Energy Star Homes - Estimated Cost and Savings

8/3/2019 Energy Star Homes - Estimated Cost and Savings

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ENERGY STAR Qualified Homes, Version 3Savings & Cost Estimate Summary

The savings and incremental costs of implementing the ENERGY STAR Qualified Homes guidelines, Version3, will vary for each individual home, dependent on variables such as baseline construction practices,geographic location, house design, and vendor relationships. For example, builders may experience much

lower incremental costs where they are already using above-code windows or equipment efficiencies,complying with code-required high-quality insulation installation not currently enforced, or do not installappliances or ceiling fans within their homes.

As a means of developing illustrativesavings and costs, EPA evaluated fourteen typical homes across hot,mixed, and cold climates. Each home was a single-story detached home with 2,200 square feet of conditionedfloor area, an even width and length, 8 foot ceiling height, and three bedrooms. Window area to floor area ratiowas 15% with windows evenly distributed on all four sides of the home. Slab on grade homes were modeled inclimate zones 1 through 3, while unconditioned basements were modeled for homes in climate zones 4-8. Twohomes were modeled in each climate zone; one was configured with a gas furnace, gas water heater, andelectric air conditioner while the other was configured with an electric heatpump and electric water heater.

The energy efficiency features of the baseline homes were aligned with the 2009 IECC prescriptive path,though Grade III insulation installation was assumed for walls and Grade II insulation installation was assumedfor ceilings and floors. The assumption of degraded insulation installation reflects EPAs experience with typicalhomes built to code. The rated homes were aligned with the requirements of the prescriptive path of theVersion 3 guidelines, referred to as the ENERGY STAR Reference Design.

Because not all of the features proposed for the ENERGY STAR guidelines, Version 3, are currentlyrecognized or credited within RESNETs current implementation of the HERS guidelines, the energy savingswere estimated for each rated home using a two-step process.

First, each of the homes was modeled in REM/Rate v12.85 software with all of the features recognized byRESNETs HERS guidelines and able to be entered into the software program.

Second, improvement factors were developed to account for the impacts of the quality-control checklists thatare not currently credited in the RESNET standards (i.e., Fully-Aligned Air Barrier and Air Sealing Sections ofthe Thermal Enclosure System Rater checklist and HVAC System Quality Installation Contractor and Raterchecklists). One of these factors was accounted for using modifications to the REM/Rate inputs (i.e., 15%improvement in duct leakage, from 4.0 to 3.4 CFM per 100 sq. ft. of conditioned floor area, to account for theHVAC System Quality Installation Rater checklist). The others were accounted for by modifying theconsumption outputs from REM/Rate. First, the heating and cooling energy consumption was reduced by 15%to account for the Fully-Aligned Air Barrier and Air Sealing Sections of the Thermal Enclosure System Raterchecklist. Second, to reflect the HVAC System Quality Installation Contractor checklist, the heatingconsumption was reduced by 2.5% for combustion heating equipment or by 5% for electric heatpumps and thecooling consumption was reduced by 5% in all homes. More details about each of these improvement factorsis included in the supporting savings and cost summary for each of the checklists, at the end of this document.

Incremental costs were estimated for each of the features required by the ENERGY STAR Reference Designas applied to each of the fourteen homes and then summed across all features.

Exhibit 1 on the following page contains a summary of the incremental costs and purchased energy savings foreach home, along with the resulting cashflow. Exhibits 2 through 15 contain a breakout of the cost estimate foreach of the fourteen homes. This is followed by the supporting savings and cost summary for each of thechecklists.


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Exhibit 1: ENERGY STAR Qualified Homes, Version 3 Illustrative Cost & Saving

Savings

Home CZ Location Stories Foundation

HVAC

Equipment Type Heating Fuel

2009

IECC

ENERGY

STAR

Version 3

ENERGY

STAR

Version 3 Total C

1 1 Miami, FL One-story Slab Air-Source Heatpump Electricity $1,706 $1,402 $304 $4,2

2 1 Miami, FL One-story Slab Gas Furance / AC Gas $1,603 $1,303 $299 $3,9

3 2 Daytona Beach, FL One-story Slab Air-Source Heatpump Electricity $1,674 $1,404 $271 $4,

