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House as a System: Advanced Building Science

Presented by:Gregg Robinson, Residential Technical Specialist

Energy Trust of Oregon New Homes and Products, Technical School Outreach

July 2009

Introduction

• You are here because…

• I am here because…

You Are Here Because…

• You are interested in green building standards and codes

• You are interested in green construction practices

• You are interested in solar technologies and practices

• You are interested in sustainable materials and resources

• You are interested in learning about indoor air quality

• You are interested in green career opportunities

Energy Trust of Oregon

MissionTo change how Oregonians produce and use energy by investing in efficient technologies and renewable resources that save dollars and protect the environment

Over $5.5 million cash back to customers in 2007!

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Energy Trust Funding Structure

Utility Customers

3% Public Purpose Fund

Portland General Electric Pacific Power

Northwest Natural Gas Cascade Natural Gas

Energy Trust of Oregon

Energy Trust Service Areas

Energy Trust ProgramsEnergy Trust of Oregon

Home Energy Solutions Business Energy Solutions Renewable Energy Programs

Home Energy Review

Home Performance with ENERGY STAR®

Multifamily

EnergyTrust of Oregon’sNew Homes Program

New Homes and Products

New Homes Products

Trade Ally

Technical Education

Technical School Outreach

ADPPA, Solar

Lighting

Appliances

Manufactured Homes

Sustainable Communities

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Technical School Outreach (TSO)• Learning tools including lesson plans, and classroom and field-

based workshops for students and instructors

• FREE builder support, certification and incentives for school-built new home projects

• FREE marketing and PR support to promote your innovative program and projects

• Green Building Fund Scholarship, dedicated for TSO participants

• Access to the industry, leading experts, trainings and resources

• Advocacy and support, working with the educational community, (OR Dept. of Education, OR Dept of Community Colleges and Workforce Development) to support the development of Green Collar and Clean Tech career pathways and programs

The Basics:Energy and Building Science

Fundamentals

Think ‘Energy’

Space Heat ing3 4 %

Elect r ic A C11%

R ef rig erat or8 %

W at er Heat ing13 %

A pp liances & Light ing3 4 %

US DOE: Energy Efficiency and Renewable Energy

Energy usage in the average home

Heating System Efficiencies

Gas furnace

• 80% efficient $1.00 in = $0.80 out

• 95% efficient $1.00 in = $0.95 out

Heat pump (At Outdoor Temp of 47°F)

• 200% efficient $1.00 in = $2.00 out

• 250% efficient $1.00 in = $2.50 out

Electric resistance

• 100% efficient $1.00 in = $1.00 out

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Electricity Generation in Oregon

• Coal 6.9%

• Oil 0.1%

• Gas 26.2%

• Other Fossil Fuels 0.1%

• Biomass 1.4%

• Hydro 64.1%

• Wind 1.2%

Think ‘Heat’

Portland

• $580/year for heating

• $115/year for cooling

Bend

• $760/year for heating

• $120/year for cooling

Energy Concepts - A Quick Review

British Thermal Unit (Btu)

• A basic measure of heat (energy vs power)

• The heat required to raise one pound of water 1°F

Btu =A kitchen match contains about one Btu of heat energy

Btu Equivalents

• Watt-hour (Wh) 3.412 Btu

• Killowatt-hour (kWh) 3,412 Btu

• Propane (gallon) 91,500 Btu

• Therm of natural gas 100,000 Btu

• Heating oil (gallon) 140,000 Btu

• Cord firewood 20,000,000 Btu

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Energy In = Energy Out

Law of Conservation of Energy

• Energy is not created or destroyed, it merely changes form and moves from place to place

Second Law of Thermodynamics

• Heat moves from higher temperature regions to lower temperature regions

Consider Heat LossInstantaneous heat loss

An example: a home loses 20,000 Btu/Hour at an indoor temperature of 70°F and outdoor temperature of 30°F

• The heating system adds 20,000 BTU/Hour to maintain 70°F

• The larger the temperature difference between the inside and outside, the bigger the number

Annual (or seasonal) heat loss

An example: a home loses 50,000,000 BTU/year

• The heating system adds 50,000,000 BTU to heat the home

Heat TransferTypes of heat transfer:

• Conduction

• Convection

• Radiation

• Mass transfer (air leakage)

No matter what type of heat transfer:

• There must be a temperature difference

• Movement is always from hot to cold!

