Embed Size (px)
Citation preview
S T R A T E G I E S F O R
E N E R G Y
E F F I C I E N T
R E M O D E L I N G
S E E R2 0 0 3C A S ES T U D YR E P O R T
S T R A T E G I E S F O R E N E R G Y E F F I C I E N T R E M O D E L I N G
S E E R 2 0 0 3C A S E S T U D Y R E P O R T
Submitted toNational Renewable Energy Laboratory1617 Cole BoulevardGolden, CO 80401-3393
Prepared byNAHB Research Center, Inc.400 Prince George’s BoulevardUpper Marlboro, MD 20774-8731
Authored byJoe WiehagenCraig Drumheller
March 30, 2004Updated April 12, 2004
Disclaimer
Neither the NAHB Research Center, Inc., nor any person acting in its behalf, makes anywarranty, express or implied, with respect to the use of any information, apparatus, method, orprocess disclosed in this publication or that such use may not infringe privately owned rights, orassumes any liabilities with respect to the use of, or for damages resulting from the use of, anyinformation, apparatus, method, or process disclosed in this publication, or is responsible forstatements made or opinions expressed by individual authors.
We would like to acknowl-edge the people and com-panies, without whose helpthis project would not havebeen a success. A specialthanks is extended to BillAsdal, both as the propertyowner and general contrac-tor/remodeler for his never-ending commitment toproducing a showcaseenergy retrofit home. Specialrecognition is also given tothe companies who madethis major undertaking pos-sible with generous technicaland material support:
AstroPower
Bergy Windpower
Crane Performance Siding
Eastern Insulation
Energy Services Group
Fineline Energy Solutions
Integrity Heating and Cooling
New Jersey Clean EnergyProgram
Rheem
SETS Systems
Simonton Windows
Smart Vent
Solargenix Energy
Tamarack Technologies
TechBuilt Systems
Therma – Tru Doors
U.S. GreenFiber
VanNatta Mechanical
Vanguard Piping Systems
Waterfurnace International
Whirlpool Corporation
Appreciation is also given tothe U.S. Department of Energy(DOE), Building AmericaProgram and the NationalRenewable Energy Labora-tory (NREL) technical advisors,for their consistent and com-petent support as well as theircommitment to improvingenergy efficiency in allhomes.
Thanks to the staff ofHousingzone.com who estab-lished, maintained andsupported the SEER websiteto widen the educationalcircle for energy efficiency inremodeling.
ACKNOWLEDGEMENTSS E E R 2 0 0 3 C
A S E S T U
D Y R E P O
R T
TABLE OF CONTENTS
1. INTRODUCTION ...................................................................................... 12. THE FIRST SEER PROJECT – A CASE STUDY IN ALL OR NOTHING ........ 23. SYSTEMS ENGINEERING APPLIED TO ENERGY EFFICIENCY
RETROFIT – CHALLENGES AND CHOICES ............................................ 34. BENEFITS TO HOME REMODELING PROJECTS THAT INCLUDE
ENERGY EFFICIENCY STRATEGIES ......................................................... 45. STRATEGIES FOR ENERGY EFFICIENCY IN REMODELING..................... 5
5.1 Wall Insulation System....................................................................................... 55.1.1 Wall Insulation – SEER Case Study ........................................................................................................................................ 5
5.2 Ceiling Insulation System.................................................................................. 85.2.1 Ceiling Insulation – SEER Case Study ................................................................................................................................ 8
5.3 Basement or Floor Insulation System............................................................... 85.3.1 Basement or Floor Insulation – SEER Case Study .................................................................................................. 9
5.4 Windows and Doors .......................................................................................... 95.4.1 Windows and Doors – SEER Case Study ........................................................................................................................ 9
5.5 Air Sealing ........................................................................................................ 105.5.1 Air Sealing – SEER Case Study ............................................................................................................................................... 10
5.6 Heating and Cooling Equipment ................................................................... 115.6.1 Heating and Cooling Equipment – SEER Case Study .................................................................................. 11
5.7 Water Heating System ..................................................................................... 135.7.1 Water Heating System – SEER Case Study ............................................................................................................... 14
5.8 Lights and Appliances .................................................................................... 155.8.1 Lights and Appliances – SEER Case Study ............................................................................................................... 15
5.9 Room Additions ............................................................................................... 155.9.1 Room Additions – SEER Case Study ................................................................................................................................ 15
5.10 Renewable Energy Systems ......................................................................... 165.10.1 Renewable Energy Systems – SEER Case Study .............................................................................................. 17
6. SUMMARY OF COST AND SAVINGS ESTIMATES ................................. 19ADDENDUM
FIRST SEER REMODEL SITE – LEBANON, NEW JERSEY......................... 23
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
LIST OF TABLES AND FIGURES
TABLESTable 1 – Insulated Siding Cost Comparison ......................................................................................................................... 6
Table 2 – Energy Efficiency Cost Summary .......................................................................................................................... 19
Table 3 – Summary of SEER Case Study Energy Use and Costs/Savings .............................................. 21
Summary of Economic Analysis Based on Energy Value Only ....................................................................... 22
FIGURESThe site of the “gut rehab” ....................................................................................................................................................................... 1
The “gut rehab” one year later ........................................................................................................................................................... 1
The main house on the same property ....................................................................................................................................... 2
Insulation blown into wall cavities ..................................................................................................................................................... 6
Blown cellulose insulation ........................................................................................................................................................................... 6
Insulated siding trim ........................................................................................................................................................................................... 7
Insulated siding ....................................................................................................................................................................................................... 7
Floor insulation between joists ............................................................................................................................................................... 8
Energy efficiency windows and door in cottage ............................................................................................................ 9
Air sealing around windows .................................................................................................................................................................. 10
Air barrier on outside of house .......................................................................................................................................................... 11
Ground source heat pump in conditioned space ..................................................................................................... 12
All duct joints sealed ..................................................................................................................................................................................... 12
Manifold plumbing system ..................................................................................................................................................................... 13
Hot water system in cottage ............................................................................................................................................................... 14
Solar thermal collector with PV panel for pump........................................................................................................... 14
Addition construction using foam panels .............................................................................................................................. 15
Ridge and eave supports for roof panels ............................................................................................................................. 16
Addition constructed in 6 hours ....................................................................................................................................................... 16
R-50 roof and R-30 wall panels .......................................................................................................................................................... 17
Ridge beam for roof support ............................................................................................................................................................... 17
PV system on cottage home .............................................................................................................................................................. 17
Aerial view of PV system .......................................................................................................................................................................... 17
Garage PV system for cottage home ...................................................................................................................................... 18
PV system inverters .......................................................................................................................................................................................... 18
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
1
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
INTRODUCTION
The goal of the Strategies forEnergy Efficiency in Remodel-ing (SEER)1 project is to pro-vide information, based onresearch and case studies, toremodelers and consumersabout opportunities to in-crease home energy perfor-mance. Opportunities toinclude energy efficiencyoften arise while undertakinggeneral remodeling work. Ofcourse, energy efficiencymay always be pursued as aremodeling project unto itselfto improve the comfort of thehome and reduce monthlyutility bills. A case study in themid-Atlantic region wasundertaken to develop and
test the application of energyefficiency (EE) strategies, toevaluate the benefits, and toidentify any weaknesses intheir design or application.Taken together as a system,the strategies provide oppor-tunities for energy and costsavings, increased durability,and increased comfort of theremodeled home.