4 2 Daytona Beach, FL One-story Slab Gas Furance / AC Gas $1,589 $1,317 $273 $3,

5 3 Fort Worth, TX One-story Slab Air-Source Heatpump Electricity $1,950 $1,580 $370 $4,4

6 3 Fort Worth, TX One-story Slab Gas Furance / AC Gas $1,858 $1,499 $360 $4,1

7 4 St. Louis, MO One-story Basement Air-Source Heatpump Electricity $2,228 $1,812 $416 $4,0

8 4 St. Louis, MO One-story Basement Gas Furance / AC Gas $1,977 $1,608 $368 $3,5

9 5 Indianapolis , IN One-story Basement Air-Source Heatpump Electricity $2,276 $1,783 $493 $4,

10 5 Indianapolis , IN One-story Basement Gas Furance / AC Gas $1,972 $1,571 $401 $3,

11 6 Burlington, VT One-story Basement Air-Source Heatpump Electricity $2,763 $2,058 $705 $5,

12 6 Burlington, VT One-story Basement Gas Furance / AC Gas $2,261 $1,727 $534 $3,

13 7 Duluth, MN One-story Basement Gnd-Source Heatpump Electricity $3,365 $1,749 $1,616 $9,

14 7 Duluth, MN One-story Basement Gas Furance / AC Gas $2,547 $1,881 $666 $3,6

ENER3 Annual Utility BillsCosts

otes: Purchased energy costs were calculated assuming a national average cost of $0.11 / kWh and $1.33 / therm

averaging the data for 2008 from the Energy Information Administrations Average Retail Price of Electricity tThe natural gas rate was determined by averaging the data for 2008 from the Energy Information Administratto Residential Consumers.

Monthly mortgage cost was calculated assuming a 30-year fixed mortgage with a 5.0% interest rate.


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ajor Housing CharacteristicsOne City Miam

2,200 Climate Zone2,200 Space Heating Fuel

Slab Water Heating Fuel

cremental Costs

Measure Efficient Level (ENERGY STAR Version 3)

NERGY STAR Reference Design

(See Heating Equipment)

8.2 HSPF / 14.5 SEER / 12 EER ASHP; Electric Backu

Radiant Barrier

eiling Insulation R-30 R-30

Grade I Installation

bove-Grade Wall Insulation R-13 R-13


oundation Insulation No Slab Insulation No Slab Insulation

oundation Insulation Installation Grade I Installation Grade I Installation

6.0 ACH50

U-value: 0.60 / SHGC: 0.27

R-4.8 Door Insulation

0.92 EF Electric DHW, 52 Gallons

Programmable Thermostat

4 CFM per 100 ft of CFA

R-8 Attic, R-6 Other Uncond. Spaces

ENERGY STAR Dishwasher

ENERGY STAR Refrigerator80% ENERGY STAR CFLs

ENERGY STAR Exhaust Fans

NERGY STAR Checklists

hermal Enclosure System - Rater

VAC Sys. Quali ty Install. - Contractor

VAC Sys. Quality Instal l. - Rater

ater Managem ent System - Builder

ories

oundation Type

otal Conditioned Floor Area (ft)

eating Equipment

indows

filtration

adiant Barrier

eiling Insulation Installation

No Radiant Barrier

Elec

Elec

Grade II Installation

athroom Exhaust Fans

uct Sealing

uct Insulation

shwasher

efrigeratorghting



Programm able Thermostat

oors

G Wall Insulation Installation Grade III Installation

ater Heater

hermostat

7.0 ACH50

U-value: 0.75 / SHGC: 0.30

Exhibit 2: Sample Home 1 - Incremental Costs for ENERGY STAR Version 3 Qualified Hom

onditioned Floor Area per Floor (ft)

7.7 HSPF / 13 SEER / 11 EER ASHP; Electric Backu

(See Heating Equipment)ooling Equipment

Baseline Level (2009 IECC) U

CZ 1



50% Fluorescent Lighting

Standard Efficiency Exhaust Fans

Standard Efficiency Dishwasher

Standard Efficiency Refrigerator


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ajor Housing CharacteristicsOne City Miam

