From the Ground Up
A Review of
Residential Energy Efficiency
Joseph Laquatra
Cornell University
Energy Use in the Residential Sector
Residential Use –
21% of
U.S. energy
consumption
(27% in NYS)
Many opportunities
to d...
Applications of energy efficiency to a home can result
in substantial reductions in energy bills.
Comparison of energy use...
through the foundations walls, and upward to the surface;
downward to the deep earth;
A basement loses heat:
In new construction - many ways to
make foundation walls more energy
efficient.
One way :
insulate the exterior side of th...
Another way:
assemble foundation walls with
polystyrene forms
The forms become part of the
foundation system and insulate
...
Another way is to assemble a
foundation wall with pre-cast,
insulated concrete panels.
Continuous Drainage Plane
• Design Issues
• Micro-conditions
• Material components
• Surface & below grade
details
• Drain...
Dampproofing ≠ Waterproofing
Can’t be done
(requires water barrier
without holes)
Wood decay
No vapor retarder
below grade
Insulate rim joist
Now consider the walls of a house.
Dampness
and/or mold
Perfect wall: environmental
separator*
Keeps outside out
Keeps inside in
To do this, must control rain, air, vapor, heat
*...
Vapor Retarder
Most effective strategy
to increase energy efficiency
• Air sealing
• Attic insulation
• Improve heating/air conditioning ...
Air Leakage
Uncontrolled and/or unintended
airflow through a building enclosure
Air leakage (30% space conditioning losses)
House Wrap: Wind barrier, drainage plane
Sealants
Many homeowners can do their
own caulking, weatherstripping, and
insulating.
BUT – none of these are very
effective if the...
blower door test
duct blaster
Thermography
Details
- 24-inch OC 2X6 in-line
- 2-stud corners
- load-tuned headers
- single top plate
- minimized cripples
- open web ...
Structural Insulated Panels (SIPs)
Structural Insulated Panels (SIPs)
4 1/2" 6 1/2"
EPS 14.4 21.6
XPS 19.5 29.5
Polyurethane 21.7 32.9
Panel Thickness
R-value
Insulation Type R-Value Per Inch Made From
Cellulose 3.5 - 3.7 Ground wood or paper
Fiberglass batt 3.0 - 3.8 Strands of m...
Open cell Closed cell
Soy Based: Still has petrochemicals. USDA: 7% spray foam product
must be bio-based.
Denim batts
In wall cavities, heat is lost
through the wooden studs -a
thermal bridge. Also happens
through floor joists at wall
inter...
Thermal break: insulating material
that prevents a structural element
from acting as a thermal bridge.
Thermal Breaks
ThermablokTM : aerogel
strips
R-2.58/1/4”
After a house is sealed, the furnace or
boiler may have to be derated – it doesn’t
need to produce as much heat anymore.
O...
Usually, insulation can be added to an attic easily.
U.S. DOE recommendation
for NYS:
R 49 - 60
ENERGY STAR WINDOWS, DOORS, & SKYLIGHTS HAVE THIS LABEL.
SHADED AREA OF MAP INDICATES REGION PRODUCT IS DESIGNED FOR
ACEEE’s 2010 State Energy Efficiency Scorecard
http://www.energystar.gov/index.cfm?c=
home_sealing.hm_improvement_insulation_table
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From The Ground Up 1

  1. 1. From the Ground Up A Review of Residential Energy Efficiency Joseph Laquatra Cornell University
  2. 2. Energy Use in the Residential Sector Residential Use – 21% of U.S. energy consumption (27% in NYS) Many opportunities to decrease this.
  3. 3. Applications of energy efficiency to a home can result in substantial reductions in energy bills. Comparison of energy used in an average house in the Northeast and an energy efficient house The energy bill in the efficient home is $1,180 less than that of the average home.
  4. 4. through the foundations walls, and upward to the surface; downward to the deep earth; A basement loses heat:
  5. 5. In new construction - many ways to make foundation walls more energy efficient. One way : insulate the exterior side of the walls with rigid board insulation. Loss through basement walls
  6. 6. Another way: assemble foundation walls with polystyrene forms The forms become part of the foundation system and insulate the walls. and then fill them with concrete.
