Residential Energy Evaluation Manual

8/3/2019 Residential Energy Evaluation Manual

1/62

NEW Military Family Housing

R esidentialEnergy

Evaluation

Manual

U n i t e d S t a t e s Air F o r c e

Mounta in Home AFB, Idaho


2/62

Disclaimer

This Manual was prepared by Delta Research Corporation under contract by the UnitedStates Government. Neither the United States, nor the United States Department ofDefense, nor any of their employees, contractors, or subcontractors makes any warranty,expressed or implied, or assumes any legal liability or responsibility for the accuracy,completeness, or usefulness of any information, apparatus, product, or processdisclosed.

The residential energy design guidelines presented in this Manual are recommendationsonly, and do not supersede any applicable energy conservation building coderequirements. The reader is responsible for determining the applicable coderequirements, and proposing a design in compliance with these code requirements.


3/62

Preface

The United States Air Force is committed to improving Military Family Housing. Thiscommitment is being vigorously executed through a balanced approach of renovation ofexisting structures and new housing construction. As an important consideration inhousing design and construction, energy efficiency has become a key element in theevaluation of each contractors proposal. The Air Force remains dedicated to improvingenergy efficiency in family housing, and supports the use of leading energy technologyand renewable forms of energy when consistent with reliability, cost, and other designcriteria.

The Residential Energy Evaluation Manual (REEM) is a key part of the Air Force housingprocurement process, and is designed to serve several functions. First, the Manualprovides the contractor energy budgets for each type of housing identified in the Requestfor Proposal (RFP) for new construction. Second, the Manual provides a simple

procedure for evaluating the energy effectiveness of any proposed design. Theevaluation procedure is standardized for each model type, thereby providing a commonmethod to evaluate individual proposals. If the proposed design exceeds the energybudget allowed in the REEM, the contractor must alter his design to meet or exceed theenergy budget standard. Designs not meeting energy budget standards will bedisqualified from contract award. The REEM also provides information on energy saving

techniques which may aid the contractor in meeting energy budget requirements.

The Manual offers a straightforward energy computational process that is easy for thecontractor to use. The REEM uses design criteria and energy calculation procedures ina stepwise manner to guide the designer to the optimal residential energy designsolution. The calculation process provided in this Manual is simple, and requires onlyminimal computations. The calculation process is based on state-of-the-art buildingenergy analysis simulations and monitored building energy performance data. Theprocedures provided in this Manual are applicable to a wide range of energy-efficientresidences including conventional, sun-tempered, passive solar, or super-insulated.

This Manual is divided into four chapters. Each chapter provides a step-by-step processleading to the completion of the energy assessment required by the RFP. Chapter Oneprovides an overview of the use of the REEM, and should be read before proceeding toany of the other chapters.

i


4/62

TABLE OF CONTENTS

Page

List of Tables and Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .iii

Chapter One: How to Use the Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Chapter Two: The Energy Budget . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7

2.2 The Energy Budget . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

2.3 Life Cycle Energy Costs . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Chapter Three: Energy Conservation Measures. . . . . . . . . . . . . . . . . . . . . . 3-1

3.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3.2 Climate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13.3 Conventional Design Considerations . . . . . . . . . . . . . . . 3-2

3.3.1 The Building Envelope . . . . . . . . . . . . . . . . 3-43.3.2 Mechanical Equipment . . . . . . . . . . . . . . . 3-113.3.3 Domestic Hot Water . . . . . . . . . . . . . . . . . 3-12

3.4 Solar Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-133.4.1 Passive Solar Considerations . . . . . . . . . . 3-133.4.2 Site Planning . . . . . . . . . . . . . . . . . . . . . . 3-14

3.4.3 Interior Design . . . . . . . . . . . . . . . . . . . . . 3-16

Chapter Four: Energy Calculation Procedures . . . . . . . . . . . . . . . . . . . . . . 4-1

4.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-14.2 Definition of Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

4.3 Structure of Point System . . . . . . . . . . . . . . . . . . . . . . . 4-2

4.4 Interpolating Between Energy Conservation Measures . . 4-34.5 Compliance with the Energy Budget . . . . . . . . . . . . . . . 4-3

4.6 Point System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

4.7 Point System Instructions . . . . . . . . . . . . . . . . . . . . . . . 4-4

4.8 Point System Example . . . . . . . . . . . . . . . . . . . . . . . . . 4-6

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . R-1

Appendix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

ii


5/62

LIST OF TABLES AND FIGURES

Tables Page

Table 2.1:

Table 2.2:

Table 3.1:

Table 3.2:

Table 3.3:

Table 3.4:

Table 4.1: Window Shading Coefficients . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Figures

Figure 1.1 : Manual Procedure Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Figure 2.1:

Figure 3.1: Idaho Climate Zones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1Figure 3.2: Building Envelope Considerations . . . . . . . . . . . . . . . . . . . . . 3-4

Figure 3.3: Slab Floor Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Figure 3.4: R-19 Standard Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

Figure 3.5: R-19 Equivalent Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

Figure 3.6: R-21 Standard Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

Figure 3.7: R-30 Standard Ceiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8

Figure 3.8: R-38 Standard Ceiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8

Figure 3.9: Summer and Winter Sun Angles for Southern Idaho . . . . . . . 3-14

Figure 3.10: Solar Gain in Summer and Winter in Southern Idaho . . . . . . 3-15

Figure 3.11: Examples of Thermal Mass . . . . . . . . . . . . . . . . . . . . . . . . . 3-16

Heating and Cooling Budgets for Single-FamilyRanch Style Houses and Two-Story Duplex Houses . . . . . . . . 2-2Life Cycle Energy Cost in Dollars forTwo Prototype Houses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Thickness in Inches of Select Insulationand Corresponding R-Values . . . . . . . . . . . . . . . . . . . . . . . . . 3-5Thickness in Inches of Select Rigid Insulationand Corresponding R-Values . . . . . . . . . . . . . . . . . . . . . . . . . 3-6R-Value and Cost Index for Select Door Construction . . . . . . . 3-9

Infiltration Reduction Measures . . . . . . . . . . . . . . . . . . . . . . . 3-9

Projected Energy Consumptionby Major Category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4


6/62

Residential Energy Evaluation Manual (REEM)

Mountain Home Air Force Base

Chapter One

How to Use the Manual

This Manual is part of a larger Air Force housing procurement package. Therefore, it maybe necessary to move back and forth between this Manual and other sections of the RFP.In order to help you facilitate the preparation of information called for by the RFP, referto Figure 1.1 and the step-by-step procedures described on the pages following.


7/62



STEP ONE: Review RFP and REEM

Your proposed design solution must satisfy the requirements described in both the RFPand this Manual. Design guidelines are presented in Chapter Three to assist you inachieving the desired level of energy performance. Individual energy-saving techniquesare presented that are realistic and cost effective. It is up to the designer to choose theappropriate energy conservation measures that best fit the individual designs.

STEP TWO: Identify Mandatory Energy Requirements

Your proposed design solution must satisfy the energy budget requirements as defined

in Chapter Two. Any design that exceeds the required energy budget will be disqualifiedfrom contract consideration. Designs that are projected to be below the required energybudget will receive additional consideration in the proposal evaluation process. Youshould choose the combination of energy-saving techniques that are most compatible toyour design approach and cost goals. Cost effectiveness should be a majorconsideration when choosing the mix of energy-saving features to achieve the energybudget.

STEP THREE: Design Prototypes

With the energy budget defined in Chapter Two and the energy conservation measuresdescribed in Chapter Three in mind, you should now develop a conceptual energy designpackage that complies with the overall housing design criteria contained in the RFP.

STEP FOUR: Complete Point System Worksheets

Once a conceptual design for each unit type has been developed, you should completethe point system forms contained in Chapter Four. These forms must be completed foreach unit type. Instructions for preparing these point system forms is described inSection 4.2, Definition of Points.

YOU SHOULD MAKE COPIES OF THE FORMS PRIOR TO FILLING THEM OUTAND KEEP THE MANUAL COPIES AS MASTERS.

1-2


8/62



STEP FIVE: Compare Energy Performance Against Energy Budgets

The energy performance of each unit/building type should be compared to the energybudget for that unit type. If your design satisfies the energy budget, then proceed toStep Six. If your design does not satisfy the energy budget, identify what elements of theunit design are causing poor performance, adjust those elements and return to Step Fouras shown in Figure 1.1.

STEP SIX: Complete Documentation and Submit Proposal

When you are satisfied with the energy performance of each unit and the total project,

complete all the required documentation and submit the final package for Air Forcereview.

1-3


9/62



Chapter Two

The Energy Budget

2.1 Overview

This chapter provides information about the heating and cooling energy budget andprojected life cycle costs for the residential housing types identified in the RFP. Thesetwo energy products were developed to serve several functions. First, the Air Forceremains dedicated to incorporating modern, energy-saving features in new and renovatedMilitary Family Housing. As a key part of the REEM process, the energy budgettechnique is viewed as an effective way to encourage contractors to design and buildmore energy-efficient family housing. The life cycle cost summary of prototype housingis provided to assist contractors and the Air Force in developing a perspective of theeffectiveness of select energy conservation measures (ECMs).

As a member of the greater southwest Idaho community, Mountain Home Air Force Basehas elected to incorporate in this RFP energy conservation standards consistent withregional power and gas company recommendations, as well as generalrecommendations from the Idaho Energy Conservation Bureau. Information from all ofthese sources were combined to form the basis for Section 2.2, The Energy Budget.