2,200 Climate Zone2,200 Space Heating Fuel

Slab Water Heating Fuel

cremental Costs



14.5 SEER Central AC

80 AFUE gas furnace

Radiant Barrier







6.0 ACH50

U-value: 0.60 / SHGC: 0.27


0.61 EF Gas DHW, 40 gallons




















80 AFUE gas furnace

13 SEER Central ACooling Equipment


CZ 1

indows

filtration

ater Heater

hermostat




oors

No Radiant Barrier



uct Sealing

uct Insulation

shwasher

efrigeratorghting

7.0 ACH50

U-value: 0.75 / SHGC: 0.30

Gas

Gas

ories

oundation Type



eating Equipment

adiant Barrier



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ajor Housing CharacteristicsOne City Day

2,200 Climate Zone CZ 22,200 Space Heating Fuel Elec

Slab Water Heating Fuel Elec

cremental Costs





Radiant Barrier







6.0 ACH50

U-value: 0.60 / SHGC: 0.27














ooling Equipment

Baseline Level (2009 IECC)

U-value: 0.65 / SHGC: 0.30

adiant Barrier


filtration 7.0 ACH50

indows

No Radiant Barrier


uct Sealing

uct Insulation

shwasher

efrigeratorghting



hermostat




oors

ater Heater





ories

oundation Type


eating Equipment

U








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ajor Housing CharacteristicsOne City Day

2,200 Climate Zone CZ 22,200 Space Heating Fuel Gas

Slab Water Heating Fuel Gas

cremental Costs




80 AFUE gas furnace

Radiant Barrier







6.0 ACH50

U-value: 0.60 / SHGC: 0.27

















ories

oundation Type


eating Equipment



U





No Radiant Barrier

oors

ater Heater



80 AFUE gas furnace

13 SEER Central AC




uct Sealing

uct Insulation

shwasher

efrigeratorghting

hermostat

ooling Equipment


U-value: 0.65 / SHGC: 0.30

adiant Barrier



indows


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ajor Housing CharacteristicsOne City Fort

2,200 Climate Zone CZ 32,200 Space Heating Fuel Elec

Slab Water Heating Fuel Elec

cremental Costs





Radiant Barrier







5.0 ACH50

U-value: 0.35 / SHGC: 0.30

















ories

oundation Type


eating Equipment



U





No Radiant Barrier

oors

ater Heater








uct Sealing

uct Insulation

shwasher

efrigeratorghting

hermostat

ooling Equipment


U-value: 0.50 / SHGC: 0.30

adiant Barrier



indows


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ajor Housing CharacteristicsOne City Fort


Slab Water Heating Fuel Gas

cremental Costs




80 AFUE gas furnace

Radiant Barrier







5.0 ACH50

U-value: 0.35 / SHGC: 0.30














ooling Equipment


U-value: 0.50 / SHGC: 0.30

adiant Barrier



indows

No Radiant Barrier


uct Sealing

uct Insulation

shwasher

efrigeratorghting



hermostat




oors

ater Heater



80 AFUE gas furnace

13 SEER Central AC

ories

oundation Type


eating Equipment

U








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ajor Housing Characteristics

One City St. L2,200 Climate Zone CZ 4

2,200 Space Heating Fuel Elec

Unconditioned Basem ent Water Heating Fuel Elec

cremental Costs





No Radiant Barrier





oundation Insulation R-19 Floor Insulation R-19 Floor Insulation

oundation Insulation Installation Grade II Installation Grade I Installation

5.0 ACH50

U-value: 0.32 / SHGC: 0.40






ENERGY STAR DishwasherENERGY STAR Refrigerator

80% ENERGY STAR CFLs







Grade III Installation

oors

eating Equipment

adiant Barrier


filtration

G Wall Insulation Installation

U

ooling Equipment



ories

oundation Type


No Radiant Barrier



uct Sealing

uct Insulation

shwasherefrigerator

indows

7.0 ACH50



ghting

ater Heater

hermostat







U-value: 0.35 / SHGC: 0.45






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ajor Housing CharacteristicsOne City St. L


Unconditioned Basem ent Water Heating Fuel Gas

cremental Costs



13 SEER Central AC

90 AFUE gas furnace

No Radiant Barrier






oundation Insulation Installation Grade II Installation Grade I Installation

5.0 ACH50

U-value: 0.32 / SHGC: 0.40















7.0 ACH50




U-value: 0.35 / SHGC: 0.45



ghting

ater Heater

hermostat




13 SEER Central AC


uct Sealing

uct Insulation

shwasher

efrigerator



50% Fluorescent LightingStandard Efficiency Refrigerator

ories

oundation Type


ooling Equipment


oors

eating Equipment

adiant Barrier


filtration


No Radiant Barrier

80 AFUE gas furnace

indows


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ajor Housing CharacteristicsOne City India