1 The SEER project was developed by the NAHBResearch Center (NAHBRC) as part of the DOEExisting Buildings Program under the BuildingAmerica umbrella.2 The Building America program is sponsored bythe Department of Energy (DOE) through theNational Renewable Energy Laboratory (NREL).
The “gut rehab” one year later
This case study report exam-ines the technologies, meth-ods and installation ofspecific energy efficiencystrategies. The informationpresented here stems from a“gut rehab” of a house inrural New Jersey as part ofthe SEER project through theBuilding America ExistingBuildings Program2. A “gutrehab” project allows for
1
consideration of a widerange of energy efficiencystrategies and, accordingly, isa good basis of this initialeffort. As other remodelingprojects are undertaken theknowledge base will expandand become more complete.The evaluation of this exten-sive rehab project providesmany details of energyefficiency strategies that willlead to energy savings andcan be implemented byremodelers and consumersover months or years.
The site of the “gut rehab”
2
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
TTHE FIRST SEER PROJECT –A CASE STUDY IN ALL OR NOTHING
The gut rehab project devel-oped by remodeler Mr. BillAsdal is detailed in his sum-mary in the addendum andclearly demonstrates achoice between a remodel-ing “all-or-nothing” approach.The remodeler’s choice of thefull renovation of a home thatwould otherwise be destinedfor the landfill provides anopportunity to demonstratethe extent to which existinghousing can be made com-fortable and energy efficient– while remaining cognizantof the costs. The remodelerselected to fully renovate thehome and in so doing sal-vaged a building for contin-ued useful life. The SEERproject provided technicalservices to focus on theenergy efficiency aspects ofthe remodel and in so doingis estimated to decrease theheating and cooling energyconsumption by some 60%.
The case study remodelproject is part of a largerrenovation project to com-pletely rehab two homes anda barn on a section of farm-land in west central NewJersey. The smaller of thehomes, referred to as thecottage house, is 1,400square feet and has beenunoccupied for 10 years. Thehome, shown above, was
The main house on the same property
uninhabitable when pur-chased. Many of the energyefficiency concepts appliedto the cottage are also beingimplemented in the larger4,000 square foot home(which will serve as a Bed &Breakfast). The cottage housewill serve as the case studyhome to demonstrate strate-gies for an energy efficiencyremodel.
2
3
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
SYSTEMS ENGINEERING APPLIED TO ENERGYEFFICIENCY RETROFIT – CHALLENGES AND CHOICES
The Building America modelfor a systems engineeringapproach states that newhomes “can be cost effectiveto build as well as energyefficient to live in. In fact, theenergy consumption of newhouses can be reduced by asmuch as 50% with little or noimpact on the cost of con-struction through a systemsengineering approach.”3 Thistheory is practiced throughuse of new building materialsand systems as well as de-signs that can be serviced bysmaller heating and coolingsystems than used in typicaldesigns. Through the processoften termed “value engi-neering,” any increased costsin one area of construction(e.g., insulation) can be offsetby savings in another area(e.g., downsized furnace).
However, existing homespresent a larger challenge toimplementing a systemsapproach to energy effi-ciency. Because remodelingjobs typically involve fewersystems (e.g., wall, window,mechanical systems) thannew construction, it is moredifficult to make value-engineering tradeoffs. Inaddition, since remodelingjobs often involve a limitedbudget, it is typically moreexpensive to retrofit energyefficiency solutions than it isto include them in newconstruction.
Still, a systems approach toenergy efficiency remodelingcan create not only opportu-nities for energy savings, butalso improvements in durabil-ity and comfort. For example,existing homes may presentmore opportunities for the
have far fewer opportunitiesto directly reduce coststhrough construction tradeoffsexcept for gut rehabs and,possibly, attic/basementconversions and additions.Otherwise, the home alreadyhas selected framing, insula-tion, and heating and coolingequipment installed. In thesecases, the remodeling workmay focus on increasing theefficiency of a particularbuilding system as it is beingremodeled, or in some casesas additional work along withthe general remodeling effort.
3 Information on the Building America program’sSystem Engineering approach can be found athttp://www.eere.energy.gov/buildings/building_america/system.shtml.
3
selection of energy efficiencyupgrades since efficiencycan often be included withother work being performed.One benefit to includingenergy efficiency in existinghomes is that, often, peopleundertake extensive renova-tions with the intention ofstaying in the home for a longtime. Therefore, savings fromenergy efficiency detailsbecome an investment fromwhich they are likely to reapbenefits. In addition, a majoradvantage is the opportunityto improve comfort, espe-cially if the consumer hasdirect experience withuncomfortable conditions inthe home.
Unlike new constructionwhere energy efficiencyupgrades can directly reducecosts in other areas, theexisting home market will
Throughout the design and construction process,the systems engineering approach considersthe interaction between the building site,envelope, and mechanical systems, as well asother factors. It recognizes that features of onecomponent in the house can greatly affectothers and it enables the teams to incorporateenergy-saving strategies at no extra cost.System trade-offs, like the tightened shell thatenables an engineer to recommend a smallerHVAC system, can improve the quality andperformance of a home without affecting itscosts—to the builders or to the consumers.
Building America Program, Systems EngineeringResearch
4
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
4Many homes constructed 30or more years ago have littleor no insulation in the wallsand roof, single-pane win-dows that allow largeamounts of air and heat loss,and inefficient (by today’sstandards) hot water systems,space conditioning equip-ment, lighting, and appli-ances. All of these factorsresult in large amounts ofwasted energy and higherthan necessary utility bills.While lowering monthly utilityexpenses is often a primemotivation for improving ahome’s energy efficiency,there are numerous otherbenefits to improving energyefficiency that are not asoften considered. Thesebenefits include:
• Comfort – Leaky and poorlyinsulated older homes oftenfeel uncomfortable due tocold wall temperatures anddrafts from windows. Toaccommodate, manyhomeowners turn up thethermostat in the winter. Insummer, these homes areoften subjected to largesolar gains and high levelsof humidity (from theoutdoors), causing thehomeowner to turn thethermostat down. Whenthermostats are turned up(or down), in addition tothe additional energyrequired for heating andcooling the space, there isan associated increase inwasted energy throughduct or hydronic systemlosses. In addition, draftywindows, cold wall sur-faces, and poor duct
design often result in largetemperature variationsbetween rooms.