• Never ‘up’ or ‘bottom to top’

Where Do Homes Lose Heat?

Attic

Windows/Doors

Walls

Floors

Air Leaks

Air Leaks

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The Question…How to reduce heat loss?

ORHow to construct buildings to resist heat loss?

Yikes!

The Answer…

Build the house so it does not lose heat?

• Maybe we can’t do that...

• Build the house so it loses less heat?

Reduce heat loss with better thermal barrier and

insulation

Basics of Heat Loss

Four primary means of heat loss

• Conduction

• Convection

• Radiation

• Mass transfer (air leakage)

Conduction

• The transfer of thermal energy from one side of a solid object to another.

• Through multiple solid objects that touch.

• An object or objects do not have to be warm or hot for conduction to occur, only a temperature difference must be present.

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Conduction Through a Solid Surface

Warm Cold

Solid Wall

Convection

• The transfer of thermal energy from a fluid flowing over a solidobject.

• Air is a fluid.

Convection

ColdHot

Stud Cavity

Convective Loop

Convection in Other Places

ColdHot

Stud Cavity

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Radiation

• Heat transfer away from an object by means of “electromagnetic waves”or “infrared” waves

• This process involvesonly the molecules of the substance radiating the heat

Radiant Heat Transfer

Stud Cavity• Heat transfer from one surface to another

Mass Transfer

• Engineering term for air leakage

• Gaps and cracks leak conditioned, indoor air and allow “undesired” air to replace it

• Infiltration and exfiltration

Air Leakage

ColdHot

Stud Cavity

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Everybody Now!

Stud Cavity

Stud CavityMake it Stop

Convection and radiation in an insulated and

air sealed wall cavity

= Conductive Wall

BAM!Air-sealed at framing / sheathing

interface

Hot Cold

Interior Exterior

Insulation

Advanced Building Science:Applying the House as a System Approach

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OccupantsOccupants

BuildingBuilding

EnvironmentEnvironment

Mechanical Mechanical SystemsSystems

MoistureMoisture

Heat lossHeat lossPollutantsPollutants

Fire safetyFire safety

ComfortComfort Operating costOperating cost

The House as a System Approach… Components of a Building Shell

• Framing

• Insulation

• Sheathing

• Siding

• Sheet rock

Components of a Building Shell

Cans - not a recommended sheathing

Components of the Building Shell

Vulcanized foundations?

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Changes in Home Construction

• 1950s

• 1970s

• 1990s

• Now

• Better

R-Value and U-Factor (U-Value)

R-Value is used to measure thermal resistance

• R-value: the bigger, the better

• The higher the R-Value, the more resistant to heat transfer

U-Factor is used to measure thermal conductivity

• U-Factor: less is more

• The lower the U-Factor, less conduction is possible

• Definition: U-Factor is a measure of how much heat transmits through a 1 ft2 cross-section per hour when a 1° temperature difference exists between two opposite surfaces.

R-Value and U-Factor (U-Value)U-Factor is the inverse of R-Value

U = 1 ÷ R

R-Value is the inverse of U-Factor

R = 1 ÷ U

Example: Window

U-Factor - 0.38

R-Value - 2.60

Example: Fiberglass batt

U-Factor - 0.05

R-Value - 20

R-Value and 1 Divided by R-Value?

• R-Values can be added through an assembly

• R-Values cannot be averaged over an area

• U-Factors can be averaged over an area

• U-Factors cannot be added through an assembly

• Why?

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R-Value and U-Factor (U-Value)• R-Values can be added through an assembly

R-Values cannot be averaged

= R-21.4 Wall R-Value

Insulation (R-21)Drywall (R-0.4)

Rinsulation + Rdrywall = Rtotal

R-21 + R-0.4

R-Value and U-Factor (U-Value)

U-Factors can be averaged over an area

UA1 + UA2 = UAtotal

U-Factors cannot be added through an assembly

What is the overall R-Value?

R-6 StudsR-21 Insulation

77 ft2 of wall is insulation (R-21)23 ft2 of wall is framing (R-6)

So, we’ve got this wall…

Overall R-Value

5.17100

1381617100

6232177

=

+=

×+×=The easy way is wrong

R-Value and U-Factor (U-Value)

075.0100

5.71008.367.3

8.32361

67.377211

2

1

==

×=+

=×=

=×=

total

total

U

U

UA

UA

R-6 StudsR-21 Insulation

77 ft2 of wall is insulation (R-21)23 ft2 of wall is framing (R-6)

3.13

1

=

=

avg

Totalavg

RU

R

Let’s try this again…

UA1 + UA2= UAtotal

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NFRC Window Sticker R-19 Fiberglass Batt

The Energy Saver?