The computation of the heating and cooling budgets and life cycle cost data is performedusing Department of Energy (DOE) developed computer programs termed COSTSAFR(Conservation Optimization Standard for Savings in Federal Residences) and CAPS(Computer Automated Point System). These two programs were developed for use byfederal agencies in the procurement of residential housing. Both programs are usedtogether, and provide projected annual energy consumption levels as well as life cycleenergy costs. The models take into consideration a variety of site-specific factorsincluding geographical location, climatology, and area cost as well as the ECMs beingconsidered for each housing type identified in the RFP. The COSTSAFR model alsoprovides a standardized, manual process to be used by contractors and the Air Forcein evaluating each prototype dwelling.

The energy budget represents a maximum energy use figure for each prototype that mustnot be exceeded by the contractor. The contractor is encouraged to use any mix of

energy-saving features consistent with the energy budget and general design

2-1


10/62



requirements. Use of the energy budget figure is intended to give the contractor flexibilityin the planning process and encourage innovation in designing energy-efficient housing.

The Heating and Cooling Energy Calculation Worksheets in Chapter Four should be usedto compare proposed housing designs with the heating energy budget. Theseworksheets must be submitted as part of the contractors proposal. In some cases, if theunit or building type varies significantly in orientation, insulation level, glazing area, orother significant specification, several heating and cooling energy calculation worksheetsmay be required for the same unit or building type. Please refer to Chapter Four formore information on energy calculation procedures.

2.2 The Energy Budget

Single-Family Ranch Two-StoryStyle Houses Duplex Houses

FOUNDATION TYPE

HVAC TYPE

Energy Conservation Measures (ECMs)

l Ceiling Insulation

l Wall Insulation

l Floor Insulation

l Infiltration

l Window Type

l Heating Equipment Ratings

l Cooling Equipment Ratings

HEATING BUDGET (KBtu/Ft2/Yr)

COOLING BUDGET (KBtu/Ft2/Yr)

Slab on Grade

Gas/Elec. Air

R-30

R-19

R-10 for 2 Ft

Average

Low E & TB

90% AFUE

10.0 SEER

43.4

2.9

Slab on Grade

Gas/Elec. Air

R-30R-19

R-10 for 2 Ft

Average

Low E & TB

90% AFUE

10.0 SEER

38.0

3.2

In Tables 2.1, a separate heating and cooling energy budget is shown for each proposedbuilding type. The tables include ECMs that meet or exceed regional and state residentialconstruction recommendations and the COSTSAFR-recommended program for newfederal residential buildings. The ECMs represent a sample set of features that will resultin compliance with the respective heating and cooling budgets. The energy budgets arespecified in thousands of Btus per square foot of conditioned space per year, and arethe projected maximum allowable energy consumption totals for each specified building

type.

Table 2.1: Heating and Cooling Budgets for Single-FamilyRanch Style Houses and Two-Story Duplex Houses

In Table 2.1, a prototype Single-Family Ranch Style House with a slab foundation, gasheat and electric air conditioning, and ECMs as shown, is projected to require 43.4KBtu/Ft

2 /Yr for heating and 2.9 KBtu/Ft

2 /Yr for cooling. Similarly, a Two-Story Duplex

2-2


11/62



House is projected to require 38.0 KBtu/Ft2/Yr for heating and 3.2 KBtu/F

2 /Yr for cooling.

The energy budgets for heating and cooling are based on a projected 68 degree internal

temperature in winter, and a 78F temperature in summer. The minimum outdoor designtemperature is 8F, and the maximum outdoor design temperature is 97F.

2.3 Life Cycle Energy Costs

The life cycle energy costs provided in Table 2.2, below, are based on outputs from theCOSTSAFR and CAPS computer models. The House Size column includes the threedifferent size units (in net square feet) and number of bedrooms required by the RFP.These three sizes correspond to Air Force size requirements for two, three, and fourbedroom Junior Noncommissioned Officer Quarters (JNCOQ). The life cycle cost figures

represent the discounted cost in current year dollars in running the heating and coolingequipment and the hot water heater of the proposed unit design for 25 years at local fuelprices and projected fuel escalation rates. The discount rate used is 7 percent. The lifecycle cost figures were developed based on the same ECMs used in Table 2.1.

Type

Single-Family RanchStyle Houses

House Size

Const. HVAC 950 Ft2

1200 Ft2

1350 Ft2

2 BR 3 BR 4 BR

Slab Gas/Elec. Air 4,296 5,492 6,207

Two-StoryDuplex Houses

Slab Gas/Elec. Air 4,101 5,259 5,945

Table 2.2 Life Cycle Energy Cost In Dollars for Two Prototype Houses

For the houses listed in the previous tables, the window area is estimated at 12 percent.The summer and winter shading coefficients are 0.4 and 0.8, respectively.

There are several aspects of Table 2.2 that merit additional comment. Upon initial review,the life cycle costs for the three prototypes may appear to be unusually low. However,the figures shown are in current year dollars. The use of then year dollars wouldpresent a much higher figure. Although Mountain Home AFB has a relatively high winterheating requirement, total energy requirements are moderated by summer temperaturesthat are generally cooler than many other areas of the country. The size of the housesis another factor that supports lower levels of energy consumption. The prototypes alsobenefit from substantial energy-saving measures and significantly lower government gas

2-3


12/62



and power rates than found nationwide. All of these factors combine to producesignificant reductions in energy expenditures.

Also, the life cycle costs shown in Table 2.2 take into account only part of the total houseenergy requirement. For example, in residential buildings outlined in Table 2.1, spaceheating and cooling account for an average of about 44 percent of total energy demand;this figure would generally be less in more moderate climates. Domestic hot water lagsbehind at 20 percent for all of the prototypes considered in this project. The remaining36 percent of projected energy consumption is divided as shown in Figure 2.1, below.

Figure 2.1: Projected Energy Consumption by Major Category

2-4


13/62



Chapter Three

Energy Conservation Measures

3.1 Overview

This chapter addresses three major areas: climate, conventional design considerations,and solar applications. The purpose of this chapter is to provide contractors information

about energy-saving techniques that are realistic, easy to install, and cost effective. Theinformation provided focuses on proven energy applications designed specifically to meetor exceed the energy budgets established in Chapter Two.

3.2 Climate

The residents of Idaho live in arelatively broad range of climates.Since climate plays a large role inresidential energy consumption, the

Idaho Energy Division establishedthree climatic zones representingthe different weather regimes withinIdaho. Mountain Home AFB islocated at the edge of ClimaticZone 1 shown in Figure 3.1. Moredetailed climatic zone boundarydescriptions and lists of locationswithin each zone are availablethrough the Idaho Department ofW a t e r R e s o u r c e s E n e r g yConservation Bureau, telephone(208) 327-7976. Figure 3.1: Idaho Climate Zones

More specifically, Mountain Home AFB is located in southwest Idaho at a surfaceelevation of 2,996 feet above mean sea level. During a typical year at Mountain HomeAFB, temperatures reach an average annual high of 63F and an average annual low of39F. Mountain Home AFB experiences four distinct seasons of about equal length: thewarm, dry, months of summer (June through August); the dry months of fall (September

3-1


14/62



through November); the cold and relatively moist winter months (December through

February); and the spring transitional period (March through May). The spring transitionmarks the end of the cloudy, cool days of winter and the start of the summer. In thespring transition, March temperatures increase from an average maximum of 52F andan average minimum of 30F to an average maximum and minimum of 71F and 44F,respectively, in May.

Summer weather is characterized by warm, dry conditions and occasional thunderstorms.Maximum temperatures average between 80F and 92F with minimum temperatures inthe mid-40s to upper-50s.

By the end of November, Mountain Home experiences a transition toward winter. Frontal

passages become more intense resulting in stronger winds and more abrupt weatherchanges. Since the mean storm tracks pass near the base during winter and farthernorth and east during summer, lower ceilings and visibilities can be expected toaccompany winter fronts. Prevailing surface wind flow transitions from light north westerlyflow in the summer, and by November, east-southeasterly flow predominates. Falltemperatures decrease from an average daily maximum and minimum of 78F and 48F,respectively, in September to an average maximum of 49F and minimum of 30F inNovember.

Winter is characterized by cloudy, cool weather with occasional periods of rain. Frontalpassages occur frequently in winter with passages expected every three to four days.

Winter maximum temperatures average in the upper-30s to low-40s with averageminimums in the low- to mid-20s.

Mountain Home AFB has an annual average of 5,570 heating degree days and 828cooling degree days.

3.3 Conventional Design Considerations

This section provides contractors with information about energy-saving considerationsthat are conventional in approach. For the purpose of this Manual, the term

conventional refers to proven, cost effective, off-the-shelf materials and hardware thatwill produce significant energy savings. A second, and equally important consideration,is that the ECMs chosen provide occupant comfort without demanding a change inlifestyle. The examples provided in the two paragraphs following highlight successfuldesign efforts that produced dramatic reductions in residential energy use. Moreover, thedesigns benefitted from a conventional approach that ensured reliability, effectiveness,and user satisfaction.

3-2


15/62



Two homebuilders in the Greater Chicago, Illinois area have an interesting incentive for

prospective home buyers: Buy from us, and we guarantee that your heating bill wontexceed $200 per year. If it does, we// pay the difference. The builders confidenceseems well placed in noting that in eight years of active homebuilding, only one has paidout any money - just $390. The homes are in the 2,500 square foot range, and a$175,000 version sells for about $3,000 (two percent) more than conventional modelsoffered by competitors.