2,200 Climate Zone CZ 52,200 Space Heating Fuel

Unconditioned Basem ent Water Heating Fuel

cremental Costs




9.25 HSPF / 14.5 SEER / 12 EER ASHP; Electric Back

No Radiant Barrier






oundation Insulation Installation Grade I Installation

4.0 ACH50

U-value: 0.30 / SHGC: 0.45











VAC Sys. Quality Install. - Contractor

VAC Sys. Quali ty Instal l. - Rater


ories

oundation Type

otal Conditioned Floor Area (ft)onditioned Floor Area per Floor (ft)




U

ooling Equipment


Elec

Elec

adiant Barrier






uct Sealing

uct Insulation

shwasher

efrigerator

7.0 ACH50





indows


R-2.9 Door Insulationoors

filtration


ghting

ater Heater

hermostat



eating Equipment

No Radiant Barrier

U-value: 0.35 / SHGC: 0.45



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ajor Housing CharacteristicsOne City India



cremental Costs



13 SEER Central AC

90 AFUE gas furnace

No Radiant Barrier







4.0 ACH50

U-value: 0.30 / SHGC: 0.45
















indows

oors


No Radiant Barrier

80 AFUE gas furnace

13 SEER Central AC


U-value: 0.35 / SHGC: 0.45

7.0 ACH50


shwasher

efrigerator



ghting

ater Heater

hermostat




eating Equipment

adiant Barrier





filtration


uct Sealing

uct Insulation

ories

oundation Type



U

ooling Equipment



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ajor Housing CharacteristicsOne City Burli



cremental Costs




9.50 HSPF / 14.5 SEER / 12 EER ASHP; Electric Back

No Radiant Barrier







4.0 ACH50

U-value: 0.30 / SHGC: 0.45














Elec


No Radiant Barrier




U-value: 0.35 / SHGC: 0.45

7.0 ACH50




indows

U

ooling Equipment


ories

Elec

oundation Type

ater Heater

hermostat






uct Sealing




uct Insulation

shwasher

efrigeratorghting


oors

eating Equipment

adiant Barrier


filtration



14/26


ajor Housing CharacteristicsOne City Burli



cremental Costs



13 SEER Central AC

90 AFUE gas furnace

No Radiant Barrier







4.0 ACH50

U-value: 0.30 / SHGC: 0.45














ories

oundation Type


ooling Equipment


eating Equipment

adiant Barrier


filtration


13 SEER Central AC

uct Insulation

shwasher

efrigeratorghting

No Radiant Barrier

80 AFUE gas furnace



U-value: 0.35 / SHGC: 0.45

7.0 ACH50

hermostat






uct Sealing





indows

U

ater Heater




oors


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ajor Housing CharacteristicsOne City Dulu



cremental Costs




3.3 COP / 14.1 EER Ground-Source Heatpump

No Radiant Barrier







4.0 ACH50

U-value: 0.30 / SHGC: 0.45














ories

oundation Type





U

ooling Equipment


Elec

Elec

adiant Barrier






uct Sealing

uct Insulation

shwasher

efrigerator

7.0 ACH50





indows


R-2.9 Door Insulationoors

filtration


ghting

ater Heater

hermostat



eating Equipment

No Radiant Barrier

U-value: 0.35 / SHGC: 0.45



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ajor Housing CharacteristicsOne City Dulu



cremental Costs



13 SEER Central AC

90 AFUE gas furnace

No Radiant Barrier







4.0 ACH50

U-value: 0.30 / SHGC: 0.45
















indows

oors


No Radiant Barrier

80 AFUE gas furnace

13 SEER Central AC


U-value: 0.35 / SHGC: 0.45

7.0 ACH50


shwasher

efrigerator



ghting

ater Heater

hermostat




eating Equipment

adiant Barrier





filtration


uct Sealing

uct Insulation

ories

oundation Type



U

ooling Equipment



17/26


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ENERGY STAR Qualified Homes, Version 3Thermal Enclosure System Rater ChecklistSavings & Cost Estimate

Average Estimated Incremental Cost:

The net cost for the checklist is estimated to be $350.