• Durability – Older, inefficienthomes are often subjectedto large indoor swings intemperature and humidity,causing wall and ceilingmaterials to swell and shrinkand reducing durability ofmaterials, paints, and caulk.In addition, to accommo-date the high-energyneeds of an inefficienthome, mechanical equip-ment may operatefrequently and for longerperiods causing excesswear and tear. Attention toenergy efficiency detailscan mitigate some dura-bility problems, includingthose from moisture andunwanted air infiltration.
• Environmental Performance– While quantifying thevalue of the environmentalbenefits of energy effi-ciency upgrades is oftendifficult, the qualitativevalues are readily appar-ent. Benefits such as re-duced energy useultimately result in less airpollution and a slower rateof natural resources deple-tion. Some efficiencyproducts use recycledmaterials, such as celluloseinsulation. Many new air-conditioning systems use arefrigerant that is notharmful to the ozone layer.In addition, the systemsapproach to efficiency,comfort, and durability canmake the existing spacesufficiently comfortableand durable to extend thelife of the home itself.
BENEFITS TO HOME REMODELING PROJECTS THATINCLUDE ENERGY EFFICIENCY STRATEGIES
• Affordability – Energyefficiency upgrades haveoften been evaluated inrelation to the monthly costof ownership. Light bulbsare a good example wherethe highly efficient fluores-cent bulbs are comparedto the higher energy andreplacement costs ofincandescent bulbs, result-ing in a relatively shortpayback period. Althoughthe cost of energy effi-ciency upgrades raises thetotal remodeling projectcost, monthly utility savingsare measurable and con-tinue throughout the life ofthe home – eventuallyresulting in a payback onthe initial investment.Although some remodelingelements could be aguedas a recouped investmentwhen one considers theresale market value of thehome e.g. kitchen and bathupgrades, most remodelingprojects do not recouptheir total investment. Inaddition, most new prod-ucts used in the remodelingwill age and depreciate.Improving energy effi-ciency is the one remodel-ing element that as aninvestment will have acontinued annual returnregardless of the resalemarket value.
5
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
5Although any one strategy toenhance the energy effi-ciency of the home may beperformed independently ofthe others, this case studycombines many differentstrategies into a system thatworks together to achieve thegoal of at least 30% energysavings. The strategy listevaluates each EE feature,comparing the “typical”approach with the “SEER”approach, to enhance theenergy performance of thehome. The overall energyefficiency features that wereconsidered in the case studyinclude:
• Insulation• Windows and doors• Air sealing• Heating and cooling
equipment• Water heating system• Lighting and Appliances• Additions• Renewable energy systems
Each feature has within it,strategies to achieve thegoals of reduced energyconsumption, increasedcomfort and durability, and ifpossible, energy productionfrom renewable sources. Anexamination of specificstrategies shows the effective-ness of incorporating thesestrategies into a remodelingproject.
5.1 WALL INSULATIONSYSTEMThe home originally had noinsulation in the walls. Framedwith full 2x4 construction, thewood siding on the outsideand interior 1x6 sheathingprovided the wall structure
STRATEGIES FOR ENERGY EFFICIENCY INREMODELING
that stood for more than 100years. Since the home wasunoccupied for almost 10years, a prime goal was toremove the deterioratedsiding and replace withsheathing and house-wrap toprotect the home’s interiorduring construction. Thiseffectively left the exteriorwall system with coverings onboth sides of the framing. Thiscondition made use of battinsulation materials nearlyimpossible. In addition, theirregular framing dimensions,including depth, meant thatbatt products would have anirregular fit.4
Based on the existing wallconditions, two wall cavityinsulation choices becameclear – the use of blowninsulation materials such asfiberglass, cellulose androckwool, or use of a foam-in-place insulation. Blown orfoamed insulation materialsprovide more of an opportu-nity to completely fill irregularwall cavities and may beinstalled through small open-ings in the framing bay. Theblown or foamed insulationproducts are particularlyadaptable to insulating wallsections that have coveringson both the exterior andinterior of the framing mem-bers.
Additional insulation on theexterior of the framing wasalso considered since thesiding was being replaced. Inolder homes, the framingmaterial accounts for more ofthe wall area than newhomes today, so use of anexterior insulation can add alarge benefit to the overall R-value of the wall system.
Typical products includesheet foam board of variousthicknesses. However, anotherapproach is to use productsthat combines the sidingmaterials with the insulation.
5.1.1 WALL INSULATION –SEER CASE STUDY
The approach taken in theSEER case study was basedon the wall conditions thatwere:
• Covered on both theinterior and exterior of theframing,
• Constructed of rough cut,irregular framing members,
• Typical of large framing-to-cavity ratio, i.e. largeamounts of framing.
Based on the wall structuralassessment, the following wallinsulation options wereselected:
Use blown or foamedinsulation in the wallcavities.Use sheet insulation underthe siding.
The two most commonoptions for insulating existingwall cavities with coveringson both the exterior andinterior of the framing arespray foam and blown fibrousinsulations such as fiberglassand mineral wool or blownloose-fill insulation such ascellulose5. Blown cellulose wasselected for this case studybased on:
The much higher installedcost of foamed-in-placeinsulation6.
4 However, the irregular fit could be overcomewith careful attention to batt installation details.5 Other blown insulation materials are manufac-tured but much less common and available.6 Based on estimates received by the remodeler.
6
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
7 Cost data primarily from RSMeans, 2004 with‘Location Factors’ applied.8 All R-value units in °F·hr·ft2/Btu.9 The insulated vinyl siding CraneBoard, ismanufactured by Crane Performance Siding.
Insulation blown into wall cavities
The capability of dense-pack cellulose to signifi-cantly decrease infiltrationloses,The availability of contrac-tors and equipment toinstall blown insulation, andThe ready availability of thematerial.
The estimated installationcosts7 for blown celluloseinsulation is approximately$0.43/sf with an additional$1.74/sf to drill holes for blow-ing access. The total installedcosts then for installed blowncellulose insulation is about$2.17/sf of insulated wall area.Further, the estimated in-stalled cost of the wall insula-tion of the case study house
with 1338 sf of retrofittedinsulated wall area is $2,900.
In addition to the insulation inthe wall cavity, insulatedsheathing was selected forapplication to the exterior ofthe framing. This is advanta-geous since in many older
Blown cellulose insulation
homes large portions of thewall are wood membersproviding an R-value8 ofabout 4. Compared with theinsulated cavity of aboutR-14, this represents a largeportion of the wall with anR-value of only about one-
third of the cavity. To mitigatesome of these framing ef-fects, rigid insulation is usedunder the siding. Two choicesare available; board insula-tion applied over the framing(or existing wood sheathing)or insulated siding. In the casestudy, insulated vinyl sidingwas selected.
