. 

3)  An actual building (a "passive" "house," "school," "office," "clinic," "townhouse," "condo"... )

4)  A growing lifestyle movement,

5)  A moral and economic choice.

"Passivhaus" is a set of concepts, values and standards established and maintained by the Passivhaus Institut and International Passive House Association.  

what does A "passivhaus" Building achieve?

Existing buildings leak air and with air leakages significant losses of heating and cooling energy and, the infiltration of dust, pollen, and other pollution occurs.  A Passivhaus Institut (PHI) Certified  building achieves a 90% reduction in energy demand for heating and cooling principally by plugging the average of two (2) miles of gaps and cracks that plague most existing buildings. It also delivers pristine indoor air quality.   Other building components like heat pumps and on-site solar PVs enable a Passivhaus Institut Certified Building building to achieve energy (grid) independence in many cases - even in urban environments.

The Passivhaus Institut Building Standard in a Nutshell

  1. PHPP:

    • Passivhaus Planning Package Model

  2. Renovation:

    • 7.92 kBTU PSF/YR for heating and cooling and

    • 1.00 ACH at Pascal 50

  3. New Construction:

    • 4.75 kBTU PSF/YR for heating and cooling and

    • .60 ACH at Pascal 50

"kBTU PSF/YR"  -- thousand BTU (British Thermal Unit) per square foot per year.

"ACH" -- air changes per hour under pressure of Pascal 50 ("50 Pascals").  A Pascal is a standard unit (SI) of atmospheric pressure.  "50 Pascals" approximates the pressure of a 20 MPH wind.  A blower door test measures the infiltration and exfiltration, or ACH, of the building in questions under 50 Pascals of pressure.

The process begins with a PHPP model of the site and building. With new construction, building design and orientation adjustments generally occur to maximize passive solar gain. In renovation, since the building location is already defined, the PHPP serves as an iterative tool to define insulation sufficiency and potentially as a design tool to enhance passive solar gain.  In both cases the combination of solar gain, insulation sufficiency, building assemblies, glazing and architectural and landscape design lead to satisfaction of the necessary conditions shown above. That's it.  Three simple and universal constraints!

  1. PHPP Model,

  2. Energy for Heating and Cooling ( kBTU/PSF/YR)

  3. Air-tightness (ACH @ Pascal 50)

The balance of these elements result in exceptional comfort, indoor air quality, and a really low energy bill.

The Passivhaus Institut Building Standard -- A major factor in reducing carbon emissions globally and REducing Global Warming.

Please consider these questions.

  1. Is global warming real?

  2. Are carbon emissions harmful to health?

  3. Can individuals and societies significantly reduce harmful air and environmental pollution?

If you answered "Yes." to one or more of these questions, you should find the following interesting.  

If you answered "No."  to any of these questions, then you should build, renovate or buy a PHI passive house just because it's super healthy, super comfortable and will save you lots of money month after month and year after year.  A PHI building epitomizes luxury and true elegance - no draughts, minimal temperature variation, acoustical separation, weather event safety and efficiency. Doing so also enhances job creation and promotes economic growth.  And, it doesn't cost more to achieve all else equal.  

Global warming constitutes an ongoing, one million+ year old process. However, credible scientific research suggests that man's adoption of carbon fuels over the past 100 years, and the resulting pronounced increase in carbon emissions, has dramatically increased the rate of global warming. Fossil fuels provide over 80% of the energy used by industrial production and by consumers for domestic and personal transportation needs. On average one unit of fossil fuel energy received from the grid produces well over one pound of carbon emissions (Nat Avg. ~ 1.5 lbs.)  An average Chicago household can easily produce 150,000 pounds of carbon per year for its domestic and personal transportation needs.  To put this in perspective, an average Chicago household hurls about 30 Ford F 150 pick-up trucks, or, 75 pallets of bricks, or, the entire 2016 US Olympic Team into the atmosphere each year.  

Mankind has in effect created a massive environmental earthquake unleashing into the atmosphere a carbon emission tsunami which serves as an insulating blanket of ever increasing size elevating temperatures at sea level.  Some scientists claim that if the average surface temperature at sea level rises by just another 1-2 degrees that a mass extinction event results. Some 49% of carbon emissions stem from industrial production and transportation while some 51% stem specifically from the buildings!  Of this, some 70% stem specifically from heating, cooling and hot water production. Add in cars and the household total rises to over 65%.  That's household heating, cooling, hot water, overhead lights, refrigeration, cooking, communications, any other domestic use, and, personal transportation. The PHI Building Standard reduces building heating and cooling demand by > 90% when compared to existing buildings and when compared with conventional new construction building methods!   