Saving energy for insulation installers everywhere!

What is U-0.075 and R-13.3?

U-Value is a measurement of how much heat conducts through a surface.

• Number of Btus per hour that will travel from one side of the surface to the other, per square foot of surface area at a temperature difference of 1° F.

• If there is a 1-degree temperature difference between inside and outside the house, the inside needs 0.075 ‘matches’ per square foot of wall to maintain the inside temperature.

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Replacing Lost Heat

300hrBtu

F40100ftFfthr

Btu0.075hrBtu

ΔTAUhrBtu

o2o2

=

××××

=

××=

So, we have a wall, 100 ft2 with a 40° temperature difference.

R-Value Recap

• Resistance to heat transfer

• The bigger the R-Value, the greater the resistance to heat transfer

• If you want the definition:

BtuhrFft o2 ××

Pop Quiz

How do we reduce heating bills?

a) Make a normal house with a really efficient (and possibly expensive) heating system

b) Build this house but put in really efficient windows

c) Put in lots of attic insulation because heat rises

d) Make the house so it doesn’t need much heat

Advanced Building Science: Applications and Practices

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Fancy Contraptions to Save Energy

High efficiency equipment

• After building an inefficient house?

$20,000 for windows

• Show me the pay-off in 10 years?

Infrared heating

• Heat only one side of your body?

Insulating paint

• Just like the stuff on the Space Shuttle?

Simple Contraptions to Save Energy

• Air sealing (spray foam, caulk)

• Complete/continuous insulation

• Re-locate heating systems

• Common sense

Ah Ha!

• If you reduce the need for energy, you don’t need fancy contraptions to reduce energy use!

• In our climate, this equates to reducing heat loss from the house.

What Affects the Amount of Heat Loss?

R-Value of components

• U-Factor of components

Surface area of those components

Temperature difference through those components

Amount of air leakage

• High R-Values do not guarantee low air leakage

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U-Value CalculationsTypical wall

Covered with:

• Sheet rock

• Plywood/OSB sheathing

• Siding

These are thermal bridges, providing a path for heat to conduct

Built with:

• 16” OC

• 77% Insulation

• 23% framing (thermal bridges)

The Oregon R-21 Wall

DrywallR21 Insulation, framing

Plywood/OSB

Siding

Exterior air film

0.17Exterior air film

16.7Total

0.81Siding

1.32OSB/plywood

13.3Insulation/framing

0.45Drywall

0.68Interior air film

R-ValueBuilding MaterialInterior air film

Wall U-Values

Walls consist of:

• Framing

• Insulation

• Sheathing

• Siding

• Sheet rock

• And…

Plumbing and Electrical

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Thermal BridgingWhen conductive materials are touching one another, heat flows

rapidly through the building shell

Thermal Bridging - IR

The Oregon R-21 Wall

The Oregon R-16.7 Wall

The Oregon R-14.5 Wall

The Oregon Floor

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Photo Courtesy: ©2004 Iris Communications Inc.

Insulated Floor Oregon R-30 Code Floor

• R-30 between floor framing members

• Sub-flooring

• Wood or carpet flooring

• R-28.5 (if perfect)

• R-20 – R-25 (typical)

Thermal Bridges

AtticsOregon R-38 Attic Standard Practice

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Minimal Spaces Near Eaves

R-38 turns into R-33

R-38 R-33

Air Leakage

How much air leakage?

• Run a blower door test

What is an ‘air change’?