In Tampa, Florida, a builders 2,200 square foot house scored a 16.9 out of 100 onFloridas Energy Performance Index (EPI). The EPI provides an overall rating of ECMsincorporated into a residence, with lower values indicating better performance. Homesof comparable size with normal energy-saving treatments typically score between 80 and

90. In Pensacola, Florida, another builder is projecting an 18.9 EPI on a new model, andexpects the cost to be within five to seven percent of conventionally built homes. In the

Pensacola area, where heating and cooling costs for comparable homes average $79 permonth, the builder is projecting $7.75 for monthly cooling and $3.78 for heating.

In the cases presented above, the builders used mostly conventional building techniquesemphasizing off-the-shelf products. The walls were constructed using 2 by 6 inchframing. Wall insulation was high density fiberglass batts with a super efficient R-21rating. Also, extra insulation was installed under the exterior siding. Ceiling insulationranged from R-30 to R-48. Thermal break doors, low-E (low-emissivity glass) windows(R-8), and 93 percent efficient gas furnaces were used. In smaller units (less than 2,200

square feet), no furnace was used. Instead, a system of metal coils similar to a carradiator was installed at the starting point of the forced air heating system. Hot water waspiped from the hot water heater to the coils with air being forced over the coils to heatthe house. Key leakage points were sealed with the intent to eliminate any significantuncontrolled air movement. Foam sealers were installed around plate lines, mud sills,electrical and plumbing penetrations, baseboard and band joints, and any other pointspenetrating the building envelope. The homes also benefitted from contractor educationand emphasis on proper installation of each system. Without such involvement, improperinstallation techniques can dramatically reduce the maximum performance of eachcomponent, and the system as a whole.

The key to success in the homes identified centers on a number of important factors.

l Use off-the-shelf componentsl Build a tight envelopel Use 2 by 6 inch framing with R-21 insulation and exterior sheathingl Install double pane, insulated, low-E glass and insulated doorsl Start ceiling insulation R-values at R-30l Use R-30 insulation in raised floor construction

3-3


16/62



l Install gas furnaces with 90 percent or greater AFUEl

Use air conditioning units with a SEER of 11 or higherl Take the time to seal every penetration to the building envelopel Make sure the installers know proper insulation installation techniques

3.3.1 The Building Envelope

The building envelope is basically the barrier that separates the outside environment fromthe inside environment. The building envelope refers to the outer perimeter of thestructure and generally includes the foundation, floor, walls, windows, doors, ceiling, androof. The real objective of residential energy conservation is to minimize heat flow and

infiltration through the building envelope. Figure 3.2 shows factors to consider indesigning and constructing the building envelope.

Figure 3.2: Building Envelope Considerations

Residential design considerations should emphasize a tight building envelope thatminimizes infiltration or exfiltration and heat transfer. Other envelope considerationsinclude vapor and weather barriers and adequate drainage and ventilation to compensatefor moisture deposits. Enhancements to the envelope primarily deal with the following.

3-4


17/62



l Levels and quality of insulation materials used throughout the structure.l The amount of infiltration into or out of the building.l The thermal mass of the building (materials that slow temperature changes inside

the building such as masonry and concrete).l The size, type, and shading of glass and other fenestration products.l Site considerations that better use the effects of shading and insulation.

The remainder of this section will take a closer look at the two principal factors impactingheat flow through the envelope: insulation and infiltration. The topics of thermal massand site considerations are included in Section 3.4, Solar Applications.

Insulation

Minimum net insulation requirements for the homes identified in the RFP are containedin Chapter Two, Table 2.1. Insulation materials must comply with applicable standardsregarding performance, quality, health, and safety. In most residential construction, fourtypes of insulation are installed: batts, blankets, loose fill, and rigid board. Each type hasspecific attributes and applications, but all are intended to increase a homes resistanceto heat transfer, and thereby lower energy requirements for heating and cooling.Selection of specific types of insulation should be based on R-Value ratings, as well asapplication. R-Values for select types of insulation are shown in Tables 3.1 and 3.2.

Table 3.1: Thickness in Inches of Select Insulation and Corresponding R-Values

3-5


18/62



Type R-Value for

One inch

Polystyrene

l Expanded

l Extruded

Polyisocyanurate and

Polyurethane

Phenolic

4

5

6-7

8

Table 3.2: Thickness in Inches of SelectRigid insulation and Corresponding R-Values

Slab Foundation. For slab floors, insulationis primarily intended to lessen heat transferthrough the edge of the slab. Rigid insulationis normally used around the edge of slabfoundations due to its strength and ease ofinstallation, and is applied using a masticadhesive. The perimeter insulation must alsobe protected from ultraviolet light exposureand physical damage. On polyisocyanurateor spray urethane, a protective coating should

be installed that is durable and strongenough to avoid puncture from backfill. Theslab edge insulation must have a resistanceto water absorption (.3 percent) and a vaportransmission rate of no more than 2.0perm/inch. The energy budget for MountainHome AFB requires a minimum slab Figure 3.3 Slab Floor Construction

insulation value of R-10 for two feet ordownward to the bottom of the slab. See Figure 3.3 for standard slab floor construction.

Walls. Framed walls must meet or exceed the net R-19 requirements in the energy

budget. The R-19 requirements are generally met using 2 by 6 inch wood framed wallson 16 inch centers. The insulation (R-19 with a vapor barrier next to finished inside walls)used in walls to prevent the leakage of heat is equivalent to approximately 14 inches ofsolid pine, 58 layers of inch paneling, or 90 inches of common brick. When usingconventional fiberglass batts in 2 by 6 inch walls, some compression occurs reducing theinsulation R-Values from 19.0 to 17.8. However, the net wall R-Value is increased byexterior sheathing, interior gypsum board, and interior air film to a nominal value of R-19.R-21 batts are presently available that fit into a 2 by 6 inch wall cavity (5.5 inches) without

3-6


19/62



compression. When coupled with 1 inch polystyrene sheathing, an R-Value of 26 is

produced. R-19 walls are also attained using 2 by 4 inch framing on 16 inch centers withR-13 batts and R-4.61 insulated sheathing. Assemblies for likely wall combinations areprovided in Figures 3.4, 3.5, and 3.6.

Figure 3.4: R-19 Figure 3.5: R-19Standard Wall Equivalent Wall

Figure 3.6: R-21Standard Wall

Ceilings. Ceilings, or roofs separating conditioned from unconditioned spaces, must beinsulated to a net value of at least R-30. The thermal R-Value of ceiling insulation of R-30

and R-38 is equivalent to approximately 16 layers of ceiling tile, 30 inches of solid wood,or 84 layers of gypsum board.

Ceiling insulation is achieved through a variety of insulation types which usually includebatt, blanket, loose fill, and rigid insulation. Batt and blanket insulation should be installedbetween joists or trusses and extend the full depth of the joists or trusses. If a higher R-Value is desired, the batts or blankets should be placed across or staggered above theunderlying insulation. Loose insulation is usually blown into an attic and generally has theadvantage in ease of application over batt insulation. Rigid insulation offers a relative

advantage in having higher R-Values per inch of depth and structural integrity. Rigidinsulation is useful in providing insulation for attic access doors and as a baffle around

the attic perimeter when using blown-in insulation.

Ceiling insulation should extend far enough to cover the top plate of the exterior walls.However, care should be taken to ensure that air flow from eave vents is not blocked.Blockage of eave vents could result in moisture buildup in the attic on the underside ofthe ceiling insulation. Moisture in the ceiling could result in structural damage, as well ascompression and loss of effectiveness of the insulation. Assemblies for ceilings withinsulation values of R-30 and R-38 are shown in Figures 3.7 and 3.8.

3-7


20/62



Figure 3.7: R-30 Figure 3.8: R-38Standard Ceiling Standard Ceiling

Doors and Windows. Emphasis on energy efficiency for doors and windows (glazing)began in the energy crises of the 1970s. As with other assemblies, heat flow throughwindows and doors is expressed in terms of U-Value, or the reciprocal R-Value. A higherR-Value or lower U-Value indicates better thermal insulation capabilities. Single panewindows have R-Values of approximately .9 (U-Value of 1.12). Double pane windows

improve R-Values to about 2.0. Triple glazing, or gas-filled double pane windows,generate R-Values of about 4.0. Low-E, or low-emissivity glass, is effective in reducingenergy losses due to radiant heat transfer which comprises one-half to two-thirds of totalwindow energy loss. Low-E glass, combined with several innovations such as doubleglazing, argon gas, and improved spacing, produces a one-inch thick window with an R-Value of 8. While this figure is still substantially below wall R-Values, a new double panewindow filled with tiny glass beads and using existing low-E features has been developedand is reported to give an R-Value of 16.

Minimum standards for Mountain Home AFB require windows to be low-E, argon-filledwith insulated aluminum or vinyl clad wood frames. The allowable infiltration rate for

manufactured doors is .37 cfm/sf of door area; for windows, the maximum rate is .37cfm/ft of operable sash crack. The total window area expected is 12 percent with amaximum allowance of 17 percent. Windows facing east and west should be limited to2.0 to 3.0 percent of the total floor area to minimize excessive summer solar heating. Inorder to meet the energy budget, the maximum U-Value allowed for windows is .65.Window areas in doors must be counted as part of the total fenestration or window area.Windows must also be certified by manufacturers regarding specific infiltration and

3-8


21/62



exfiltration ratings. R-Values and cost factors for select door types are presented in Table3.3.