Energy use by sector and type - 

Electrical Energy Use by Major City

kWh per Year per Customer -



The thermal image (heat map) of the Chicago skyline above looks like every city across the globe.   The night sky (dark blue) represents cool temperature.  In contrast yellow hues represent heat (energy) radiating out of buildings. Suppose instead that the thermal image was entirely blue and that the building heat (energy) remained in the building.  Manmade carbon emissions would retreat to levels not seen for nearly 100 years.  

We literally don't see insidious building energy/heat loss as environmental pollution but it's staring right at you through the lense of a thermal camera.  What's the difference between insidious building energy loss and a bus belching smoke you may ask?  We can see and smell the belching smoke.  Insidious building energy loss constitutes approximately 50% of manmade carbon pollution and 70% ends up in cities inducing an array of major respiratory and related health issues.  Insidious building energy loss constitutes the single largest man made contribution to global warming and at least 90% can be eliminated by building and renovating to the Passivhaus Institut Building Standard (PHI) making it the single most impactful strategy in combating carbon emissions.

Lakeshore Drive. October 2016.

Passivhaus - 

If you're a homeowner (or would be homeowner) wouldn't it be great if you could heat your house with a candle and cool it with an ice cube?  If you're an institutional building owner wouldn't it be great to slash your energy operating expense by 80% or more per year in perpetuity?  What if an array of indoor air quality, comfort and environmental and health benefits resulted as a consequence? What if it cost less than $1.00 per day for 100% of all household energy needs?

Tens of thousands of actual  "passive houses" exist throughout the rest of the world and on every continent including Antarctica.  They come in all shapes, flavors, and uses.  The blue building above represents one of the first PHI certified buildings in the US.  Only a relative handful of passive houses of any type exist in the US today but many passive house projects are underway.  Each uses some 80 - 90% less energy than an unrenovated existing building and each provides remarkable indoor comfort and air quality.  The thermal image (heat map) immediately above shows an actual PHI  "certified" passive house renovation in Brooklyn, NY. It's a winter night.  Blue means relatively cold and yellow means relatively warm. Unlike the other buildings, the outside of this passive house is relatively cold. The energy stays inside the house due to really good windows and doors, sufficient and continuous insulation, a continuous air tight layer, the absences of thermal bridges and careful attention to detail during the construction process. Continuous balanced mechanical ventilation provides fresh filtered air while retaining 80%+ of the embedded energy through the continouse air exchange process.   


The Consumption Mix

This graphic reflects the type and quantity of energy we use at the household level.

This graphic shows where we use our energy at the sector level.

This graphic shows the composition of the energy we use by type.  Twenty rooftop PV (photovoltaic) panels and 600 SF of rooftop space can satisfy the total energy requirement of a 3500 SF single family passive house - about 10K kWH per year in Chicago.  

The greatest single action a person could take to reduce their contribution to global warming would be to live in a PHI certified "passivhaus" building because such a building requires 80-90% less energy to heat and cool and therefore that much less carbon is produced.  If the passive house in question was outfitted with PV panels that prioritized site consumption over the grid 100% of your energy needs for living including 10,000 miles in your 100% electric vehicle would be covered.

Big picture: War, terrorism, trade battles, drugs, gang violence, bad schools, wage inequality all pale in magnitude. Civilization as we understand it - perhaps even life itself, hangs in the balance. Global warming is no joke. 

let the best ideas come forward - 

Click below to learn how the world's most highly regarded, most rigorous and most energy efficient building standard is changing the world for the better.

Be Aware - 

Scientists unanimously agree that  1) we're in an ice age ("Quaternary" )and have been for the past ~ 2.6 million years,  2)  climate change is real, and 3) the planet is warming all else equal. Disagreement centers on mankind's contribution to this global warming trend as a consequence of our discretionary carbon production for energy required by industrial production and domestic heating, cooling, transportation, and everyday conveniences.

The average temperature of the earth's surface has increased by approximately 1 degree Celsius over the past 100 years. In the same period the total amount of carbon emissions produced each year has increased from 1 billion metric tons to over 10 billion metric tons each year. Coal and petroleum account for over 80% of which natural gas accounts for some 19%.  NatGas produces some 1.3 pounds of carbon per kWH.  Coal and fuel oil produce approximately 2 pounds of carbon per kWH.  Some in the scientific community claim that if the earth's surface temperature increases by another 1 degree, then life as we know it will perish.  Others say we're already in mass extinction mode.  Still others dismiss these claims as bad science.  Regardless of one's orientation, carbon emissions themselves provide negative benefits.  