• Blower-door test – ACH @ 50Pascals

• Average for Oregon

• 6.5 ACH @ 50 Pascals

• 0.32 Natural ACH

Air Leakage

Case Study House

• Volume = 2000 ft2 x 9 ft (ceiling) = 18,000 ft3

• CFM = 0.32 x 18,000/60

• CFM = 96 = Natural air leakage rate

60VolumeACHCFM ×

=

Energy in Air

• Each volume of air has a certain amount of energy

• Each volume of air that leaks from the house is lost energy from the house

• Energy must be added for each volume of air that leaks into the house

• Each volume of air that leaks from the house is replaced by air from outside, crawl space, attic or garage

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Calculated Heat Loss From Air Leakage

BTU/hr of energy loss

= CFM x ΔT x .018

Total Energy Losses

Conduction

• Walls

• Windows/doors

• Ceiling

• Floor

Air Leakage

Potential for Energy Loss? Oops

• Don’t forget duct losses

• Add another 20% onto that number

• At least 20% (Note the last slide)

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Where is Most Heat Lost?

4147 Btu/hr

40o

30o avg

96 CFM

Air Leaks

(0.32 ACH)

6020 Btu/hr

47o

23o Outdoor

366 ft2

0.35

Windows

6280 Btu/hr

47o

23o Outdoor

1937 ft2

1/14.5 = 0.069

Wall

30o

40o Crawl35o

35o Attic∆T70o Indoor

3750 Btu/hr

1170 Btu/hr

1112Btu/hr

Heat Loss Rate

975 ft21025 ft2Area

1/25 = 0.04

1/32 = 0.031

U-Value

Duct Losses

FloorAttic

How Much Heat Do We Need?About 22,500 Btu/hr

On the statistically coldest day

• 90 AFUE furnace

• 100,000 Btu/Therm

• $1.40 per Therm

• About $8.40 for 24 hours

• Electric Resistance Heating (no ducts)

• 3,412 Btu/kWh

• $0.08 per kWh

• About $10.60 for 24 hours

Energy Modeling Programs

• REM/Rate

• eQuest

• Energy Gauge

• WrightSoft

• Elite HVAC

• HomeCheck

Computer Models

22570376042106030628011701120Calculated

29600122004900550052001200600Modeled

(REM)

TotalDuct

lossesAir

leakageWindowsWallsAtticFloors

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Why a Larger Furnace?

Setback temperatures

• Example: Raise temperature from 60oF to 70oF

Future expansion

Air flow for air conditioning

How Can Heating Load be Reduced?

Reduce heat loss

• Stop air leaks

• Add insulation

• Bring ducts inside

Start with the architect or designer!!!

Let’s Build a House!

• Low air leakage

• Ducts inside

• Strong envelope

• Efficient heating system

• Nice mechanical ventilation

What is the Priority?

Walls? Windows? Air sealing?

Q: What is cheap and easy?

Hint: It saves a lot of energy!

Air sealing!

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Air Sealing Priorities

1. Align air and thermal barrier

2. Garage and other band joists

3. Walls behind showers/tubs

4. Wall behind fireplace

5. Attic knee-walls

6. Skylight shafts

7. Cantilevered porches/floors

8. Staircase walls

9. Shafts (mechanical/electrical/etc)

10. Plumbing/electrical penetrations

11. Dropped ceiling/soffit

12. Recessed lighting

13. Common walls between units

14. Tongue and groove sub-flooring

15. Caulk under bottom plate

Air Sealing Target

Reduce air leakage by 30 – 70%

Cantilevered Floors Rim and Band Joists

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Common Walls Install Insulation Properly

Improved Wall Systems

• Typical Oregon wall is approximately R-14.5

• Let’s improve the overall to R-24 or better

Comparing Performance R-25 16” OC

• U-Value = 0.048• R-Value = R-21

R-30 16” OC• U-Value = 0.044• R-Value = R-22.7

R-38 16” OC• U-Value = 0.035• R-Value = R-28

R-25 24” OC• U-Value = 0.047• R-Value = R-21

R-30 24” OC• U-Value = 0.042• R-Value = R-24

R-38 24” OC• U-Value = 0.034• R-Value = R-29

Insulation must be installed properly to achieve performance!

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Insulate Thermal BridgesRigid insulation on exterior provides a continuous thermal break

Great Insulation, but…

Add 1” Rigid Insulation

• About $1 per square foot

• R-5 per inch

• Properly insulated Oregon wall improves to R-22

• Removes most thermal bridges / weak points in wall

Staggered Stud Wall2x6, 2x8, 2x10 plate options

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Staggered Stud R-Values of Staggered Stud

2 x 6 12” OC

• R-22 Cavity Fill

2 x 8 12” OC

• R-30 Cavity Fill

2 x 10 12” OC

• R-38 Cavity Fill

R-19.3

R-26

R-33

Improved Window U-Values

• Code – 0.35 U-Value or lower

• ENERGY STAR – 0.32 U-Value or lower

• If you are building a better wall construction: U-0.30 or better

How to: Bring the Ducts Inside

• Move the ducts and air handler to conditioned space

• Turn unconditioned space to conditioned space

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Web Joists Trusses for “Internal” Ductwork

Energy Design Update, March 2001

End-on view of the plenum truss, built by Space Coast Truss. The plenum, which is airtight, was faced with 1/16-inch Thermoply. Only

the sides of the plenum were insulated with batts. The rest was insulated to R-19 with blown-in fiberglass.