Average Estimated Incremental Savings:

Energy savings of approximately 15% in heating and cooling load and consumption are estimated as a resultof the fully-aligned air barriers and air sealing measures that are required in this checklist. These measures willsave energy by reducing convective loops and conduction losses.

For the reduced thermal bridging section of the checklist, it is assumed that a reduced framing fraction of 17%will be achieved for exterior walls and 7% will be achieved for ceilings. Average combined annual heating andcooling energy savings from advanced framing techniques have been shown to vary between roughly 3% and5%.

Rationale:

Incremental costs for the Fully-Aligned Air Barrier section and Air-Sealing section of the checklist arecomprised of added material and labor costs associated with implementing the checklist. Compliance costs willvary widely depending on the percentage of requirements applicable to a particular home, the number ofrequirements not already being met through standard practice, the complexity of the home, and the strategiesused for compliance. Over the past few years of implementing the Thermal Bypass Checklist, which is similarto these two sections, EPA has received anecdotal evidence that average incremental costs for labor andmaterial are approximately $175. EPA has included an additional $50 for the new requirement to sealsheetrock to the top plate in wall assemblies.

The purpose of the Reduced Thermal Bridging section of the checklist is to reduce the impacts of thermal

bridging over standard construction methods by decreasing the level of unnecessary framing and allowingmore space for insulation to be installed. This is accomplished by requiring the builder to either adoptadvanced framing techniques based upon optimum value engineered (OVE) principles or by using anadvanced wall system such as SIP panels, Insulated Concrete Forms, or double-walls. The increased design,training, and inspection costs for the reduced thermal bridging section of the checklist will be offset by materialsavings, based upon an ACEEE study and EERE fact sheet cited in the following section. Therefore, theincremental costs were conservatively estimated at zero for this section of the checklist.

Incremental costs for meeting the High-Performance Windows and Quality-Installed Insulation sections of thechecklist were accounted for separate from this estimate.

In addition, there will be an incremental cost for third-party verification of this checklist. Third-party inspection

costs are estimated at an additional $125 per home.

The overall incremental cost for the Fully-Aligned Air Barrier section, Air-Sealing section, and ReducedThermal Bridging section of the checklist is therefore estimated to be $350.

Energy savings for the Fully-Aligned Air Barrier section and Air-Sealing section are also variable and difficult toassess. For example, the presence and impacts from convective loops, which may significantly degrade theperformance of an insulated component, are not recognized nor the impacts quantified in typical energysimulation software. One study compared the real-world energy intensity of homes in Phoenix qualified underthe original (i.e., 1995-2006) ENERGY STAR guidelines with those qualified under the Environments for Living(EFL) program. Some of the key differences in program requirements at that time were that EFL containedadditional requirements similar to the current Thermal Bypass Checklist, such as an air-barrier and insulation


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field inspection. EFL homes were shown to have approximately 15% less summer energy consumption thanthe ENERGY STAR qualified homes and is used as the basis for the above estimate.

A conservative estimate of savings for the Reduced Thermal Bridging section was determined by estimatingthe reduced framing fraction associated with the least aggressive measure (i.e., the key design techniques forOVE walls) and then modeling this reduced framing fraction in typical housing configurations. The estimationof representative framing fractions of walls and ceilings before and after the application of these techniques isillustrated in the Supporting Documentation section. The savings estimate was also compared with the resultsfrom an ACEEE study and EERE fact sheet. The proposed ENERGY STAR reduced framing fraction does notinclude all of the typical aspects of more-aggressive OVE practices (e.g. in-line framing, single top plate) andso cannot reach framing levels as low as OVE. On the other hand, some partners will utilize other optionsavailable on the checklist, such as SIPs, which will result in even lower framing fractions.

Supporting Documentation:

The reference for the study comparing EFL and ENERGY STAR qualified homes in Phoenix, mentionedabove, is as follows:

Swanson, Colby. Measuring Public Benefit from Energy Efficient Homes. Advanced Energy, Raleigh, NC.2005.