Door cost

Construction R-Value Index

Hollow Core Wood 1.0 1.0Hollow Core Wood with Storm Door 1.5 1.9Solid Wood 2.3 1.2Solid Wood with Storm Door 3.5 2.1Metal-polystyrene Core 7.5 1.3Metal-urethane Core 13.5 1.5

Table 3.3: R-Value and Cost index for Select Door Construction

Infiltration

Heat loss in the typical home due to infiltration is estimated to account for about 30 to 40percent of a homes total heating and cooling requirement. Properly installed airinfiltration measures will significantly reduce energy consumption and minimize moisturebuildup in insulation areas of the building envelope. Table 3.4 shows several infiltrationreduction measures and their relation to the infiltration level.

InfiltrationLevel

Average

(15 Points or Less)

Tight

(15 - 35 Points)

Very Tight(Over 35 Points)

Air Changes Infiltration ReductionPer Hour Measures

.8 - 1.0 Standard Infiltration Measures(Caulk and Seal All Envelope Openings)

Average Infiltration Level Practices Plus:

l Exterior air infiltration barrier.6 - .79 l Continuous vapor retarder sheet

l Infiltration barrier and vapor retarder combined

l Foam sealed outlets and switches

l Windows and doors with certified infiltration ratesl No or insulated ceiling recessed light fixtures

.35 - .49 l All duct work located within conditioned space

l Sealed and taped duct work

l Non-cornbusting heating equipment

l Storm doors

Minimum Required .35 ASHRAE Recommended Standard

Table 3.4: Infiltration Reduction Measures

3-9


22/62



The term points in the infiltration level column relate to values assigned to specific

infiltration reduction measures used to evaluate prototype housing submitted by thecontractor. More information about the measurement of infiltration levels is included inChapter Four.

Should validation of the infiltration reduction measures be required by field testing,procedures outlined in the American Society for Testing and Materials (ASTM) publicationE 779-87, Standard Test Method for Determining Air Leakage Rate by Fan Pressurization,will serve as the standard. ASTM E 779-87 describes a standardized procedure formeasuring air-leakage rates through a building envelope under controlled pressurizationand de-pressurization. In general, a fan or blower is attached to the building envelopeusing a door, window or other suitable opening. The fan is turned on, and a range of

induced pressure differentials are established between the inside and outside of thedwelling. Typically, air flow, in cubic feet per minute, is measured at pressure differentialsof 0.05 to 0.30 inches H2O depending on the capacity of the air handling equipment andother parameters. From data taken during the test, an overall air change per hour (ACH)figure can be established--generally the air flow (in ACH) at 0.20 inches H 2O divided by20.

Also, the American Society of Heating, Refrigeration, and Air-Conditioning Engineers(ASHRAE) publication 119-1988, Air Leakage Performance for Detached Single-FamilyResidential Buildings, provides performance requirements for air leakage of residentialbuildings to reduce the air infiltration load.

Infiltration can be significantly influenced by air and vapor barriers. Although eachinfluences infiltration, their purposes are significantly different. Air barriers function to limitthe flow of air into or out of a building. Vapor barriers serve to limit moisture flowing fromthe conditioned space into the building envelope. Air barriers should be placed over theinside face of frame members in the ceiling, and either inside or outside of the framingin exterior walls. If used also as a vapor barrier, air barriers must be placed between theinsulation and interior wall gypsum to meet material requirements for vapor barriers.

For most construction applications, continuous polyethylene sheet or wallboard with foilbacking meets vapor barrier requirements. An older method for providing an unbroken

vapor barrier was to use a polyethylene sheet. More current practices emphasize sealingelectrical and plumbing openings in the top plate and holes around ceiling fans andfixtures. Kraft paper backed batt insulation forms a satisfactory vapor barrier if properlyinstalled and the paper on the batt meets vapor rating requirements. Batts in framingcavities should be fastened to the face of the conditioned side of the framing memberrather than the sides, as is common practice. The batt ends should also be fastened ina similar manner to ensure a continuous barrier around the wall cavity.

3-10


23/62



Ventilation

Ventilation has a variety of impacts on residential energy consumption. Ventilation playsa major role in eliminating moisture buildup in and around the building envelope, andenhancing air quality. In attics, crawl spaces, and walls, adequate ventilation caneliminate moisture buildup which can lead to structural or insulation damage. Ventilationin attic spaces can effectively lower summer cooling costs by as much as 10 percent.For example, thermostatically-controlled attic ventilation systems are a key feature of thehighly energy-efficient Florida homes identified in Section 3.3. Other important aspectsof the ventilation issue are living space cooling and air quality control.

Ventilation can be an important source of living space cooling under optimal climatic

conditions. In climates noted for clear skies, low humidity, and relatively large nocturnaltemperature changes, natural or mechanical ventilation (also called a whole house fan)can minimize or replace seasonal mechanical cooling, and operates at about 10 percentof the cost of mechanical air conditioning. Climatic conditions experienced at MountainHome AFB support the whole house fan concept. Additionally, natural ventilation, whilegenerally not reliable due to its dependency on surface air flow, should be a part of thedesign consideration and included as a cooling and ventilation option for occupants touse.

Ventilation also plays a particularly important role in air quality that is usually counter toECMs. On one hand, energy conservation is significantly aided by limiting infiltration, and

super energy-efficient homes strictly limit infiltration as an energy saving technique. Onthe other hand, adequate ventilation (partially achieved through infiltration) is necessaryto minimize contaminants and provide sufficient air quality. In very tightly constructedhomes, an energy recovery ventilator (ERV) offers a solution when used in connectionwith a contamination sensor. The sensor activates the ERV which draws out conditionedbut contaminated air, which is then used to heat or cool incoming air as the seasonrequires. In homes with greater infiltration rates, properly designed local exhaust fans inthe kitchens and baths coupled with correctly sized central heating and air conditioningsystems are highly capable of ensuring adequate air quality. A minimum of .35 airchanges per hour is required in housing planned for Mountain Home AFB.

3.3.2 Mechanical Equipment

Natural gas heating with electric air conditioning has been identified as the type of heatingand air conditioning systems acceptable to meet the energy budget requirements in thisManual. Natural gas heating amply meets energy budget requirements, as well asgeneral energy design considerations. As a minimum, contractors will ensure the

3-11


24/62



following energy efficiency standards for residential space conditioning systems areincluded as part of their proposals.

l

l

l

l

l

l

l

l

l

l

l

l Two-story units require separate thermostat controls for upstairs and downstairs

Space Conditioning Requirements

Heating and cooling load calculationsEquipment sized in accordance with load calculationsEquipment certification with DOE Appliance Efficiency StandardsDucts installed, sealed, and externally insulated to a minimum level of R-7Equipment installed in accordance with manufacturers instructionsPilotless ignition for gas-fired equipmentSetback thermostats

Minimum equipment efficienciesDamper controls on exhaust systemsCentral gas furnaces with minimum AFUE of at least 90 percentCentral air conditioners with capacities less than 65,000 Btus per hour require aminimum SEER of 10.0

Mechanical Equipment Controls

A key element in residential energy conservation is the lifestyle of the occupants.

Adjusting the thermostat to accommodate departures from a residence, such as dailywork and school schedules and sleeping periods at night, can result in energy savingsof 10 to 20 percent. Automated controls make the temperature adjustments convenient,and can be a cost effective ECMs. This Manual includes provisions for setbackthermostats on residential heating and cooling systems. Also required is a clockmechanism that turns off the system during periods of non-use, and allows the occupantsat least two periods in 24 hours to automatically turn up or turn down the thermostatsetting.

3.3.3 Domestic Hot Water

For the two types of residences identified in the RFP, energy consumption for domestichot water (DHW) is projected to consume approximately one-half the total energyrequirement for heating and cooling. Figure 2.1 in Chapter Two provides a projection oftotal energy use in Mountain Home AFB housing. DHW, or the water produced by thehot water heater, consumes 20 percent of the total requirement; heating and cooling areprojected to generate 44 percent of total demand.

3-12


25/62



In general, domestic hot water heaters should have either an R-12 external insulationblanket or be certified by the DOE as not requiring a blanket. DHW piping also requiresinsulation from R-4 to R-6 depending on the pipe diameter. For domestic hot water pipe,diameters less than 2 inches use R-4. R-6 is used for diameters over 2 inches. Coolingsystem piping used with temperatures below 55F must be similarly insulated.

3.4 Solar Applications

The energy crises of the 1970s had several major and long lasting impacts. Perhaps themost immediate was a keen sense of public awareness of the need to conserve energy,in particular non-renewable resources. For a substantial period of time during the 1970s,

the public was faced with the distinct possibility of disruption of critical petroleum imports.The cost of all energy sources rose dramatically. In the 1960s, residential ECMs werenot a major factor in home design, and in many areas even minimal wall or ceilinginsulation was not used. Resistance strip heating was commonplace. During the 1970s,energy costs soared overnight and so did average monthly utility costs. Heating billsfrom $200 to $400 per month were not at all unusual in areas of the North and Northeast.From the sense of awareness and concern of the 1970s, a need arose to find ways tosave energy in residential buildings. As a result, considerable effort was placed on ECMsand solar applications, and residential design and construction techniques were changedin a fundamental way. The energy-efficient homes cited in Chapter Three underscore thetruly significant advances made in residential energy conservation made over the last 20

years.

Solar Applications are described below emphasizing passive solar design. As in Section3.3, Conventional Design Considerations, solar energy conservation applications that arepractical, reliable, and cost effective are highlighted.