Duct Distribution System Design Dropped Ceiling/Soffit

Drawing courtesy of www.homeenergy.org

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Source: www.eleanor.com

Dropped Ceiling Soffits Unvented Crawl or Short Basement

Photo Courtesy of: http://www.buildingscience.com

Conditioned Attic

Photo Courtesy of: http://www.buildingscience.com

Best Practice- Air Handler Installation

Use properceiling returns

Air Handler locatedcentrally in conditioned

basement

Return delivered directly to air handler

with or withoutducting

Supply runs integrated into open web floor trusses or i-joist with engineeredduct punch-out

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Best Practice- Air Handler Installation

Return delivered directly to air handler with or without ducting

Supply runs integrated into open web floor trusses or i-joist with engineeredduct punch-out

Air handler placed centrally on middle floor in conditioned space, insulate enclosure walls

Best Practice - Air Handler Installation

Use proper ceiling returns

Air Handler inConditioned attic

Best Practice - Air Handler Installation

Supply runs integrated into open web floor trusses or i-joist with engineeredduct punch-out

Air Handler placed centrally on highest floor in conditioned space, insulate enclosure walls

Return delivered directly to air handler without ducting

Central Air Handler – 2-Story Home

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Ductless Heat Pumps

Photo: Jeff Pratt

Ductless Heat PumpsSome other heads

Mounts flush to the ceilingThese are not small –

2’ x 2’ – 3’ x 3’

Goes above the ceiling.You attach a short duct run to it.

A below-window radiator

Ductless Heat Pumps Ductless HP Efficiencies

7.7 – 9.5 HSPF

• 200 – 300% efficiency

• At 47 degrees

• Reduced efficiency as outdoor temperature falls

• Don’t buy cheap units

• Inverter driven

• Most important…

• From Asia

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Other Benefits for Bringing Ducts Inside

• Smaller heating plant

• Shorter duct runs

• Not as much crawl space or attic work for install or maintenance

• Improved air flow (smaller duct runs)

Floor and Attic Insulation

• R-50 attic insulation with raised heel truss

• R-38 under floor insulation

Remember This!

• Learning curve

• Different material needs i.e. engineered joists

• Suggest using metal duct

• Involve multiple trades in design process = Integrated Design

• Architect/Designer

• HVAC

• Framer

Mechanical Ventilation

• ASHRAE 62.2

• 7.5 CFM per occupant (#bedrooms +1)

• Plus 0.01 CFM per square foot

( 3 + 1 ) x 7.5 + 2000 x 0.01

= 50 CFM

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Heating Energy Use After Improvements

1512 Btu/hr

40o

30o average

50 CFM (70%Recovery)

Mech. Ventilation

1944 Btu/hr

40o

30o

average

45 CFM

Air Leaks(0.15 ACH)

5160 Btu/hr

47o

23o

Outdoor

366 ft2

0.30

Windows

3450 Btu/hr

47o

23o

Outdoor

1937 ft2

1/26 = 0.038

Wall

30o

40o

Crawl

35o

35o

Attic

DT70o

Indoor

0 Btu/hr

848Btu/hr

717Btu/hr

Heat Loss Rate

975 ft21025 ft2Area

1/38 = 0.029

1/50 = 0.02

U-Value

Duct Losses

FloorAttic

Heat Loss Comparison

1512 Btu/hr

Mech. Ventilation

1944 Btu/hr

4147 Btu/hr

Air Leaks(0.15 ACH)

5160 Btu/hr

6030 Btu/hr

Windows

3450 Btu/hr

6280 Btu/hr

Wall

3750 Btu/hr

1170 Btu/hr

1120Btu/hr

Code Home

0 Btu/hr

848Btu/hr

717Btu/hr

Improved Home

Duct Losses

FloorAttic

Now, How Much Heat Do We Need?