Features of the insulated vinylsiding9 include a coverage of19" vertical per horizontal run(standard vinyl at 7.5" to 10")and an insulated core ofexpanded polystyrene. The R-value as a tested system fromthe manufacturer data is R-4.A comparison of the cost ofinstalling insulated vinyl sidingwith standard vinyl siding overa rigid foam board is shownin Table 1.
7
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
Insulated siding trim
Insulated siding
Based on the cost estimatesand primarily the labor sav-ings with a larger coveragearea, there is virtually nodifference between theinstalled costs of each system.The cost of installing theboard insulation to provide athermal break for the framingadds approximately $970 butwith the selection of theinsulated vinyl siding, theadditional cost is about $900.
Table 1 – Insulated Siding Cost Comparison
All values are normalized to a 100 square foot basis.Cost estimates based on interviews or cost estimate tables.
Cost of standard 9" or 10" siding $60
Labor to install $81
¾” foam sheathing (~ R4) $26
Labor to install sheathing $22
Total for vinyl siding over R4 rigid insulation $189 per 100 sf.
Cost of integrated insulated siding (R4) $132
Labor to install (40% faster) $49
Total for R4 integrated siding $181 per 100 sf.
8
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
5.2 CEILINGINSULATION SYSTEMAs with the wall system, therewas no insulation in theceiling or attic of the existinghome. Similar choices ofinsulating materials is avail-able for the ceiling or atticspace, with blown, foamed orbatt insulation products beingapplicable and easily in-stalled.
Blown or foamed insulationproducts are often used inceiling spaces following theinstallation of the ceilingcovering. These products canbe installed to various thick-nesses depending on thelevel of insulation required.The blown insulation productscan also be installed over anyexisting insulation.
Cathedral ceilings howeverpose more challenge to theblown insulation productssince netting would benecessary to hold the insula-tion between the rafters. If theceiling covering is in place, asimilar installation method asexisting walls can be used.Foam insulation products canbe used easily in the rafterspace since it can be applieddirectly to the underside ofthe sheathing and in variousthicknesses.
An important issue to consideris the air space between theinsulation and the sheathing.An air space under thesheathing is often requiredper the building code an/orshingle manufacturers. Ifvented soffit is used, the roofventilation should extend tothe ridge vent. In any case,sealing of air leakage into theattic (or rafter space if insu-lated), should be provided.
5.2.1 CEILING INSULATION– SEER CASE STUDY
Since the walls are beingblown with cellulose insula-tion, the same material wasselected for the ceiling of theexisting home. Based on theinstallation of a nominal R-19in the exposed attic floor, thecost for installing fiberglassbatt insulation and cellulose isvirtually identical. Otherbenefits as air sealing favorthe installation of blowncellulose insulation over battproducts in some locations.The estimated cost for install-ing blown cellulose insulationin the existing home ceiling isapproximately $0.62/sf for anR-19 coverage (comparedwith $0.67/sf for batt insula-tion). The cost for insulatingthe 560 sf existing ceiling withfiberglass batts is about $375.
For the case study however,the recommended R-valuefor the ceiling in this coldclimate is R-38. Based on costestimates, the cost of install-ing cellulose insulation in thecase study ceiling is about$672. The additional cost forthe case study home isapproximately $297 to in-crease the ceiling insulationto R-38 over R-19.
5.3 BASEMENT ORFLOOR INSULATIONSYSTEMMany remodeling projectsinvolve basement or crawlspaces that were originallyuninsulated, as is true for thiscase study. Though con-structed with a basement, thefoundation space was andwill continue to be uncondi-tioned. Isolating the uncondi-tioned basement space fromthe conditioned house wasachieved simply by insulatingthe floor joist space. The mostcommon insulation methodfor the floor joist space is battinsulation, using unfacedbatts. However, this is also anexcellent location for sprayapplied foam insulationproducts, especially thosewith a low permeability.
Floor insulation between joists
9
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
For unconditioned basementsand some crawl spaces,addition of wall insulationover the above-grade sectionof walls can help to temperthe basement temperature.Rigid foam insulation at-tached by vertical gluebeads is a simple method ofinstalling the foam board.Check with local buildingcodes for any requirementsfor installing foam in uncondi-tioned basements andcrawlspaces.
5.3.1 BASEMENT ORFLOOR INSULATION – SEERCASE STUDY
For the case study home,where the basement is poten-tially subject to regular dampconditions, the floor waschosen for insulation ratherthan the basement walls. Thefloor insulation options includeblown or foamed insulationand batt insulation. In thislocation, use of batt insulationis preferable due to thehigher cost of installing blownor foamed insulation prod-ucts. The typical insulationlevel required for this locationwould be at least R-19. Use ofR-30 is preferable if the floorjoists are nominal 2x10’s as isthe case with the case studyhouse. The additional cost ofupgrading the floor insulationfrom the minimum R-19 to R-30 is approximately $328.
5.4 WINDOWS ANDDOORSThe use of energy efficientwindows and doors in theremodeling effort is verysimilar to that of new homes –
with the primary limitation totheir use being simply theknowledge of availableproducts. Information con-cerning appropriate windowsfor a given climate is easilyavailable on the Internet andthrough window manufactur-ers. Use of low-e coatings, anenergy benefit in most allclimates, is commonplace forwindow glass yet must still bespecifically requested inmany locations, as is theaddition of an inert gas forthe space between thepanes. Both the low-e andgas fill options for windows willsignificantly increase theefficiency of the windowwhile increasing the comfortof the room.
Similarly, doors have a rangeof energy efficiency perfor-mance, but the energyefficiency ratings are moredifficult to identify directly onthe product. A minimalamount of research will
identify doors with a betterinsulating value than another.Foam-core doors with littleglazing will have the bestenergy performance.
5.4.1 WINDOWS ANDDOORS – SEER CASESTUDY
The additional cost of select-ing energy efficiency featuresfor the windows varies signifi-cantly between manufactur-ers. Generally, the added costof low-E coatings and gas fillranges from a low of a fewdollars per window to nearly$100. But many manufacturersoffer an energy efficientoption that includes low-Ecoatings or a combination oflow-E coatings and gas fill, fortheir windows at a cost ofabout $2/sf of window area.For the case study house with196 sf of windows then, theadditional cost for energyefficient windows is about$400.
Energy efficiency windows and door in cottage
10
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
5.5 AIR SEALINGAir sealing to prevent energylosses due to infiltration is animportant part of the overallenergy performance of thehome, new or remodeled.Though this strategy is notspecifically addressed incurrent building codes,significant improvement inenergy savings and comfortcan be achieved throughsimple and inexpensivetechniques. Any place whereair can leak from inside theconditioned area to otherareas, including uncondi-tioned basements,crawlspaces, attics, garages,etc. are points where energyis lost to the outdoors. Airsealing can be done when-ever any part of the home isbeing remodeled, or on itsown, to simply increase theefficiency and comfort of thehome.