3.4.1 Passive Solar Considerations

Passive solar heating deals primarily with the direct gain of energy as the suns rays passthrough glass and warm interior surfaces. These interior surfaces store energy

throughout the day, then release the stored energy at night. In contrast, active solarheating uses collectors and separate storage volumes to provide heating over time. Inpassive solar heating applications, the major consideration involves ways to allow solarradiation to enter the building envelope in the winter and exclude it in the summer. Otherconsiderations involve the design and placement of thermal mass areas to optimize thestorage and release of energy. The key factors of site planning and interior design areindispensable elements in passive solar applications.

3-13


26/62



3.4.2 Site Planning

Properly orienting a residence on a site to take advantage of passive solar opportunitiescan substantially reduce energy consumption. The long axis of the house should beoriented in an east-west fashion, with principal wall areas facing north and major glassareas facing south. This orientation will maximize exposure to the winter sun, as well asminimize the effects of the summer sun.

During the summer, the sun rises at a low angle providing strong heating to the eastfacing of the residence. As the sun rises, it assumes an almost vertical position at solar

noon. With adequate roof overhang and internal shading, the effects of the summer sunon the south side windows can be effectively controlled. During the afternoon, the westfacing of the house receives full solar exposure. Figure 3.9 shows the relative angles ofthe sun in the summer and in the winter.

Summer Sun Angie Winter Sun Angle

Figure 3.9: Summer and Winter Sun Angles for Southern Idaho

3-14


27/62



During the winter, the sun remains relatively low on the horizon and moves through the

solar noon providing extensive direct sunlight to the south side of the building. Figure3.10 shows the relative influence of sun angle on solar gain.

Figure 3.10: Solar Gain in Summer and Winter in Southern Idaho

Solar collection apertures should be free from shadows from other buildings or structuresthat would reduce solar access in the winter. However, vegetation in the form of

deciduous trees can provide effective summer shading for solar apertures, particularlyeast and west facings. In the winter, the deciduous trees loose their leaves allowingrelatively unimpeded solar access to the building.

3-15


28/62



3.4.3 Interior Design

Interior design is a critical element in determining passive solar effectiveness. Thefollowing three elements of interior design - thermal mass, interior zones, and solaraperture design - are examined from a passive solar standpoint.

Thermal Mass

Thermal mass serves to store energy as a building is warmed, and then releases thatenergy as the building cools. Thermal mass acts as a moderator by slowing internaltemperature variations, thereby reducing energy requirements. In passive solar designs,

thermal mass for heating purposes must be exposed to sufficient direct or indirectsunlight to be effective. Therefore, the location, shape, and material content of thethermal mass must be carefully selected. Typical thermal mass materials includeconcrete, tile, brick, or other materials with high interior mass capacity ratings. Examplesof thermal mass are shown in Figure 3.11.

Figure 3.11: Examples of Thermal Mass

3-16


29/62



The amount of thermal mass required for effective passive solar residences varies with

individual design. However, as a general rule for slab floor construction, thermal massshould be equivalent to 25 percent of the ground floor area of the building. For raisedconstruction, thermal mass should be equivalent to 10 percent of the ground floor area.Thermal mass walls are most effective with a high surface thermal absorptivity (greaterthan 80 percent).

Interior Zones

The effective design of passive solar heating systems must consider heat transferproblems associated with interior thermal zones. Interior thermal zones are generally

formed by walls that separate rooms, thereby causing temperature differentials. Thesetemperature differentials can cause problems with occupant comfort unless adequatedesign consideration is given to heat transfer methods such as window location, zonalheat coupling, and thermal mass considerations.

Solar Aperture Design

Solar aperture design deals primarily with controlling solar access to the building interior.In regard to winter heating situations, the objective of aperture design is to maximize solarcontact with thermal mass and selectively warm interior surfaces. In the summer, effective

aperture design limits solar access, allowing thermal mass to slow the warming processand provide a comfortable living space on an otherwise warm day. The principalconsiderations in aperture design deal with fenestration features that provide solar accessto thermal mass areas, and the placement of thermal mass to take full advantage of solarheating.

Direct Gain Windows. Direct gain windows are integral to the passive solar process withsize, type, and location being the primary variables. For passive solar design homes, theminimum south facing area is 6.4 percent, and the maximum total non-south facing areais 9.6 percent. The maximum U-Value for direct gain windows is 1.10. Direct gainwindows should be located to maximize thermal zoning and thermal mass design. Single

pane windows are recommended for direct solar gain applications.

Daylighting. Daylighting refers to the sunlight that enters solar apertures in the solarheating process. This beneficial side effect of passive solar design can also be aneffective ECM in reducing costs associated with lighting.

3-17


30/62



In summary, Chapter Three contains information about ECMs that are applicable to the

residential housing identified in the RFP. In Chapter Four, information is presented on thecomputation of points to be used in the evaluation of each housing prototype submitted.

3-18


31/62



Chapter Four

Energy Calculation Procedures

4.1 Overview

This chapter provides information on the procedures to determine compliance with theenergy budget established in Chapter Two. The procedure to determine compliance is

based primarily on completion of a point system worksheet which is attached at the endof this chapter. The energy budget and points system worksheets were compiled usingCOSTSAFR and CAPS computer programs developed by Pacific Northwest Laboratoryunder contract with the DOE. Both programs were developed for use by federal agenciesas a part of the DOES Interim Energy Conservation Mandatory Performance Standardsfor New Federal Residential Buildings. The forms used to determine compliance willhereafter be referred to as the point system.

Contractors must complete the worksheets for each prototype residence submitted forconsideration. Designers select ECMs that earn credit in the points system. ECMsinclude insulation levels, window type and area, infiltration levels, HVAC equipment, and

water heating. The cumulative points from all ECMs must equal or exceed a pre-established required point total to comply with the standard.

4.2 Definition of Points

Points are proportional to dollars of life cycle energy savings, and are relative to the worst(least energy efficient) level for each ECM. For example, a point total of 53 indicates thatthe prototype being considered generates a life cycle cost saving of $5,300 in current-year dollars over the same prototype with minimum level ECMs. The absolute value ofthe points for any ECM must be taken in relative, marginal context. For example, the

points awarded to foundation measures tend to be much higher than the points awardedto ceiling and wall insulation because floor measures are compared to the very inefficientminimum level of R-O (no insulation). In contrast, the minimum level for ceiling and wallinsulation is R-11. The energy savings relative to R-O insulation are much larger than theenergy savings relative to R-11 insulation. However, the difference in points for the

foundation ECMs may be small. Therefore, the gain in points for increasing thefoundation conservation levels may have little impact on the overall point total. The leastenergy-efficient levels for all components always have points equal to 0.0. For Mountain

4-1


32/62



Home AFB, there are two categories of residences identified for points computation:Single-Family Ranch Style Houses, and Two-Story Duplex Houses.

Please note that negative numbers are possible for some, ECMs. For example, heat-absorbing glass (Section F of the point system) and reflective glass (Section G of thepoint system) can have negative points for heating because they negate potential solarheating benefits of clear glass.

4.3 Structure of Point System

The ECMs in the point system can be thought of as two independent groups. Theprincipal group includes heating and cooling ECMs. This group contains space

conditioning measures (Sections A through N) and HVAC equipment measures (Section0). The space conditioning ECMs consist of the envelope or building shell measures,and are modified in the HVAC section to account for HVAC efficiency. Therefore, achange in points for any envelope ECM does not directly translate to an equal changein total points. The secondary group of ECMs includes DHW. A measure from each ofSections A, B, C, D, and E must always be chosen. All other space conditioningcategories (Sections F through N) are optional, unless specified otherwise by the AirForce.

The point system begins with the ceiling, wall, and floor insulation levels (Sections A, B,and C, respectively). In Section B, either the wood frame wall or thermal mass wall

measure should be selected. Section D covers infiltration (leakage of air into the building)which is based on average, tight, or very tight construction. Appendix A contains aninfiltration worksheet which should be used to determine infiltration levels. Section Ecovers the window points, and is based on three factors: window area, glazing layers,and sash type.

Sections F through L cover various window measures that can be used to modify theabsolute contribution of the windows to the point total. The sun tempered measure(Section I) accounts for window orientations more favorable than the default, whichassumes that windows are equally distributed. Sections J, K, and L present points formoveable night insulation for windows. Section M is for sunspaces, and Section N is for

light colored roofs.

Section O uses the heating and cooling total points from Sections A through N, SpaceConditioning Total, in equations for the HVAC equipment to determine the Total Heatingand Cooling Points.

4-2


33/62



The DHW ECMs are independent of all other ECMs. Their points are combined with theTotal Heating and Cooling Points in the calculation of TOTAL POINTS.

4.4 Interpolating Between Energy Conservation Measures

ECMs that fall between levels in the point system can be awarded points throughstandard interpolation techniques. For example, if you propose a wall insulation level ofR-16 and only R-13 and R-19 appear in the point system, you can linearly interpolate tocalculate the appropriate points. In this case, an R-16 wall is the average of the pointvalues for R-13 and R-19.

4.5 Compliance with the Energy Budget

The total points are calculated based on the selections you make. If the calculated totalequals or exceeds the required points total, the proposed design complies with theenergy budget. If the calculated total is less than the required total, you must go backto the design measures and decide which one(s) to tighten. This process continues untilthe revised point total equals or exceeds the required total.

4.6 Point System

The point system is a form generated by the DOE (and modified by Delta ResearchCorporation). The form is completed by the contractor to show compliance with theenergy budget developed specifically for Mountain Home AFB. You must prepare aseparate six-page form for each allowable housing type (refer to the RFP). Circle thespecific ECMs incorporated in your design, and copy the points assigned to these levelsin the appropriate space on the form. Add up the points to obtain the point total for theproposed design.