According to the 2004 ACEEE Emerging Technologies & Practicesstudy, homes with optimum valueengineering (OVE) framing can experience ~1% cooling electricity savings and ~2% heating gas savingsannually. The aggressive techniques outlined by ACEEE include 24 OC stud spacing, in-line framing, singletop plate, two-stud corners, and ladder T-walls. According to the study, material cost savings would beneutrally offset by increased design and training costs. Savings were estimated relative to a standard 2x4 16OC wall with 26.1% framing fraction.

The August 2000 Advanced Wall FramingTechnology fact sheet released by EERE claims combined annualheating and cooling savings of up to 5% with the same construction techniques suggested by ACEEE. Thefact sheet also estimated labor cost savings between 3% and 5% and material cost savings of $500 and$1,000 for 1,200 and 2,400 sqft homes, respectively. This equates to roughly $0.42 material savings per sqftof floor space.


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The following RESNET table shows framing fraction values for both standard and advanced construction.

Table 303.4.1.3. Default Framing Fractions for Enclosure Elements

DefaultFrame

Fraction(area)

FrameSpacing (in.

OC)Enclosure Element

Walls (standard):@16" OC 16 23%@24" OC 24 20%

Walls (advanced):@16" OC 16 19%@24" OC 24 16%Structural Insulated Panels (SIPs) 48 10%

Ceilings (standard trusses):@16" OC 16 14%@24" OC 24 11%

Ceilings (conventional framing):@16" OC 16 13%@24" OC 24 9%

Ceilings (advanced trusses raisedheel):

@16" OC 16 10%@24" OC 24 7%

Source: 2006 Mortgage Industry National Home Energy Rating SystemsStandards

The wall below has the same framing fraction as RESNETs default value for a standard wall with 16 OCframing.

30 2x4 16 OC Standard Wall with Two Windows (4-1 x 3-8.5) i,ii

Top & Bottom Plates: 3 *30 * 1.5 = 11.3 sqftKing Studs: 23 * 7-7.5 * 1.5 = 21.9 sqftT-Wall Intersection: 7-7.5 * 3.5 = 2.2 sqft4-Stud Corner: 4 * 7-7.5 * 1.5 = 3.8 sqftCripples & Jacks: 8 * 2-8.5 * 1.5 + 4 * 6-6.5 * 1.5 = 6.0 sqftSills: 2 * 4-1 * 1.5 = 1.0 sqftHeader: 2 * 4-4 * 11.5 = 8.3 sqftTotal Wood Area = 54.5 sqftFraming Fraction = 54.5 / (30 * 8) = 23%


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Below is a wall configuration that reflects a best-case application of the OVE techniques required by theframing checklist, which results in a framing fraction of 15%. The addition of complicated architecturalcharacteristics would add to total framing fraction. Also, effective insulations levels will likely be reduced due to

compression behind ladder t-wall framing and corner framing. It is therefore assumed that a higher framingfraction of approximately 17% will be achieved on average, which is equivalent to a 25% reduction from theRESNET standard of 23% framing fraction.

30 2x6 16 OC ENERGY STAR Wall with Two Windows (4-1 x 3-8.5) i,ii

Top & Bottom Plates: 3 *30 * 1.5 = 11.3 sqftKing Studs: 19 * 7-7.5 * 1.5 = 18.1 sqftLadder T-Wall Intersection: 3 * 16 * 3.5 = Insulated3-Stud Corner: 2 * 7-7.5 * 3.5 = InsulatedCripples & Split Trimmers: 10 * 2-8.5 * 1.5 + 4 * 3-8.5 * 1.5 = 5.2 sqftSills: 2 * 4-4 * 1.5 = 1.1 sqftHeader: 2 * 4-4 * 11.5 = InsulatedTotal Wood Area = 35.7 sqft

Framing Fraction = 35.7 / (30 * 8) = 15%


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The ceiling below has the same framing fraction as RESNETs default value for a standard ceiling with 24 OCframing.

30 x 34 24 OC Standard Ceiling i,ii

Rim Joists: 2 * 34 * 1.5 = 8.5 sqfti ii: 2 * 34 * 6 = 34.0 sqftInsulation Compression

Truss Components: 18 * 29-9 * 1.5 = 66.9 sqftAttic Hatch: 2 * 1-10.6 * 1.5 = 0.5 sqftHVAC Platform: 4 * 1-10.6 * 1.5 = 0.9 sqftTotal Wood Area = 110.8 sqftFraming Fraction = 110.8 / (30 * 34) = 11%

Below is a ceiling configuration that reflects the application of the OVE techniques required by the framingchecklist, including raised-heel trusses and a raised HVAC platform, which results in a framing fraction of 7%.This reduced framing fraction matches RESNETs default value for an advanced raised-heel truss ceiling with24 OC framing.