Many options are available tothe remodeler when airsealing homes. Foams, insula-tions, caulks, gaskets, andsheet goods are all productssuitable for achieving thegoal of lowering infiltrationlosses in the home. Ideally,multiple strategies should beimplemented during theconstruction phase. This willbetter ensure adequatesealing is achieved.
In choosing methods for thecase study, preference wasgiven to inexpensive solutionsthat could be executedduring multiple phases of theremodeling process. A pri-mary concern to the teamwas to reduce the migrationof moisture-laden air from the
foundation areas and out-doors into the thermal en-velop.
5.5.1 AIR SEALING – SEERCASE STUDY
For this “gut” remodel project,the air sealing effort is fairlyextensive. Since the housewas framed nearly 100 yearsago, there are ample oppor-tunities to fill gaps and holeswhere the:
• Framing adjoins block orstone,
• Top plate and ceiling joistsintersect,
• Window and door roughopenings are framed andirregular,
• Wires and pipes passthrough to the attic, base-ment, and walls,
• Interior stairway exists to thebasement
Several trades were utilizedduring the remodeling phases
to achieve sealing of thebuilding. These included aprofessional air sealing con-sultant, the insulation contrac-tor, the drywall contractorand the remodeler’s owncrew. Techniques utilized forthe project were:
Exterior plywood sheathingwas glued to framingWindow frames werecaulked to the framingWallboard was glued toframingSill seam and band joistareas were foamedFloor and wall penetrations(inc. at stairway) werefoamed
Though the choice of insula-tion was primarily made forother reasons, dense packedinsulation will also aid incontrolling infiltration byreducing airflow within wallcavities. If air-sealing strate-gies had been ignored duringthe gut-rehab it is estimated
Air sealing around windows
11
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
that an additional 60% ofheating and cooling energywould have been required tooperate the home10.
An expeditious method todetail all of the air sealingopportunities in existinghomes is to obtain the ser-vices of specialized contrac-tor. Costs for such servicesvary depending on the sizeand complexity of theproject. Many times special-ized energy contractors offertesting and guarantees ofperformance with their air-sealing service. For manyremodeling projects, air-sealing costs will be low sincethere will be little addedlabor and materials if tech-niques are performed duringthe construction process withthe same work crews. In thisgut-rehab the insulationcontractor charged anadditional $500 to performthis work.
Air barrier on outside of house
5.6 HEATING ANDCOOLING EQUIPMENTThough complicated in theirdesign, the equipment toheat and cool the home canbe installed with attention toa few basic principles:
• Install a highly efficientcooling and heating sys-tem, maximizing efficiencywith installation and opera-tion costs.
• Place all ducts and equip-ment in conditioned space.
• Size the equipment perACCA Manual J or otherrecognized sizing tool, useACCA manual D to deter-mine duct sizing.
• Seal ducts preferably withmastic or silver11 (not duct)tape.
• Install passive returns whereducted returns are non-existent or impractical.
The type of heating andcooling equipment, its effi-
10 Based on the reduction of infiltration losses from1.0 ACH to 0.25 ACH with ventilation added.11 Typically listed UL 181 tape.
ciency and its location aremost often at the recommen-dation of the installer. How-ever, various types oftechnology can be consid-ered as part of the evaluationof energy efficient heatingand cooling equipment:
• Condensing over atmo-spheric furnace tech-nology,
• SEER ratings of greater than10 for air-conditioningequipment,
• HSPF ratings of greater than7.0 for heat pump units,
• Ground-source heat pumptechnology,
• Active solar heating tech-nologies, and
• Combined hot water/heating technologies.
The installation of the HVACsystem including ducts orpipes is as important as theequipment itself. Attention tothe entire process fromequipment selection toinstallation, to controls willshow benefits long after theremodeling project is com-plete.
5.6.1 HEATING ANDCOOLING EQUIPMENT –SEER CASE STUDY
In the case study home, theplan had called for a SEER-10air conditioner compressorwith an AFUE-80 propanefurnace located in the base-ment. High electric prices($0.11-0.15/ kWh) and asignificant heating seasoneliminated the option of anair-to-air heat pump system,natural gas was not available
12
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
on the property, and thebuilder desired not to useheating oil.
Since the site had a highwater table, a ground sourceheat pump was investigated.After some consultations withseveral manufacturers, instal-lation contractors, and en-ergy modeling, this systemwas chosen for its low annualoperational costs. The largelot enabled a cost effectivehorizontal closed loop con-figuration which wastrenched and installed byremodeler (with HVAC con-tractor) and serves a total ofthree packaged units for thetwo homes on the site. Thetwo-ton compressor and airhandler unit in the studyhome, as well as all supplyand return ducts are locatedwithin conditioned spacewhich dramatically reducessystem loses throughout theyear. In addition to this, allductwork was rigid metal and
Ground source heat pump in conditioned space
All duct joints sealed
mastic was installed on allduct connections. Theseimprovements to efficiencyof the distribution systemallowed the unit to bedownsized by one-half a ton.
Even though the originaldesign recommendedducted returns on both levels,the builder chose to installpassive wall returns betweenall bedrooms and the openstairway where the centralreturn was located.
The original estimate to heatand air condition the buildingusing a single 3-ton SEER-10system and AFUE 80% pro-pane furnace was $9,100 forall labor, equipment, andductwork. The cost to installthe 2-ton geothermal systemwas $12,300 including alllabor, equipment, ductwork,and ground piping. An addi-tional cost estimate of $600would have been expectedfor the ground excavationwork but in this case wasperformed by the remodeler.
13
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
5.7 WATER HEATINGSYSTEMThe energy efficiency waterheating system in the SEERcase study involves allaspects of water heatingfrom cold water inlet to thehot water outlets andincludes pre-heat systems,primary water heating equip-ment, and piping to theoutlets. The primary goal of anefficient water heating systemis to reduce energy losses inthe water heating equipmentand in the piping. To achievethis goal, a demand waterheater and parallel pipingsystems are considered to bethe best option in this climate.Other systems that wouldinclude for example a heatpump water heater or distrib-uted water heaters at eachoutlet would increase effi-ciency even more but atprohibitive costs at this time.
Demand water heaters, eitherfuel fired or electric arelimited by the input energythat in turn limits the maxi-mum temperature rise thatcan be achieved at a givenflow rate. Tank water heatersdo not suffer from this limita-tion since the volume ofstored water can be suppliedto the outlet at (theoretically)any flow rate. Tanks howevercannot supply heated waterbeyond the capacity of thetank and the outlet tempera-ture of the water will de-crease as it mixes with theincoming cold water. Also,tanks have a limited amountof input energy so that therecovery to bring the tankback to full temperature isover many minutes. In addi-tion, tank storage of hot
manifold is used for thispurpose.
The system design in this casestudy uses an electric de-mand water heater feeding aparallel piping system. Electricdemand heaters are typicallylimited to lower temperaturerises at typical flow rates inhomes, so to both decreasethe necessary size of thedemand water heater whileproviding adequate hotwater delivery, a pre-heatsystem can be used. Thechoice of demand heater isimportant when using thisstrategy, however, since notall products will properlyaccount for variable inputtemperatures.