The proposed design must satisfy the energy budget. If your design does not meet orexceed the energy budget, evaluate the design, determine which elements of theproposed design are causing poor performance, and redesign the unit.

REMEMBER TO COMPLETE THE SIX-PAGE FORM FOR EACH HOUSING UNIT TYPE.

4-3


34/62



4.7 Point System Instructions

For wall insulation, either wood frame walls or thermal mass walls may be selected forsite-built houses. The points for the thermal mass wall ECM depend on the R-value ofthe insulation, the heat capacity of the heavyweight material, and the location of theinsulation.

In Section E of the example form, the window area is the percentage of window area asa fraction of the total conditioned floor area. For example, a house with 1,000conditioned square feet and 120 square feet of window area has a 12% window area.The sash type can either be aluminum with thermal break, or wood/vinyl (vinyl isconsidered to be equivalent to wood). Sections F through L cover window measures thatcan then be used to modify the absolute contribution of the windows to the point total.

Window area, glazing layers, and sash type in these sections must be consistent withthose selected in Section E.

In Section I of the example form, the points are determined for sun tempered designs bycompleting three equations for both heating and cooling. Note that this section iscompleted in addition to Section E, only if the window orientation is not evenly dividedamong the four cardinal directions. In Equation A of Section I, the area of eachorientation is entered as a fraction of the total window area. For example, if 20% of thewindows are on the north side, then the entry above N is 0.20. In Equation B of SectionI, the quantity X calculated in Equation A is multiplied by the total window areapercentage and the shading coefficient (SC). The total window area percentage is

entered as a fraction of one. For example, if the total window area is 10% of the heatedfloor area, then the entry above %AREA is 0.10. If the actual shading coefficients arenot available from manufacturers data, use the data in Table 4.1, Window ShadingCoefficients.

Window Shading Coefficients

Glass Type Single Layers Double Triple

Clear 1.00 0.88 0.79

Heat-Absorbing 0.77 0.64 0.56

Reflective 0.40 0.31 0.30

Low-E - 0.78 0.70

Table 4.1: Window Shading Coefficients

Equation C of Section I uses the quantity "Z" from Equation B in two different locations.

By using this equation, you can determine the heating and cooling points for the suntempered section.

4-4


35/62



NOTE: Totals for Sections A through N are entered on page 5 under SpaceConditioning Total. Add the heating and cooling points from the first four pages of the

example form and the top of page 5 to get a separate total for heating and cooling.Section O uses the Space Conditioning Totalfor heating and cooling in equations for theHVAC equipment to determine the Total Heating and Cooling Points.

In Section O, first enter the appropriate space conditioning total in the parentheses inStep A (heating) and Step C (cooling). Complete the equations in Steps A and C, andinsert the results in the parentheses above the letters X and Y in Steps B and D,respectively. The efficiency of the heating and cooling equipment must also be enteredin Steps B and D. In Section O, use the AFUE and SEER values from the Federal EnergyLabel, which is required for all residential furnaces, and air conditioners.

You may choose any of the different types of heating equipment listed in Step B. It isrecommended that all allowable equipment be tried and the heating points compared.Equipment with higher fuel costs will often make it extremely difficult to meet the requiredpoint total.

The numbers obtained from Steps B and D for both heating and cooling in Section O arethe Total Heating and Cooling Points, and are rewritten at the bottom of page 5 of thepoint system form. The Total Heating and Cooling Pointson the bottom of page 5 areonly the points from Section 0.

The DHW point system on page 6 applies to all equipment types. The equations for the

DHW heaters are based on the number of bedrooms in each unit. To calculate the pointsfor this page, enter the Energy Factor in the blank above EF on the appropriate line.The DHW heater points are added and the total is entered in the space at the middle ofpage 6.

To determine the TOTAL POlNTSon page 6, copy the heating point total and the coolingpoint total from the bottom of page 5 into the appropriate blanks. Also, copy the TOTALDHW from page 6. Calculate the TOTAL POINTS by adding the three values. The TOTALPOINTS must be equal to or greater than the MINIMUM REQUIRED POINT TOTAL shown

just beneath the TOTAL POINTS. Note that the required points vary with the number ofbedrooms because of varying hot water usage. If the points are less than the MINIMUM

REQUIRED POINT TOTAL, you must make adjustments by changing some of the ECMlevels to meet the criteria. If the points are greater than the minimum total, you can usethe selected ECMs, or adjust the ECMs to lower costs.

The EST/MATED UNIT ENERGY COSTover 25 years is calculated and appears at thebottom of page 6. Enter the conditioned floor area in square feet. The EST/MATED UNITENERGY COSTis shown in units of hundreds of dollars.

4-5


36/62



4.8 Point System Example

In order to better illustrate how the point system form is completed, following is anexample of ECM categories and values. Compare these ECM values against the examplepoint system form on the following pages.

A

B

C

D

E

Ceiling Insulation

Wall Insulation

Floor Type & Insulation

Infiltration

Window Type and Area

F,G,H Heat-Absorbing, Reflective,or Low-Emissivity Glass

I Sun Tempered Design

J,K,L R-1, R-3, R-5Moveable Insulation

M

N

O

Sunspace

Light Roof Color

HVAC EquipmentHeating Equipment

Cooling Equipment

DHW Heater

. . . R-30

. . . R-19

. . . slab on grade: R-10 for 2 Ft.

. . . average

. . . double glass

. . . aluminum sash + thermal break

. . . 12% window area

. . . no

. . . yes

. . . no

. . . no

. . . no

. . . natural gas furnace, AFUE 0.90

. . . air conditioner, SEER, 10.0

. . . gas, Energy Factor 0.60

4-6


37/62

POINT SYSTEM FOR: Single-Story Ranch Style HousesFEDERAL HOUSING PROCUREMENT FOR MOUNTAIN HOME AFB, ID pg. 1

Project Title: Mountain Home AFB REEM Design #: 1

Unit Type: EXAMPLE

Proposer:

A: CEILING INSULATION POINTS

Heating Cooling

R-49 6.3 0.6R-60 6.6 0.9

Points for A:Heating

El: WALL INSULATION POINTS (Select either Wood Frame or Thermal Mass Walls)

Wood Frame Walls

R-24

Heating

3.7

Cooling

0.2

R-26 4.1 0.2Points for B:

Heating Cooling

Thermal Mass Walls (Outside, Inside, Mixed: location of insulation)

Heat Capacity H

Outside -13.6 -0.8 -3.34 Inside -13.6 -1.3 -3.3

Mixed -13.2 -1.3 -3.0

Outside -13.4 -0.4 -3.26 Inside -13.4 -1.0 -3.2

Mixed -13.0 -0.8 -3.0

Outside -13.2 -0.1 -3.18 Inside -13.3 -0.8 -3.2

Mixed -12.9 -0.5 -2.9

10Outside -13.2 0.1 -3.0Inside -13.2 -0.6 -3.1

Mixed -12.8 -0.2 -2.8

12

Outside -13.1Inside -13.1Mixed -12.8

14


R-4C

0.3-0.50.0

0.4-0.3

0.2

H

-3.0-3.1

-2.8

-3.0-3.1-2.8

C HR-8 R-12

C HR-16

C HR-20

C

0.3-0.1

0.0

0.4 0.5 2.3 0.6 3.4 0.70.4 0.1 2.2 0.2 3.4 0.2

0.6 0.3 2.4 0.4 3.6 0.5

0.5-0.0

0.2

0.5 0.7 2.3 0.8 3.5 0.8

0.4 0.1 2.3 0.2 3.4 0.2

0.6 0.4 2.5 0.5 3.6 0.5

0.7 0.5 0.8 2.4 0.9 3.5 0.9

0.1 0.4 0.2 2.3 0.2 3.4 0.2

0.4 0.7 0.5 2.5 0.5 3.6 0.5

0.8 0.6 0.9 2.4 0.9 3.5 0.9

0.1 0.5 0.2 2.3 0.2 3.4 0.2

0.5 0.7 0.6 2.6 0.6 3.7 0.6

0.9 0.6 1.0 2.5 1.0 3.6 1.0

0.2 0.5 0.2 2.3 0.3 3.4 0.2

0.6 0.8 0.6 2.6 0.6 3.7 0.6

1.0 0.6 1.0 2.5 1.0 3.6 1.0

0.2 0.5 0.3 2.3 0.3 3.4 0.2

0.6 0.8 0.6 2.6 0.6 3.7 0.6

Points for B: 0 0Heating Cooling


38/62

POINT SYSTEM FOR: Single-Story Ranch Style HousesFEDERAL HOUSING PROCUREMENT FOR MOUNTAIN HOME AFB, ID

(continued) pg. 2

C: FLOOR INSULATION POINTS

Heating Cooling

Basements

Not Applicable

Crawl Space

Not Applicable

Slab on Grade

Points for C:Heating Cooling

D: INFILTRATION POINTSHeating Cooling

Very Tight 11.0 0.1Points for D:

Heating Cooling

E: WINDOW TYPE AND AREA ("10%" = 10% of heated floor area)

Window Area: 10% 12% 14%H C H-C H C

Single Glass

Alum. NA NA NA NA NA NAAL & TB NA NA NA NA NA NAW o o d / V i n y l N A N A NA NA NA NA

Double GlassAlum. NA NA NA NA NA NA

AL & TB 11.0 3.3 10.7 2.4

Wood/Vinyl 11.7 3.3 11.6 2.9 11.5 2.4Triple Glass

Alum. NA NA NA NA NA NAAL & TB 12.3 3.6 12.5 3.2 12.5 2.8Wood/Vinyl 12.9 3.6 13.2 3.2 13.4 2.8