A smoggy day in Harbin, a city of 11 million in northern China. Many cities in China experience such smog induced by coal fired power plants. This growth comes at the cost of a loss of 5 years of life expectancy versus southern Chinese cities due to heightened heart and lung disease due to smog. Click here.

LA in 1980 and LA recently. USC researchers concluded in a paper published in the New England Journal of Medicine that health increased as air pollution decreased over the 30 year period. Click here.

Over 50% of of all carbon emissions produced across the world stem from buildings and 70% of all carbon emissions end up in cities.  Therefore, significantly reducing carbon emissions stemming from buildings would significantly reduce carbon emissions worldwide and in cities in particular.  

Carbon emissions induce an array of major health issues and constitute man's greatest contribution to global warming.  The  Passivhaus Institut Building Standard radically reduces hydrocarbon based energy demand through building  design protocols developed and supported by extensive scientific research, thirty years of data and tens of thousands of buildings of all types and uses. 

Habitat for Humanity has built to the Passivhaus Institut Building Standard There's a $16 million dollar upper west side Manhattan townhouse coming online, several Brooklyn Brownstones, a Queens based assisted living facility and several other projects in NYC also coming online

Excellence Defined -

The following picture represents a thermal image of a passivhaus building next to a conventionally constructed building.   The Passivhaus Institut Certified Building appears as blue because heating and cooling energy stays inside.  This standard reduces heating and cooling demand by as much as 90% when compared with current new construction methods.  That means 90% less energy is demanded from the grid. Hence it's already a "Nearly Zero Energy Building"(NZEB) by definition opposed to a "Net Zero Energy Building" which could still be very inefficient, draw a great detail of energy from the grid, and hence produce a great deal of carbon.  From a NZEB starting point it becomes that much easier to become grid independent because on-site energy production is that much lower. PV (photovoltaic) panels on some 500 square feet of rooftop should do the trick most of the time in most climate zones, even Chicago. This combination not only minimizes grid draw and thus man made carbon emissions but also preserves and enhances creature comforts. Passivhaus Institut  plus PVs means household carbon emission production approaches zero.

A PHI  building, regardless of type, relies substantially on the respective occupant's own body heat (energy,) and their behaviors (TVs, lights, computers, hair dryers) because the primary heat/energy source  stays in the building.  This consequence starts with a holistic data driven engineering model titled "Passivhaus Planning Package" (PHPP) principally relying on the balance between these two major factors:  

  1. Building Envelope

    1. Thermal bridge mitigation,

    2. Continuous insulation,

    3. Continuous air barrier,

    4. Glazing

  2. Indoor Air Quality

    1. Continuous balanced mechanical ventilation with energy/heat exchange.

Pristine indoor air quality, balanced relative humidity and constant temperature among all surfaces results - 24/7/365.  A small ductless air conditioning system provides cooling and supplemental heat when required. Other benefits include acoustic separation (peace and quiet) and weather event safety.  When the grid goes down during a hurricane, earthquake or blizzard, the temperature remains relatively constant for several days.   Low energy demand and low variance of temperature and relative humidity in the first instance directly results in very low heating and cooling demand from upstream carbon producing energy sources. Other benefits include ease of operation and low operating expense due to the lack of extensive ductwork far more complicated heating and cooling systems. Occupants glowingly express that they experience comfort levels they never imagined. (See the Passivhaus Living Explained tab.)

Passivhaus Institut Certified Buildings maintain their initial performance levels over the life of the building.  Long term data sets prove this point.

An increasing number of major state and municipal jurisdictions like Brussels Belgium, Dublin, Ireland, and New York City, among others, have recently adopted Passivhaus Institut Building Standard principles and standards into their respective Building Codes.  Tens of thousands of buildings of all types including schools, assisted living, townhouses, public housing and custom homes on every continent have been built or renovated to this rigorous, data driven and third party quality assured international standard.  There's even a Passivhaus in Antarctica.

If we as a society build and  renovate to the Passivhaus Institut Building Standard total man made carbon emissions will significantly decline elevating our standard of living while creating more healthy, productive and sustainable living environments. 

Michael R Conners - Founder

Kenwood Construction Services, Inc.


International Passive House Association

Passivhaus Institut