1. High Performance Homes
Jack Cowan
cowanhouse
www.cowanhouse.com
June 27, 2013

2. What is a High Performance
Home?
• A home that has significantly improved
features to provide reductions in heating,
cooling and operational costs when
compared to existing housing, while
maintaining indoor comfort and health.
(cowanhouse)

3. Why should we build performance
homes?
• Environmental impact and ownership costs
• Our housing model is not sustainable!
– Designed around the false premise that fossil fuel
would always be cheap and available in unlimited
quantities
• Little or no consideration has been given to
environmental impact, with NO VISION of the
resulting consequences
– We don’t see or feel the immediate pain of fossil
fuel energy use…only enjoy the derived benefit
(see video Kilowatt Ours by Jeff Barrie)

4. New homes use more energy, cost
more and pollute more
• Early houses
– Small size
– Small energy loads
• Newer houses
– Larger size
– More of them (world population at 7.15B vs 2.56B in
1950)
– Huge energy loads
• Many more appliances (phantom loads)
• Central heating and air conditioning
• Clothes dryers, dish washers, exhaust

5. Houses are getting bigger
and
space per occupant has tripled!
Source: Your Green Home, Wilson, 2007
1950 vs 2004 U.S. Housing
1000
294
2340
900
0
500
1000
1500
2000
2500
House size in ft. Feet per occupant
Squarefeet
1950
2004

6. Looking forward:
• Energy from burning fossil fuel will
continue to be expensive and will continue
to pollute. Therefore:
• We need a housing paradigm change that
moves us toward energy independence by
transitioning to high performance houses

7. So, what does a high
performance home look like?

8. How do we determine a home’s
performance?
HERS Index
• Home Energy Rating System (HERS)
Index offers a quantified method of
determining relative performance, much
like EPA gas mileage ratings. Houses are
computer modeled, tested for
performance, and assigned a numerical
value.

10. What is a Net Zero Energy
Home (ZEH)?
From Wikipedia
A zero-energy building, also
known as a zero net energy
(ZNE) building, net-zero energy
building (NZEB), or net zero
building, is a building with zero
net energy consumption and zero
carbon emissions annually

11. Net Zero Energy Home
vs Zero Energy Home

12. So, how do performance
houses impact?
• Environment • Total Cost of
Ownership (TCO)

13. Habitat Home on Pershing vs
existing home and new standard home
0
2
4
6
8
10
12
Existing New Std Habitat
Tons/Yr CO2
CO2

14. Habitat Home on Pershing vs
existing home and new standard home
0
10
20
30
40
50
60
70
Existing New Std Habitat
Sulfur Dioxide
Nitrogen Oxides
Lbs/yr

15. Habitat Home on Pershing vs
existing home and new standard home
$0
$500
$1,000
$1,500
$2,000
$2,500
Existing New Std Habitat
utitility cost
utitility cost

16. Increased Market Value
• EPA funded study by ICF Inc. suggested
that with every $1 reduction in annual fuel
bills, home value should increase from $10
to $25
Source: Evidence of Rational Market Valuations for Home Energy Efficiency, Nevin
and Watson, The Appraisal Journal, Oct 1998

17. Cowanhouse Hi-Performance Requirements
for new homes
–Informed Occupants – Imperative!
Includes knowledge of sustainability and
healthy indoor environments, as well as
knowledge of the financial,
environmental and operational impacts
of high performance buildings. The
ultimate QA.

18. Cowanhouse Hi-Performance Requirements
for new homes
–Site Optimization – Solar & shading
orientation (can save as much as 10%
on htg/clg), water management, and
minimal environmental impact. Identify
and avoid potential pollution sources.

19. SunTempering
• No or Low cost
• Elongated structure with maximized
southern exposure
• Minimized east/west glazing
• Dominate southern window exposure with
appropriate controls for winter/summer
solstice
• Designed passive gains and mass
consideration

20. Look at sun strike on windows
Aug 8th
Think
about
March 20,
Sept, 22,
and Dec
21 Sun
strike

21. Cowanhouse Hi-Performance Requirements
for new homes
–Building shell – Size to minimum
needed, with design to meet functional
needs. Must provide moisture
protection, enhanced thermal resistance
and total air sealing. Plan for change!

22. Houses are getting bigger
and
space per occupant has tripled
1950 vs 2004 U.S. Housing
1000
294
2340
900
0
500
1000
1500
2000
2500
House size in ft. Feet per occupant
Squarefeet
1950
2004

23. Cowanhouse Hi-Performance Requirements
for new homes
–Heating, Ventilation and Air Conditioning
(HVAC) – Passive gains, conditioned
envelope located air distribution
systems, highest performing equipment
that budget will support. Controlled and
scrubbed fresh air intake.

24. Reduction in total heating and cooling load
achieved by moving ducts inside the building’s
conditioned space. 36.4%

25. Cowanhouse Hi-Performance Requirements
for new homes
–Other – Daylighting, performance
lighting, high performance water heating
and appliances, and optimally, solar PV
and solar water heating.

26. Do these performance features
really work? Case study: FRZEH
• Case study: FRZEH (Fats’ and Reeda’s Zero
Energy Home), located in Atwood, TN,
completed in January 2009
• Now (April 25, 2013) 62,397 pounds of CO2
emissions have been offset by photovoltaic
(PV) energy production on this zero energy
home.

27. Feb
March
Does it work?

28. Thanks!
• Discussion?