16%H C

NA NA

NA NA

NA NA

NA NA

10.4 1.9

11.4 2.0

NA NA12.6 2.4

13.6 2.4

18%H C

NA NANA NA

NA NA

NA NA

10.0 1.4

11.1 1.4

NA NA

12.6 1.913.7 1.9

20%H C

NA NA

NA NA

NA NA

NA NA9.7 0.9

10.9 0.9

NA NA

12.5 1.513.8 1.5

Points for E:Heating Cooling


39/62


(continued) pg. 3

F: HEAT-ABSORBING GLASS (10% = 10% of heated floor area)

Window Area: 10% 12% 14% 16% 18% 20%H C H C H C H C H C H C

Single Glass NA NA NA NA NA NA NA NA NA NA NA NADouble Glass

-1.1 0.8 -1.3 1.0 -1.4 1.2 -1.4 1.4 -1.5 1.6 -1.5 1.8Triple Glass -1.2 0.7 -1.4 0.9 -1.5 1.0 -1.6 1.2 -1.7 1.4 -1.7 1.6Points for F:

Heating CoolingG: REFLECTIVE GLASS ("10%" = 10% of heated floor area)

Window Area: 10% 12% 14%H C H C H C

Single Glass NA NA NA NA NA NADouble Glass -2.6 1.7 -3.0 2.0 -3.2 2.5Triple Glass -2.9 1.4 -3.3 1.8 -3.7 2.1

H: LOW-E GLASS ("10%" = 10% of heated floor area)

Window Area: 10% 12% 14%H C H C H C

Single Glass NA NA NA NA NA NADouble Glass 1.9 0.4 2.7 0.6Triple Glass 0.8 0.3 0.9 0.4 1.1 0.5

16% 18% 20%H C H C H C

NA NA NA NA NA NA-3.4 2.9 -3.6 3.4 -3.7 3.9-4.0 2.5 -4.3 2.9 -4.5 3.3

Points for G:Heating Cooling

16% 18% 20%H C H C H C

NA NA NA NA NA NA3.2 0.7 3.6 0.8 4.1 0.91.4 0.6 1.6 0.6 1.8 0.7

Points for H :Heating Cooling

I: SUN TEMPERED (Calculate points by using equations A, B and C)

Heating PointsA: (Enter fraction of total window area for the 4 orientations: N, E, S, & W)

( 49.6 x ___ + 97.2 x ___ +151.0 x___ + 79.7 x___) - ( 94.4 ) = ___N E S W X

B: (%Area = 0.10 for window area, 10% of heated floor area)

______ X x 1.54 = ____X

___ x _______SC %AREA Z

C: ___x [ 0.647 + ( 0.005 x ____ ) ] = 0Z Z H

Cooling Points

A: (Enter fraction of total window area for the 4 orientations: N, E, S, & W)

( -10.3____ x -21.2 x ____-20.9 _____ x -28.3 x ____N E S W

) + ( 20.2 ) = ____

X


x xX

_____ x 1.54 = _____SC %AREA Z

C: ____Z

x [ 0.487 + (0.043 x ____

Z

) ] = 0

C


40/62


(continued) pg. 4

J: R-1 MOVEABLE INSULATION ("10%" = 10% of heated floor area)No cooling points for moveable insulation

Window Area: 10% 12% 14% 16% 18%

H H H H H

Single GlassAlum. NA NA NA NA NA

AL & TB NA NA NA NA NA

Wood/Vinyl NA NA NA NA NA

NA NA NA NA NADouble GlassAlum.AL & TB 0.7 0.8 1.0 1.1 1.3Wood/Vinyl 0.6 0.7 0.8 1.0 1.1

NA NA NA NA NATriple Glass

Alum.AL & TB 0.4 0.5 0.6 0.6 0.7Wood/Vinyl 0.3 0.4 0.4 0.5 0.5

NA0.80.6

Points for J:

Heating

20%H

NA

NANA

NA

1.4

1.2

K: R-3 MOVEABLE INSULATION (10% = 10% of heated floor area)No cooling points for moveable insulation

Window Area: 10%H

Single GlassAlum. NAAL & TB NAW o o d / V i n y l N A

Double GlassAlum.AL & TB 1.3 1.6 1.8 2.1 2.3 2.6

Wood/Vinyl 1.1 1.3 1.5 1.8 2.0 2.2

12% 14% 16% 18% 20%

H H H H H

NA NA NA NA NA

NA NA NA NA NA

NA NA NA NA NA

NA NA NA NA NA NA

NA NA NA NA NA NATriple Glass

Alum.AL & TB 0.8 1.0 1.1 1.3 1.4 1.6Wood/Vinyl 0.6 0.7 0.8 1.0 1.1 1.2

Points for K:Heating

L: R-5 MOVEABLE INSULATION ("10%" = 10% of heated floor area)No cooling points for moveable insulation

Window Area:

Single Glass

Alum.AL & TBWood/Vinyl

Double GlassAlum.

AL & TB

Wood/VinylTriple Glass

Alum.

AL & TB

Wood/Vinyl

10% 12% 14% 16% 18% 20%

H H H H H H

NA NA NA NA NA NANA NA NA NA NA NA

NA NA NA NA NA NA

NA NA NA NA NA NA

1.5 1.8 2.1 2.4 2.7 3.0

1.3 1.6 1.8 2.1 2.3 2.6

NA NA NA NA

1.0 1.2 1.4 1.6

0.8 1.0 1.1 1.3

NA NA

1.8 2.01.4 1.6

Points for L:Heating


41/62


(continued) pg. 5

M: SUNSPACES (No cooling points for sunspaces)

w/ Glass Roof w/ Solid Roof

and Single Glass: 7.8

and Double Glass: 15.5

and Single Glass: 3.2and Double Glass: 7.8

Heating:

N: LIGHT ROOF COLOR (No heating points for roof color)Cooling:

For roof R-values below R-30 0.0

For roof R-values R-30 and above 0.0 Points:Cooling

SPACE CONDITIONING TOTAL (Total Sections A through N)HEATING COOLING

O: HVAC EQUIPMENTInsert SPACE CONDITIONING TOTAL for HEATING in the blank provided in equation A.

Note: Set all negative values for X to 0.0

B: Oil furnaces and boilers: DOES NOT APPLY

Natural gas furnace and boilers:

LPG furnaces and boilers: DOES NOT APPLY

Electric furnaces and baseboards: DOES NOT APPLY

Electric heat pumps: DOES NOT APPLY

Insert SPACE CONDITIONING TOTAL for COOLING in the blank provided in equation C.

Note: Set all negative values for Y to 0.0.

TOTAL HEATING AND COOLING POINTS(Rewrite selected points from section 0.)

Heating Cooling


42/62


(continued)

TOTAL DHW HEATER POINTS

pg. 6

GAS DHW HEATERS (Insert Energy Factors):

2 BR Units: 10.0 - [ 5.5/

3 BR Units: 18.1 - [ 10.0 / ( ) ] =

4 BR Units: 22.1 - [ 12.2 / ( ) ] =

EF DHW points

ELECTRIC DHW HEATERS: DOES NOT APPLY

TOTAL POINTS:

DHW TOTAL HEATING TOTAL COOLING TOTAL TOTAL POINTS

(from pg. 6) (from bottom of pg. 5) (from bottom of pg. 5)

MINIMUM REQUIRED POINT TOTAL

2-BR Units: 643-BR Units: 65

4-BR Units: 65

ESTIMATED UNIT ENERGY COST (for information only): This provides an estimate of the energy cost

over a 25-year life cycle for one unit (estimate given in hundreds of $).

heating & conditioned DHW Points (hundreds of $)cooling floor

points area


43/62

POINT SYSTEM FOR: Single-Story Ranch Style HousesFEDERAL HOUSING PROCUREMENT FOR MOUNTAIN HOME AFB, ID pg. 1

Project Title: Mountain Home AFB REEM

A: CEILING INSULATION POINTS

Design #:

Unit Type:

Proposer:

Heating Cooling

R-30 4.8 0.6R-38 5.7 0.7R-49 6.3 0.8R-60 6.8 0.9

Points for A:Heating Cooling

B: WALL INSULATION POINTS (Select either Wood Frame or Thermal Mass Walls)

Wood Frame Walls

R-19R-24R-26

Heating Cooling

2.5 0.13.7 0.24.1 0.2

Points for B:Heating Cooling

Thermal Mass Walls (Outside, Inside, Mixed: location of insulation)

Heat Capacity H

4

6

8

10

12

14

Outside -13.6

Inside -13.6

Mixed -13.2

Outside -13.4

Inside -13.4Mixed -13.0

Outside -13.2


Outside -13.2



Outside -13.0

Inside -13.0

Mixed -12.7

R-4 R-8C H C H

R-12C H

R-16C H

R-20C

-0.8 -3.3 0.3 0.4 0.5 2.3 0.6 3.4 0.7-1.3 -3.3 -0.1 0.4 0.1 2.2 0.2 3.4 0.2

-1.3 -3.0 0.0 0.6 0.3 2.4 0.4 3.6 0.5

-0.4 -3.2 0.5 0.5 0.7 2.3 0.8 3.5 0.8-1.0 -3.2 -0.0 0.4 0.1 2.3 0.2 3.4 0.2-0.8 -3.0 0.2 0.6 0.4 2.5 0.5 3.6 0.5