There are a number ofchoices to preheat the coldwater prior to the demandwater heating equipmentincluding:
• Desuperheater from theground-source heat pump,
• Solar thermal, or• Waste heat from the drain.
Manifold plumbing system
water will lose energy to thesurroundings, so that periodi-cally, the water will need tobe reheated even if no wateris used. If a demand heatercan supply the anticipatedhot water needs, it is almostalways more efficient thantank storage heaters.
The hot water piping is an-other part of the overallwater heating system thatcan be designed to reducewasted energy by supplyinghot water outlets with as smalla diameter pipe as possiblewhile maintaining the desiredflow rate. This design results ina lesser volume of water inthe pipe to the outlet with lessenergy wasted as the pipecools to ambient tempera-ture. Smaller diameter pipeshowever can not flow largequantities of water so thepiping system is designed as aparallel system so that onlyone outlet is supplied from adedicated piping run fromthe water heater. A hot water
14
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
Among the options, the mostconsistent source throughoutthe year, in this area, is thesolar system, specifically, anactive solar thermal systemthat charges a pre-heat tank.
The entire hot water system,taken together, can providehot water to the outlets withfewer losses, and with perfor-mance similar to that ofmuch larger tank systems.
5.7.1 WATER HEATINGSYSTEM – SEER CASESTUDY
As with other systems in thehome, the water distributionand heating systems requiredreplacement. An estimate of$2,700 was obtained for thesupply and installation ofcopper supply lines for thehot and cold water in thehome. In comparison, a priceof $2,200 was secured tosupply and install a singlecentral manifold and PEXpiping for all the supply linesin the home. This savings wasprimarily due to the reducedlabor costs associated withrunning the flexible supplylines since the materials costswere very similar.
The original design for thewater heating system was toinclude a “typical” propane-fired storage tank with anenergy factor of approxi-mately 0.56 located in thebasement. While this wouldhave been a relatively inex-pensive option to purchaseand install, the performanceof this equipment, and ex-pected standby loses due toit’s location in unconditionedspace, would have costsignificantly more to operateover it lifetime. The choice of
a solar preheated tank andtankless demand heaterlimited the storage tank lossesto energy generated only bythe solar system. The solarcontribution is expected torepresent approximately 57%of the annual hot water load.The estimate for the cost of
the supply and installation ofthe solar preheat system withtankless backup heater is$4,400. This, of course, issignificantly more than the$500 – $700 cost to install astandard residential electricor propane tank.
Hot water system in cottage
Solar thermal collector with PV panel for pump
15
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
5.8 LIGHTS ANDAPPLIANCESEven energy efficient homesutilize many electrical devicesthat add to the energyconsumption ‘bottom line’.Minimizing energy use is left tothe consumer who mustdecide on individual appli-ances and select energyefficient options. Two mainareas where this is easily doneare larger appliances, such asrefrigerators and washingmachines, and lighting.
Efficient appliances are easilyidentified under the federalgovernment’s EnergyStar®
program. The EnergyStar®
marked appliances havebeen tested to be the mostefficient appliances available.Likewise, lighting providesanother opportunity to ex-tract large energy savings.Use of fluorescent fixtures orlamps are the best optiontoday to save lighting energy.Newer technologies such asLED lighting are not yet widelyavailable for general use inthe home but show promisefor even more savings thanfluorescent.
5.8.1 LIGHTS ANDAPPLIANCES – SEER CASESTUDY
The remodeler for this homemade a bulk purchase ofcompact fluorescent replace-ment light bulbs that he willuse in all the light fixtures ofthe home. Since he tookadvantage of special pricingon these units his estimatedcost increase over incandes-cent bulbs is approximately$12.00 for all the fixtures in the
home. The appliances for thehome are being chosen withan eye toward efficiency. Therefrigerator, dishwasher, andclothes washer will all beEnergyStar® rated. The esti-mated additional cost toprovide these EnergyStar®
rated appliances is $320.
5.9 ROOM ADDITIONSA remodel project involving acomplete addition is anexcellent opportunity toinclude energy efficiency‘from the ground-up’. Wall,roof and foundation construc-tion can be performed usingnew-construction methodsthat provide energy upgradesfrom normal practices. Manyof these upgrades can beemployed with little extra costsince the main work wasalready being performed.Also, some energy upgradescan actually result in con-tained costs – for examplewith the heating and coolingsystem. An efficient addition
may be able to be servicedfrom the existing HVAC systemwhere a standard, less effi-cient addition might haverequired a separate heatingand cooling system for theaddition.
Many of these issues alsopertain to room conversions,for example an attic orbasement space. Use of moreefficient methods and tech-nologies can result in a morecomfortable space, at a nearequal cost but with lowermonthly bills.
5.9.1 ROOM ADDITIONS –SEER CASE STUDY
The addition is made frompre-manufactured structuralEPS foam and steel tubepanels and therefore doesnot require any additionalstructural supports. The floor ofthis addition is made ofconventional solid woodenjoists and plywood decking.The original design called fora conventionally framed
Addition construction using foam panels
16
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
Addition constructed in 6 hours
Ridge and eave supports for roof panels
addition with a vented attic.The choice to use structuralpanels allowed for the cre-ation of a cathedral ceiling inthe room and dramaticallydecreased the close-in timefor the project. Once theconventional wooden deckhad been built, it took theremodeler’s crew of three,plus two support techniciansfrom the panel manufacturer
only 5 hours to construct thestructure.
Mr. Asdal estimated that toconstruct this addition usingconventional framing (2x4walls) would have cost him$3,000. The costs for thestructural foam panel addi-tion were $5,700. While hesaw the speed of the con-struction being an advantage
in some situations, in this casehe thought the problems hehad with scheduling the jobwith the supplier’s crewcountered any savings hehad in the speed of construc-tion.
5.10 RENEWABLEENERGY SYSTEMSLast but not least are thoseopportunities in the remodel-ing project to include renew-able energy systems that canprovide a portion of thehome’s energy needs. Thesesystems tend to be morecostly and require larger roofor ground areas, but alsoprovide large amounts ofenergy that is, in its operation,pollution and waste free. Themost prominent systems aresolar photovoltaics thatconvert sunlight to electricityand wind generators thatconvert wind energy toelectricity.
Solar thermal systems for hotwater, briefly describedabove, are most often usedto raise the efficiency of thehot water or heating system.Passive solar systems, such assunrooms, or trombe walls,also use solar energy toreduce the heating loads inthe house.