30 x 34 24 OC ENERGY STAR Ceiling i,ii

Truss Components: 18 * 30 * 1.5 = 67.5 sqft

Attic Hatch: 2 * 1-10.6 * 1.5 = 0.5 sqftHVAC Platform: 2 * 3-10. 5 * 1.5 = InsulatedTotal Wood Area = 68.0 sqftFraming Fraction = 68.0 / (30 * 34) = 7%

iFraming components designed in Google SketchUpiiFraming components are based on a two-story home with 2,000 sqft of conditioned floor area, approximately 1,000 sqftof attic floor space, and roughly 2,000 sqft of above-grade wall area.iiiIt is assumed that insulation compression against roof sheathing near eaves results in effective increase in framing

fraction.


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ENERGY STAR Qualified Homes, Version 3HVAC System Quality Installation Contractor ChecklistSavings & Cost Estimate




Combined energy savings for complying with the requirements for proper heating and cooling system design,equipment selection, refrigerant tests, electrical measurements, air flow tests, air balancing, and systemcontrols are estimated to be 2.5% of heating consumption for combustion appliances, 5% of heatingconsumption for air-source heatpumps, and 5% of cooling consumption for heatpumps and air conditioners. Inaddition, savings from proper duct design and installation are estimated using a reduction in duct leakage from4.0 to 3.4 CFM per 100 square feet of conditioned floor area (representing a 15% improvement).

Energy savings are not anticipated as a result of implementing the ventilation and filtration requirementsrelated to ASHRAE 62.2-2010. Additional energy used to provide the required ventilation is recognized byRESNET-accredited Home Energy Rating software programs and reflected in the resulting HERS index value.

Rationale:

It is estimated that increased design efforts, required for compliance with ACCA Manual J, S, & D, and for theventilation design, will cost approximately $0.35 per square foot or approximately $750 for an average sizedhome. However, the increased cost for proper design is assumed to be partially offset with $500 in savingsfrom a one ton reduction in equipment size. The cost for equipment commissioning is approximately $125. Anadditional $25 cost for jump ducts or transfer grilles is also assumed.

Ventilation strategies and associated costs will vary between homes. For this estimate, the cost of an air-cycler with motorized damper was included at a cost of $125 with an additional $100 for installation. Exhaust-only strategies may be less expensive and systems with integrated energy management will be more

expensive.

EPA does not anticipate an increase in cost to meet the requirement for mechanically drafted or direct-ventedspace heating combustion equipment. A review of furnaces certified by the Gas Appliance ManufacturersAssociation indicates that over 90% of products with an efficiency of 78-80% AFUE meet this requirement. Inthe case of high-efficiency direct-vented equipment, the costs may actually decrease due to reducedinstallation costs that result from the elimination of the B-vent. An incremental cost of $125 is estimated for therequirement for mechanically drafted or direct-vented water heating equipment, which is typically higher inefficiency than atmospherically vented equipment.

Miscellaneous costs for items such as garage door gasketing, sealing of ducts boots to drywall, and acompliant HVAC filter are estimated at $50.

The cost of an ECM evaporator motor has been incorporated as a partial cost, as it is not a requirement, but isprevalent in high efficiency air conditioning equipment. The partial cost for the ECM evaporator motor isestimated to be $75.

Energy savings are based upon an ACEEE paper, Ecotope paper, and Energy Center of Wisconsin paper,cited below, that estimated the typical energy savings for proper sizing and commissioning of HVACinstallations in new construction.



24/26

ENERGY STAR Qualified Homes, Version 3HVAC System Quality Installation Contractor ChecklistSavings & Cost Estimate

CL&P and UI Program Savings Documentation for 2008 Program Year states that the average minimum costfor the diagnostics step of heat pump or central AC commissioning is $125, though additional labor costs mayapply depending on location, contractor, or any issues that may arise with refrigerant charge adjustment.