-0.1 -3.1 0.7 0.5 0.8 2.4 0.9 3.5 0.9-0.8 -3.2 0.1 0.4 0.2 2.3 0.2 3.4 0.2

-0.5 -2.9 0.4 0.7 0.5 2.5 0.5 3.6 0.5

0.1 -3.0 0.8 0.6 0.9 2.4 0.9 3.5 0.9

-0.6 -3.1 0.1 0.5 0.2 2.3 0.2 3.4 0.2

-0.2 -2.8 0.5 0.7 0.6 2.6 0.6 3.7 0.6

0.3-0.50.0

0.4-0.3

0.2

-3.0 0.9 0.6 1.0 2.5 1.0 3.6 1.0

-3.1 0.2 0.5 0.2 2.3 0.3 3.4 0.2

-2.8 0.6 0.8 0.6 2.6 0.6 3.7 0.6

-3.0 1.0 0.6 1.0 2.5 1.0 3.6 1.0

-3.1 0.2 0.5 0.3 2.3 0.3 3.4 0.2

-2.8 0.6 0.8 0.6 2.6 0.6 3.7 0.6

Points for B:Heating Cooling


44/62


(continued) pg. 2

C: FLOOR INSULATION POINTS

Heating Cooling

Basements

Not Applicable

Crawl Space

Not Applicable

Slab on Grade

R-10 (2FT) 28.0R-5 (4FT) 28.4

R-10 (4FT) 29.5

D: INFILTRATION POINTS

AverageTightVery Tight

Heating0.05.5

11.0

5.05.1

5.1

Points for C:Heating Cooling

Cooling

0.0

0.10.1

E: WINDOW TYPE AND AREA ("10% = 10% of heated floor area)

Points for D:Heating Cooling

Window Area: 10%H

Single Glass

Alum. NA

AL & TB NA

Wood/Vinyl NA

Double Glass

Alum. NAAL & TB 11.0Wood/Vinyl 11.7

Triple GlassAlum. NAAL & TB 12.3Wood/Vinyl 12.9

C H12%

C

NA NA NA

NA NA NA

NA NA NA

NA NA3.3 10.9

3.3 11.6

NA NA3.6 12.5

3.6 13.2

NA NA2.9 10.72.9 11.5

NA NA3.2 12.5

3.2 13.4

H

NA

NANA

14% 16% 18% 20%C H

NA NA

NA NA

NA NA

NA NA2.4 10.42.4 11.4

NA NA2.8 12.6

2.8 13.6

C H

NA NA

NA NA

NA NA

NA NA1.9 10.0

2.0 11.1

NA NA2.4 12.6

2.4 13.7

C H C

NA NA NA

NA NA NA

NA NA NA

NA NA NA1.4 9.7 0.9

1.4 10.9 0.9

NA NA NA

1.9 12.5 1.5

1.9 13.8 1.5

Points for E:Heating Cooling


45/62

POINT SYSTEM FOR: Single Story Ranch Style HousesFEDERAL HOUSING PROCUREMENT FOR MOUNTAIN HOME AFB, ID

(continued) pg. 3

F: HEAT-ABSORBING GLASS (10% = 10% of heated floor area)

Window Area: 10% 12% 14% 16% 18% 20%

H C H C H C H C H C H C

Single Glass NA NA NA NA NA NA NA NA NA NADouble Glass

-1.1 0.8 -1.3 1.0 -1.4 1.2 -1.4 1.4 -1.5 1 . 6 - 1 . 5 1 . 8

N A NA

Triple Glass -1.2 0.7 -1.4 0.9 -1.5 1.0 -1.6 1.2 -1.7 1.4 -1.7 1.6

Points for F:Heating Cooling

G: REFLECTIVE GLASS ("10%" = 10% of heated floor area)

Window Area: 10% 12% 14% 16% 18% 20%H C H C H C H C H C H C

Single Glass NA NA NA NA NA NA NA NA NA NA NA NA

Double Glass -2.6 1.7 -3.0 2.0 -3.2 2.5 -3.4 2.9 -3.6 3.4 -3.7 3.9Triple Glass -2.9 1.4 -3.3 1.8 -3.7 2.1 -4.0 2.5 -4.3 2.9 -4.5 3.3

Points for G:Heating Cooling

H: LOW-E GLASS ("10%" = 10% of heated floor area)

Window Area: 10% 12% 14%H C H-C H C

Single Glass NA NA NA NA NA NADouble Glass 1.9 0.4 2.3 0.5 2.7 0.6Triple Glass 0.8 0.3 0.9 0.4 1.1 0.5

16% 18% 20%H C H C H C

NA NA NA NA NA NA

3.2 0.7 3.6 0.8 4.1 0.91.4 0.6 1.6 0.6 1.8 0.7

Points for H:Heating Cooling

I: SUN TEMPERED (Calculate points by using equations A, B and C)

Heating Points


(49.6 x + 97.2 x + 151.0 x + 79.7 x ) - (94.4) =N E S W X


x x x 1.54 =

X SC %AREA Z

C:Z

x [ 0.647 + ( 0.005 x - ) ] =Z H

Cooling Points


( -10.3 x 21.2 x 20.9 x -28.3 xN E S W

) + ( 20.2 ) =X


x x x 1.54 =

X SC %AREA z

C : x [ 0.487 + ( 0.043 x ) ] =

Z Z C


46/62


(continued)

J: R-1 MOVEABLE INSULATION ("10%" = 10% of heated floor area)No cooling points for moveable insulation

Window Area: 10% 12% 14% 16% 18%

H H H H H

Single GlassAlum. NA NA NA NA NA

AL & TB NA NA NA NA NA

Wood/Vinyl NA NA NA NA NA

Double Glass

Alum.AL & TBWood/Vinyl

Triple GlassAlum.AL & TBWood/Vinyl

NA NA NA NA NA0.7 0.8 1.0 1.1 1.30.6 0.7 0.8 1.0 1.1

NA NA NA NA NA0.4 0.5 0.6 0.6 0.70.3 0.4 0.4 0.5 0.5

NA0.80.6

Points for J:

Heating

20%

H

NANANA

NA

1.4

1.2

K: R-3 MOVEABLE INSULATION (10% = 10% of heated floor area)No cooling points for moveable insulation

Window Area: 10% 12% 14% 16% 18% 20%

H H H H H H

NA NA NA NA NA NASingle Glass

Alum.AL & TB NA NA NA NA NA NA

W o o d / V i n y l N A NA NA NA NA NA

NA NA NA NA NA NADouble GlassAlum.AL & TB 1.3 1.6 1.8 2.1 2.3 2.6

Wood/Vinyl 1.1 1.3 1.5 1.8 2.0 2.2Triple GlassAlum. NA NA NA NA NA NAAL & TB 0.8 1.0 1.1 1.3 1.4 1.6Wood/Vinyl 0.6 0.7 0.8 1.0 1.1 1.2

Points for K:Heating

L: R-5 MOVEABLE INSULATION ("10%" = 10% of heated floor area)No cooling points for moveable insulation

Window Area:

Single Glass

Alum.

AL & TBWood/Vinyl

Double GlassAlum.

AL & TB

Wood/Vinyl

Triple Glass

Alum.

AL & TB

Wood/Vinyl

10% 12% 14% 16% 18% 20%

H H H H H H

NA NA NA NA NA NANA NA NA NA NA NA

NA NA NA NA NA NA

NA NA NA NA NA NA

1.5 1.8 2.1 2.4 2.7 3.0

1.3 1.6 1.8 2.1 2.3 2.6

NA NA NA NA1.0 1.2 1.4 1.6

0.8 1.0 1.1 1.3

NA NA

1.8 2.0

1.4 1.6

Points for L:

Heating

pg. 4


47/62

POINT SYSTEM FOR: Single Story Ranch Style HousesFEDERAL HOUSING PROCUREMENT FOR MOUNTAIN HOME AFB, ID

(continued)

M: SUNSPACES (No cooling points for sunspaces)

w/ Glass Roof w/ Solid Roof

and Single Glass: 7.8 and Single Glass:

and Double Glass: 15.5 and Double Glass:

Heating:

factor from above(________________) = x 0.01 x (___________________) = ______

sunspace length (ft) H

N: LIGHT ROOF COLOR (No heating points for roof color)Cooling:

For roof R-values below R-30 0.0

For roof R-values R-30 and above 0.0 Points:

SPACE CONDITIONING TOTAL (Total Sections A through N)

O: HVAC EQUIPMENT

pg. 5

3.27.8

Cooling

===== ======HEATING COOLING

Insert SPACE CONDITIONING TOTAL for HEATING in the blank provided in equation A.

A: 119 - [ 1.546 x (_____________) ] = ________H E A T I N G X

Note: Set all negative values for X to 0.0

B: Oil furnaces and boilers: DOES NOT APPLY

Natural gas furnace and boilers:

77 - [ 0.485 x ( _________) / (_______) ] = ________X A F U E H

LPG furnaces and boilers: DOES NOT APPLY

Electric furnaces and baseboards: DOES NOT APPLY

Electric heat pumps: DOES NOT APPLY

Insert SPACE CONDITIONING TOTAL for COOLING in the blank provided in equation C.

C: 26 - [ 2.055 x (________) ] =COOLING Y

Note: Set all negative values for Y to 0.0.

D: 14 - [ 4.867 x ( ) =) / (Y S E E R C

TOTAL HEATING AND COOLING POINTS(Rewrite selected points from section 0.) ======== ========

Heating Cooling


48/62

POINT SYSTEM FOR: Single-Story Ranch S

Documents

Residential Energy Evaluation Manual