Use of renewable energysystems not only reduce theconsumption from non-renewable utility energysupplies, but provides a bufferagainst fluctuating costs ofenergy. When a renewableenergy system is purchasedand installed, a portion of thecost is considered as the‘fuel’ purchase. Unlike engine
17
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
PV system on cottage home
Ridge beam for roof supportR-50 roof and R-30 wall panels
generators for example, thatcan provide an alternative toutility energy supply, theengine systems still requireregular purchase of fuel suchas diesel or gasoline – thatcan change in price, some-times dramatically andquickly.
Renewable energy systemstypically have required theservices of a solar systemdesigner and installer, andspecial attention to utilityinterconnections andmetering.
5.10.1 RENEWABLEENERGY SYSTEMS – SEERCASE STUDY
An onsite photovoltaic (PV)solar system was investigatedfor the site. Since there wasno significant shading, goodroof orientation, and ampleroof area, the home wasdeemed suitable for a PVarray. The major factors thatled to the decision to pur-chase a system were thesignificant financial incentivesavailable and the simplifiedutility interconnection proce-
Aerial view of PV system
dures. There isa statewideresidentialgrant pro-gram inplace andoperated bythe Board ofPublic Utilitiesthrough theNew JerseyClean EnergyProgram(NJCEP).Through thisprogram, thesolar installerwill receive an incentiveworth up to $5.50 per ratedDC Watt of solar equipmentthat allows him or her to offera substantially lower price tothe homeowner for theinstalled system. This dealer isalso handling the rebateapplication process and inturn, finances the rebateamount for the homeowner.
A 3.0 kW mono-crystallinesystem is located directly onthe Cottage roof with a 4.2kW system located on thegarage roof also feeding intothe building’s utility service.
18
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
The power conditioninginverters are located insideboth in the garage andbasement of the home. Theout of pocket expenses forthe homeowner are approxi-mately $15,120. The NJCEPrebate paid for 70% of thesystem or $35,280. The systemis expected to produceapproximately 9,000 kWh peryear.
Garage PV system for cottage home
PV system inverters
19
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
A summary of the energyefficiency feature costs isdescribed in the followingtable. The costs have beenderived from a combinationof construction cost estimates,actual bids from trade con-tractors and from theremodeler. The added costs(or savings) for the energyefficiency feature as de-scribed in the “Net” columnrepresent a best estimate atadding the desired energyefficiency improvement in thishome over standard practice.
6SUMMARY OF COST AND SAVINGS ESTIMATES
Adding the energy featuresto the existing home (BaseRetrofit) costs approximately$23,000 over leaving thehome “as-is” and performingonly basic renovations tomaintain the home butincluding new appliances aspart of the energy features.With the SEER project, addi-tional upgrades to the energyefficiency features are in-cluded to significantly de-crease the energy used in the
home. These additionalfeatures represent an addi-tional cost of about $14,000or 60% more.
In conjunction with the addi-tional energy efficiencyfeatures a solar electric(photovoltaic) system is alsoincluded. The system’s fullprice is about $50,000 butwithin the NJ Clean EnergyProgram will cost the home-owner about $15,000. Conse-quently, the total cost for the
Table 2 – Energy Efficiency Cost Summary
Technology Base Retrofit SEER Retrofit Net Cost or Savings
Wall Insulation–Cavity $1,4561 $2,900 $1,444
Wall Insulation–Continuous $2,8482 $3,656 $808(w/ Siding)
Ceiling Insulation $375 $672 $297
Floor Insulation $470 $798 $328
Windows $2,420 $2,820 $400
Air Sealing $0 $500 $500
HVAC System $9,100 $12,900 $3,800(inc. $600 for excavation)
Water Heating System $700 $4,400 $3,700
Water Distribution System $2,700 $2,200 $-500
Lighting (bulbs only) $11 $23 $12
Fixed Appliances $1,630 $1,950 $320
Addition Framing and $3,000 $5,700 $2,700Insulation
Solar Electric System (PV) $0 $15,120 $15,120
Total with PV3 $23,080 $52,009 $28,929
Total without PV3 $23,080 $36,889 $13,809
1 Includes $733 for sheathing removal and disposal and $723 for R-13 batt insulation.2 Costs for uninsulated vinyl siding were used here to provide an accurate comparison.3 Without added cost for new minimum-efficiency appliances.
20
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
12 The actual benefit is a net-gain to the utility, butthe economic value of the net-electricity fedback to the utility is not recoverable at this time.
SEER energy efficiency fea-tures and including a PVsystem, is about $54,000. Forthis cost, the home is ex-pected to achieve a zeroenergy utility bill on an annualbasis.
Based on energy simulations,estimates of energy use andsavings for the SEER CaseStudy house have beendeveloped and are summa-rized in Table 3.For the base home remodel,the estimated energy costs(w/o service charges) showan annual energy savings ofabout $500 over the existing(before) home, including theadded energy cost for cen-tral air-conditioning. CentralA/C would only be feasiblegiven the minimal energyfeatures included in the baseretrofit. Had central A/C notbeen included, the annualsavings would have beenabout $665.
When considering the addedcosts for the energy features,including a new furnace andduct system and a newaddition to replace thedeteriorated existing addition,but not including replace-ment of the appliances, thetotal cost is estimated at$23,080. Evaluating the addedcosts for the energy featuresonly in terms of energy sav-ings reveals a lengthy 46-yearsimple payback. However, thisnarrow approach ignores theadded longevity of the homeand the significant increase incomfort and durability basedeven on the modest energyefficiency upgrades.
However, when looking at theincrease in the energy perfor-mance of the home from the
SEER energy efficiency ap-proach, a much differentpicture emerges. Ignoring thesolar electric (PV) system forthe moment, the value of theenergy savings for the SEERenergy retrofit is about $2,800over the existing home’senergy costs, and about$2,300 from the base caseretrofit. This dramatic improve-ment results from an inte-grated (systems) designutilizing energy efficiencytechnologies that are se-lected based on the particu-lar site characteristics and aknowledgeable remodelerand trades contractor. Evenwith the increased costs of60% over the base energyefficiency retrofit, the simplepayback approaches 13years for the existing homeand about 6 years over thebase case.
When adding the PV systeminto the economic valuationof the SEER retrofit case, theresulting electricity costs go tozero12. The simple paybackthen is about 14 years fromthe existing home, and 9years from the base case. Thisapproach values the PVsystem solely for its energybenefit while adding no valuefor the reduction in pollution,security from rising energycosts, and reduced demandfor fossil fuels.
Other economic valuationsare possible. When consider-ing a loan of about $52,000 topay for the full SEER energyefficiency remodel includingthe PV system, an interestrate of 6% over 30 yearswould show a monthly break-even cost based on theenergy savings. And this
assumes that the energy costsremain fixed over the term.
Still yet another approach isto consider the return oninvestment (ROI) of thesavings when investing asimilar amount as the energyefficiency upgrades. In thiscase the ROI is over 7% whencomparing the upgradesfrom the existing home, andover 11% when consideringthe upgrades from the basecase remodel. Again, this ROIassumes fixed utility rates overthe useable lifetime of theenergy efficiency systems.A summary of the economicanalysis is shown below.