  7. 7. Another way is to assemble a foundation wall with pre-cast, insulated concrete panels.
  8. 8. Continuous Drainage Plane • Design Issues • Micro-conditions • Material components • Surface & below grade details • Drain Everything! • Weatherlapping Rules! EEBA WMG/HTWII
  9. 9. Dampproofing ≠ Waterproofing Can’t be done (requires water barrier without holes)
  10. 10. Wood decay
  11. 11. No vapor retarder below grade
  12. 12. Insulate rim joist
  13. 13. Now consider the walls of a house.
  14. 14. Dampness and/or mold
  15. 15. Perfect wall: environmental separator* Keeps outside out Keeps inside in To do this, must control rain, air, vapor, heat * Building Science Corporation
  16. 16. Vapor Retarder
  17. 17. Most effective strategy to increase energy efficiency • Air sealing • Attic insulation • Improve heating/air conditioning efficiency
  18. 18. Air Leakage Uncontrolled and/or unintended airflow through a building enclosure
  19. 19. Air leakage (30% space conditioning losses)
  20. 20. House Wrap: Wind barrier, drainage plane
  21. 21. Sealants
  22. 22. Many homeowners can do their own caulking, weatherstripping, and insulating. BUT – none of these are very effective if there are leaks in a home. MANY LEAKS CANNOT BE FOUND WITHOUT SPECIAL EQUIPMENT.
  23. 23. blower door test duct blaster
  24. 24. Thermography
  25. 25. Details - 24-inch OC 2X6 in-line - 2-stud corners - load-tuned headers - single top plate - minimized cripples - open web floor truss - insulating sheathing - modular dimensions Advanced Framing
  26. 26. Structural Insulated Panels (SIPs)
  27. 27. Structural Insulated Panels (SIPs) 4 1/2" 6 1/2" EPS 14.4 21.6 XPS 19.5 29.5 Polyurethane 21.7 32.9 Panel Thickness R-value
  28. 28. Insulation Type R-Value Per Inch Made From Cellulose 3.5 - 3.7 Ground wood or paper Fiberglass batt 3.0 - 3.8 Strands of molten glass Fiberglass loose-fill 2.2 - 3.0 Strands of molten glass Rockwool or mineral wool 2.7 - 3.0 Molten rock or slag Denim (or cotton) batt 3.7 Recycled fibers Rigid Board extruded polystyrene 4.6 - 5.0 Petrochemical Rigid Board polyurethane or isocyanurate 6.0 - 8.7 Petrochemical Open cell polyurethane spray foam 3.5 Petrochemical Closed cell polyurethane spray foam 6.0 Petrochemical Cementitious foam 3.9 Air, water, MgO
  29. 29. Open cell Closed cell Soy Based: Still has petrochemicals. USDA: 7% spray foam product must be bio-based.
  30. 30. Denim batts
  31. 31. In wall cavities, heat is lost through the wooden studs -a thermal bridge. Also happens through floor joists at wall intersections. Thermal Bridges stud
  32. 32. Thermal break: insulating material that prevents a structural element from acting as a thermal bridge. Thermal Breaks
  33. 33. ThermablokTM : aerogel strips R-2.58/1/4”
  34. 34. After a house is sealed, the furnace or boiler may have to be derated – it doesn’t need to produce as much heat anymore. Or – upgrade to an energy efficient, sealed combustion system.
  35. 35. Usually, insulation can be added to an attic easily. U.S. DOE recommendation for NYS: R 49 - 60
  36. 36. ENERGY STAR WINDOWS, DOORS, & SKYLIGHTS HAVE THIS LABEL. SHADED AREA OF MAP INDICATES REGION PRODUCT IS DESIGNED FOR
  37. 37. ACEEE’s 2010 State Energy Efficiency Scorecard
  38. 38. http://www.energystar.gov/index.cfm?c= home_sealing.hm_improvement_insulation_table

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