• 13,630 Btu/hr at 23oF

• REM/Rate 12,900 Btu/hr

Code vs. Improved Home

HeatingHeating

Lights & Appliances Lights &

Appliances

WaterWater

Cooling

Cooling

Improved HomeCode Home

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Envelope Upgrade CostsWall Upgrade

• 2x8 Staggered Stud

• R-30 Low Density Foam Insulation

• About $2/ft2 upgrade

• $8,000 upgrade cost

Floor Upgrade

• R-30 to R-38 Joisted Floor

• About $0.20/ft2 upgrade

• $200 upgrade cost

Attic Upgrade

• R-38 to R-50 Raised Heel Truss

• About $0.20/ft2 upgrade

• $200 upgrade cost

Window Upgrade

• U-0.35 to U-0.30

• $1/ft2

• $400 upgrade cost

Envelope Upgrade Costs - Alternates

Blown-in Blanket Upgrade

• $1,500

• Plus framing upgrade cost $1,600

Advanced Framing with 1” Exterior Rigid Foam Upgrade

• $2,000

Air Sealing Upgrade Costs

• Pay attention to air sealing at crawl space and attic connections, electrical boxes, hatches, garage, other penetrations!

• No tongue and groove sub-flooring

• $100

HVAC Upgrade Costs

• Duct sealing $400

• Ducts inside $800

• Heat recovery ventilator $2,000

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Total Upgrade Costs

• Envelope $4,000 - $9,000

• HVAC $500 - $3,200

• Air sealing $100

Total Investment = $5,000 - $11,000

Computer Modeling Results

Code Home

• $1,556 per year utility costs

Improved Home

• $1,220 per year utility costs

• Utility savings $336 per year

• Mortgage increase per year $720 ($10,000 @ 6.0%)

• Mortgage increase per year $360 ($5,000 @ 6.0%)

Alternate

Advanced Framing with ½ inch foam (not as air tight)

• Energy Costs: $1,295 per year

• Savings: $261per year

Advanced Framing with no foam (typically fiberglass batts installed)

• Energy Costs: $1,353 per year

• Savings: $203 per year

What is the Incentive?State Tax Credits

High Performance Home

• R-49 Attic (U-0.30)

• U-0.050 Walls

• U-0.025 Floors (R-38 between joists)

• U-0.32 Windows - Glazing limited to 16% Window : Floor ratio

• Shell tightness < 5.0 ACH50

• HVAC

• Efficient water heating

• Renewable energy system

• Additional Measure

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Energy Trust Incentives

Energy Trust of Oregon Incentive Levels

• ENERGY STAR $800

• ENERGY STAR + Ducts in Conditioned Space + $800

• State HPH envelope, HVAC, DHW requirements + $800 (all but renewable and additional measure)

• + Renewable energy (solar hot water and/or PV) ++++++

• Net Zero ++++++

High Performance HomeIntroductory Oregon High Performance Home meets all requirements (except renewable energy system and additional measure):

• $2,400 from Energy Trust

• $2,000 Federal Tax Credit

High Performance Home is currently hard to meet with electric heating systems (including heat pumps)

Advanced High Performance Home, with renewable energy (solar hot water or PV):

• $2,750 from Energy Trust (with solar hot water)

• More $$$’s with PV or other advanced energy performance measures

Oregon High Performance Home Tax Credit for Builders up to $12,000

http://oregon.gov/ENERGY/CONS/BUS/docs/HPH_handout.pdf

I Want to Build a “Net Zero” Home

Design and build the home we discussed. Add:• Better windows• Improved Air Sealing (Make the home really tight)• Really efficient heating system

Add renewable energy

Turn off the lights and phantom loads• Educate homeowners

Online Resources

www.energystar.gov/index.cfm?c=tax_credits.tx_index

ENERGY STAR, Federal Tax Credits

www.energytrust.org/ESNHENERGY STAR® New Homes

www.energystar.govEPA ENERGY STAR®

www.eere.energy.govU.S. Dept. of Energy Energy Efficiency and Renewable Energy

www.buildingscience.comBuilding Science Corporationwww.usgbc.orgUS Green Building Council, LEED for Homeswww.earthadvantage.comEarth Advantage™

www.energytrust.org/TA/hes/index.html

Home Energy Solutions, Existing Homes

www.energytrust.orgEnergy Trust of Oregon, Inc.