21
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
Table 3 – Summary of SEER Case Study Energy Use1 and Costs/Savings
Performance Before Base Base SEER SEER SEERCharacteristic Retrofit Retrofit Savings Energy Savings Savings
Over Efficient Over OverBefore Retrofit Base Before
Heating Peak Load 65,400 45,400 31% 15,900 65% 76%(Btuh)
Cooling Peak Load 0 26,400 — 13,400 49% —(Btuh)
Annual Heating Load 134.3 71.0 47% 24.3 66% 82%Annual Cooling Load 0.0 12.7 — 10.9 14% —Totals (Million Btu) 134.3 83.8 38% 33.2 60% 75%
Heating Cost2 $2,660 $1,794 33% $179 90% 93%Cooling Cost $0.0 $163 — $61 — —
Total Heating and $2,660 $1,957 26% $240 88% 91%Cooling Costs
Water Heating Use 30.5 27.4 10% 5.6 80% 82%(Million Btu)Appliance/Lighting 19.6 19.6 0% 13.3 32% 32%Use (Million Btu)
Water Heating Cost- $364/O $556/P -53% $193/E 65% 47%Oil/Propane/Elect
Appliances/Plug Loads $672 $682 -1% $455 33% 32%
Estimated Annual $3,696 $3,195 $888Energy Costs
Solar PV System (kWh) 0 0 8,899Value of kWh @ utility — — —rates ($) $0 $0 $1,043
Total Estimated Annual $3,756 $3,304 13.7% $-95($0)4 103% 103%Energy Costs3
HERS Score 39.3 77.6 49% 93.1
Notes:1 Energy Use Estimates based on simulation software2 Electricity Rates: Applies to Before, Base and SEER energy estimates
Monthly Service Charge = $5.00Jun-Sep, 0-600 kWh @ $0.1246/kWh
> 600 kWh @ $0.1508/kWhOct-May, 0-1000 kWh @ $0.1134/kWh
> 1000 kWh @ $0.1107/kWhPropane Rates: Applies to Base energy estimates for heating and water heating
Monthly Service Charge = $4.00/monthJan-Dec, @ $1.85/gallon
Fuel Oil Rates: Applies to Before energy estimates for heating and water heatingMonthly Service Charge = $0.00/monthJan-Dec, @ $1.69/gallon
3 Including service charges and PV net-savings.4 Currently, there is no payment required by the utility for annual net-production.
22
S E
E R
2 0
0 3
C
A S
E S
T U D
Y R
E P
O R
T
Summary of Economic Analysis Based on Energy Value Only
Cost to add Base energy efficiency features to the Existing home remodel $23,080
Annual Energy Savings (including the addition of A/C) $501
Annual Energy Savings (with out the addition of A/C) $664
From existing-to-Base (w/ A/C) Retrofit - Simple payback 46 years
From existing-to-Base (w/o A/C) Retrofit - Simple payback 35 years
Return-On-Investment (w/ A/C) 2.2%
Return-On-Investment (w/o A/C) 2.9%
Cost to add SEER energy efficiency features to the Existing home remodel(w/o PV) $36,889
Annual Energy Savings $2,808
From Existing-to-SEER Retrofit – Simple payback 13 years
Return-On-Investment 7.6%
Cost to add SEER features to the Base home remodel (w/o PV) $13,809
Annual Energy Savings $2,307
From Base-to-SEER Retrofit - Simple payback 6 years
Return-On-Investment 16.7%
Cost to add SEER energy efficiency features to the Existing home remodel(w/ PV) $52,009
Annual Energy Savings $3,696
From Existing-to-SEER Retrofit – Simple payback 14 years
Return-On-Investment 7.1%
Cost to add SEER features to the Base home remodel (w/ PV) $28,929
Annual Energy Savings $3,195
From Base-to-SEER Retrofit - Simple payback 9 years
Return-On-Investment 11.0%
Loan Payment – SEER and PV system (7%, 15 years, $28,929) $260.02
Monthly utility savings ($3,195 annual cost) $266.25
23
S E E R 2 0 0 3 C A
S E S T U D
Y R E P O R T
Adapted from comments ofthe builder/remodeler, BillAsdal
The first SEER remodel site is ina rural setting. It is very typicalof many of the housesthroughout the countrysidenot only here, but near andafar. The average age ofhousing in the country is 32 or33 years. This one is 100+.Regionally, these averagescan be as high as 55 or 60.And in the not too distantPennsylvania and the AmishCountry it gets up there 60 –70 years, so there is a verylarge identifiable housingstock that is deficient in itsenergy efficiency and itsmechanical systems. But quitefrankly, houses of this vintagein fact have very contempo-rary square footage anddesign attributes. For ex-ample, this one though it wasbuilt between 1898 and 1903,at about 100 years old, has10-foot ceilings on the firstfloor and 9-foot ceilings onthe second floor. There aretwo homes on the site. One ofwhich is very close to 4,000 sq.ft. and the other, which we’recalling the cottage houseruns just shy of 1,500 sq. ft. Sothese are not unusual struc-tures, but in fact based ontheir age unlike the post warhomes of 1,100 or 1,200 sq. ft.have the square footage thatcontemporary buyers arelooking for and are verymuch serviceable for another100 years if kept dry. I thinkthese attributes in addition tothe fact that we are com-pletely gut rehabbing bothhouses, give us a goodopportunity to be proactiveand say that these housesshould not be abandoned.
As an aside, the state of NewJersey led the country inintroducing the rehab codein 1998, recognizing thatneglected urban, maturesuburban, and the old ruralhomes were 3 categorieswherein you could find alarge housing stock that notonly need code upgradesbut are perfectly serviceable.In this project we find theopportunity to look at energyconservation and use ofrenewables as a primary partof the home remodelingproject. I think the combina-tion of property and physicalattributes lend itself well for a2003 SEER project setting.
The construction approvalprocess here as in many otherareas is much constrained inthe permitting of new homesso that there is a tremendousdemand on older homes tofill a need for new family orfor move-up buyers who incan’t get newly approvedlots or when these new lotssimply don’t exist. We’vegone from wetlands con-straints to planning constraintsto proximity to water con-straints with the result that ournew housing production isabout 40% of its high, whichwas achieved almost 15 yearsago. Again, there is lots ofpressure on these old build-ings to produce at today’sstandards and with a gutrehab I think we have achance to show how to dojust that. We have applied foran Energy Star rating on thelarger of the two homes andhope to do so on the cot-tage. For the larger home, we
have had an evaluation andthink that with a couple ofclever twists we will be ableto achieve an 86 score whichwill give us an Energy Starhome in the shell of a 100year old building. And that isvery very exciting to knowthat these old homes couldactually achieve that if youdo a gut rehab.
FIRST SEER REMODEL SITE - LEBANON, NEW JERSEY ADDENDUM