Design costs of $0.35 per square foot of floor area are based upon an email exchange with Dennis Stroer,CalcsPlus, who provides a similar service. The cost savings for a one ton reduction in AC size is estimatedusing an average equipment cost per ton of approximately $500 based upon a Navigant Consulting documentprepared for the Energy Information Administration entitled, Technology Forecast Updates - Residential andCommercial Building Technologies - Reference Case Second Edition (Revised).

According to the 1999 ACEEE study Energy Savings Potential from Addressing Residential Air Conditionerand Heat Pump Installation Problems, the following are major contributors to potential HVAC and distributionsystem energy savings:

Characteristic Energy Savings PotentialEquipment Sizing 2-10%

Airflow over Indoor Coil 7%Refrigerant Charge 13%Duct Leakage 10-15%

Due to interactive effects between equipment sizing, airflow, refrigerant charge, and duct leakage, however,individual energy savings are not directly additive. The ACEEE study suggests that typical energy savings forproper sizing, commissioning, and duct installation can result in average energy savings of about 35% for newconstruction installations. By subtracting the full duct leakage component from this estimate, a final savingsvalue of about 19-20% is achieved.

In contrast to ACEEE, a 2008 paper authored by Scott Pigg of the Energy Center of Wisconsin, entitledCentral Air Conditioning in Wisconsin: A compilation of recent field research, found more conservativesavings on the order of 5%. The paper notes that the more conservative estimate blends many systems thathave little or no potential for efficiency improvement from tune-up with a few systems where large savings canbe achieved by correcting undercharged systems and reducing airflow.

For its analysis, EPA assumed a conservative national average estimate of 5% cooling energy savings for allhomes and 5% heating energy savings for homes with heatpumps. It assumed a more conservative nationalaverage estimate of 2.5% heating energy savings for homes with gas heating. In addition, savings for properduct design, installation, and pressure-balancing were accounted for by assuming a 15% reduction in effectiveduct leakage from 4.0 to 3.4 CFM per 100 square foot of conditioned floor area.

Regarding ventilation requirements, the cost of an air-cycler system with motorized damper was referencedfrom Eco-Smarts online store: http://www.ecosmartinc.com/catac9special.php

The estimate of a $125 incremental cost for non-atmospherically vented water heaters was estimated asfollows. First, an estimate of $250 was derived using the approximate average installed differential costbetween equipment with 0.61 EF and 0.64 EF (presumed to be non-atmospherically vented), as reported byNavigant Consulting. EIA - Technology Forecast Updates - Residential and Commercial Building Technologies- Reference Case Second Edition (Revised). Reference number 20070831.1. 2007. Second, this number wasreduced by 50% as a gross estimate of the percentage of homes that will not need to comply with thisrequirement, including those with electric water heaters or with gas water heaters installed outside thepressure boundary.

2006 RS Means was used to estimate an hourly labor rate. An hourly rate of $46 for a skilled worker foremanincluding overhead and profit, was assumed.
http://www.ecosmartinc.com/catac9special.phphttp://www.ecosmartinc.com/catac9special.phphttp://www.ecosmartinc.com/catac9special.php


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ENERGY STAR Qualified Homes, Version 3HVAC System Quality Installation Rater ChecklistSavings & Cost Estimate




Savings associated with this checklist are captured within the savings estimate for the HVAC System QualityInstallation Contractor checklist.

Rationale:

The main components of this checklist are the collection and simplified review of the completed HVAC SystemQuality Installation Contractor checklist; measurement of the duct system for leakage; visual inspection of theduct system for pressure-balancing features and major defects in duct design and installation; andmeasurement and visual inspection of the ventilation and exhaust systems. It is expected that this can be

completed within two and a half hours of onsite inspection and an additional hour and a half of off-sitecoordination with the HVAC contractor.


2006 RS Means was used to estimate an hourly labor rate. An hourly rate of $46 for a skilled worker foremanincluding overhead and profit, was assumed.


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ENERGY STAR Qualified Homes, Version 3Water Management System Builder ChecklistSavings & Cost Estimate


The net cost for the Water Management System Builder checklist is estimated to be $100.


Energy savings are not anticipated as a result of implementing the Water Managed checklist.

Rationale:

The requirements contained within the Water Management System Builder checklist are largely required bycode. Therefore, the significant costs result from additional training, improved practices, and third-partyinspection. Additional training and improved practices, which may require additional time, are expected to addapproximately $100 per home.

Energy Star Homes - Estimated Cost and Savings

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