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Online Resources - Continued

www.efficientwindows.orgEnergy Efficient Windows Collaborative

www.lightingplans.comEnergy Efficient Lighting

www.bpi.orgBuilding Performance Institute

www.natresnet.orgResidential Energy Services Network (RESNET®)

www.oregon.gov/ENERGY/CONS/BUS/BETC.shtml

Oregon Department of Energy, Business Energy Tax Credits (BETC)

www.oregon.gov/ENERGY/CONS/RES/RETC.shtml

Oregon Department of Energy, Residential Energy Tax Credits (RETC)

www.oregon.gov/ENERGYOregon Department of Energy (ODOE)

Print Resources• Brand, Steward. How Buildings Learn: What Happens After They’re Built New York:

Penguin Books, 1995.• Burnett, John F. and Eric F.P Straube. Building Science for Building Enclosures

Westford: Building Science Press, 2005. • Carmody, John, Stephen Selkowitz, Dariush Arasteh and Lisa Heschong. Residential

Windows New York: Norton, 2007.• Harley, Bruce. Insulate & Weatherize: Expert Advice from Start to Finish (Build

Like a Pro) Newton: Taunton, 2002.• Krigger, John and Chris Dorsi. Residential Energy: Cost Savings and Comfort for

Existing Buildings (4th Edition). Helena: Saturn, 2004. • Lstiburek, Joseph, PhD. Builder’s Guide to Mixed-Humid Climates Minneapolis:

EEBA, 2005.• Lstiburek, Joseph W., PhD. Water Management Guide Building Science Press, 2006.• Rose, William B. Water in Buildings: An Architect’s Guide to Moisture and Mold

Wiley, 2005• Wilson, Alex and John Abrams. Your Green Home: A Guide to Planning a Healthy,

Environmentally Friendly New Home Gabriola Island, BC: New Society, 2006.

High Performance Walls

• Rain Screens

• Advanced Framing: Basic and Intermediate

Rain Screen Walls

Fine Homebuilding, February/March 2001

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Code Corner: Advanced Framing 24” O.C.

Allowed for 2x6 and 2x4 Wall Construction

Advanced Framing

• Advanced framing saves money, lumber and energy

Drywall Clip

Standard Frame: R-13.6 Advanced Frame: R-16

18% Improvement at less cost

Reducing Framing Materials, Thermal Bridging through Advanced Framing Standard Frame: Exterior Corner Detail

Walls are commonly framed in a way that does not allow insulation to be installed at exterior corners

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Advanced Frame: Alternate Exterior Corner Detail

Source: Builders Guide to Cold Climates, Lstiburek. 2005

Standard Frame: Interior - ExteriorWall Intersection DetailWalls are commonly framed in a way that does not allow insulation to be installed at interior – exterior wall intersections

Photo ©2008 CSG

Standard Frame: Interior – Exterior Wall Intersection

Advanced Frame: Alternate Interior-Exterior Wall Intersection Detail

Source: Builders Guide to Cold Climates, Lstiburek. 2005

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Photo ©2008 CSG

Advanced Frame: Insulated Wall IntersectionFrame wall intersections to allow for full insulation installation

“Intermediate” Advanced Framing

• Raised Heel Truss

• Strapped Walls

• Stagger Studs

• 2’ grid layout of window and doors openings

Advanced Framing: Raised Heel TrussBuilt up truss to allow for full depth insulation to extend to roof/wall intersection.

Photo ©2008 CSG Photo ©2008 CSG

Roof and Wall Intersection DetailsFoam blocking set to be foamed in place for an air tight seal

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Advanced Framing: Strapped WallsSpray in cellulose insulation with 2x strapping over studs reduces thermal bridging through the wall assembly.

Photo courtesy Mike O’Brien, City of Portland Office of Sustainable Development 2007

Resources: Advanced Framing, High Performance Wall

Energy and Environmental Building Association (EEBA)

2008 Annual Conference Presentations

http://www.eeba.org/conference/2008/sessions.htm

• Valuing Energy Efficiency in the Marketplace

• Thermal Metric for High Performance Enclosure Walls: The limitations of R-Value

• The future of Framing is Here: Case Study Advanced Framing

• Building America Special Research Project: High R-Walls Case Study Analysis