ASHRAE Standard 90.1-2016 Code Change Review Summary

ASHRAE Standard 90.1-2016 Code Change Review SummaryDepartment of Energy (DOE) provides a qualitative and quantitative analysis of impacts of codechanges for every code development cycle. The qualitative analysis determines code changeaddenda applicable to prescriptive and performance code compliance methods that has directimpact on energy use. Furthermore, the qualitative analysis identifies which of the code changesresult in an increase or decrease in energy use. This section is summary of the qualitativeanalysis extracted from the Energy Savings Analysis report for ASHRAE Standard 90.1-2016(US DOE, 2017).Summary of code changes addenda included in ASHRAE Standard 90.1-2016 are provided inTable 2. This table summarizes the number of codes changes for each of the various sections ofthe code and the number of addenda items that directly impact building energy use.Table 1 Number of code changes addenda in ASHRAE Standard 90.1 - 2016SectionNumber ofAddenda5. Building Envelope6. Heating Ventilation and Air Conditioning7. Service Water Heating8. Power9. Lighting10. Other Equipment11. Appendices C and G12. Normative ReferencesVariousTotal1943421832912121Number ofAddenda withEnergy Impact9261111111051There are 121 code changes addenda included in ASHRAE Standard 90.1 – 2016. Of the 121code changes addenda, 51 addenda items were identified to have impacts on energy use. And 21out of the 51 addenda items were identified suitable for the quantitative analysis usingsimulations (US DOE, 2017). The code change addenda that has energy impacts are provided inTable 2. The 21 addenda items will be quantitatively analyzed to determine the ASHRAE 90.12016 code energy impact on the state of Florida.References:US DOE 2017. Energy Savings Analysis: ANSI/ASHRAE/IES Standard 90.1-2016. USDepartment of Energy. Office Energy Efficiency and Renewable Energy. Report. October es/documents/02222018 Standard 90.12016 Determination TSD.pdf. Accessed February, 2018.

Table 2 Commercial Code Change Summary for ASHRAE 90.1- 2016AddendumCodeSectionsAffectedCode Change Summary BetweenASHRAE 90.1-2013 and ASHRAE 90.1-2016Impact onEnergy UseIncluded inquantitativeAnalysisDiscussiona3.2, 5.1.2.1Modifies the definition of conditioned space andmodifies the heated space criteria tableDecreasesEnergy UseNoLowers the threshold for spaces to be consideredheated resulting in a requirement for additionalinsulation. Excluded from quantitative analysisbecause the prototype space classifications areheld constant from one edition of the standard tothe next.Increases stringency of hotel/motel guest roomcontrol.d6.3.2, 6.4.3.3DecreasesEnergy UseYese9.1.2Requires deeper thermostat setback for networkedguestrooms or those unoccupied for more than 16hours/day. Also requires ventilation to be turnedoff when guestrooms are unoccupied.Increases requirements for alterations to existingbuilding lighting systems.DecreasesEnergy UseNof9.4.1.1DecreasesEnergy UseNoi6.5.1DecreasesEnergy UseYesj6.5.3.3DecreasesEnergy UseYesRemoves the ventilation optimization exceptionfor ERV, making the requirement more stringent.l4.2.4, 4.2.5,5.2.1, 5.2.9(newsection)Changes an exception to the automatic daylightcontrol requirements for daylight areas underskylights from visible transmittance to effectiveaperture.Eliminates separate cooling capacity thresholdsfor requiring an economizer in computer rooms.Computer rooms will be required to follow thesame thresholds as comfort cooling applications.Requires variable air volume (VAV) systemventilation optimization even when energyrecovery ventilator (ERV) is installed.Adds verification requirements for envelopecomponents, including insulation, fenestration,doors, and air leakage.DecreasesEnergy UseNoExcluded from quantitative analysis because theanalysis does not take credit for verification orcommissioning.Excluded from quantitative analysis because theanalysis considers new construction only and thisapplies only to existing buildings.Changes an exception that increases stringency.Excluded from quantitative analysis becausetypical designs as represented by the prototypesdo not qualify for the exception.Smaller computer rooms will now needeconomizers.

AddendumCode SectionsAffectednTables 6.8.1-9,6.8.1-10qTable 6.5.3.1-2s6.5.2.1u6.5.7v5.5.4.5wMultiple,Chapters 3, 4, 5,6, 9, 12,Appendices A, B,D, E, G,ReferenceStandardReproductionAnnex (new)Table 2 Commercial Code Change Summary for ASHRAE 90.1- 2016 (continued)Included inImpact onCode Change Summary BetweenquantitativeASHRAE 90.1-2013 and ASHRAE 90.1-2016Energy UseAnalysisDiscussionModifies integrated energy efficiency ratio(IEER) values for air-cooled variable refrigerantflow (VRF) air conditioners and heat pumpsabove 65,000 Btu/h. The new IEERs are between15% and 20% more stringent.Allows only the following systems to use the fanpower allowance for fully ducted return and/orexhaust systems: (1) systems required to be fullyducted by code or accredited standards; (2)systems required to maintain air pressuredifferentials between adjacent rooms.Relieves parallel fan powered box and dedicatedoutdoor air system (DOAS) with direct digitalcontrol (DDC) from requirements c & d inexception 2 of Section 6.5.2.1.DecreasesEnergy UseNoExcluded from quantitative analysis becausetypical designs, as represented by the establishedprototypes, do not include VRF systems.DecreasesEnergy UseNoDecreasesEnergy UseNoApplies transfer air requirements more broadlythan to just kitchen exhaust systems, and clarifiesthe sources of transfer air.Deletes exception 2 of the fenestration orientationrequirement for obstructions to south-facingglazing.Refers 90.1 to new climatic data based onStandard 169-2013 resulting in changes to climatezone assignments for some locations, the creationof a new climate zone 0, and the addition ofcriteria for climate zone 0. Adds method for ratingthe solar reflectance index of walls with glassspandrel area and adjusts criteria for minimumskylight area in climate zone 0.DecreasesEnergy UseYesReduces fan energy through improved efficiencyin other components in designs that utilize ductedreturn or exhaust by choice. Excluded fromquantitative analysis because typical designs asrepresented by prototypes do not utilize this extrareturn or exhaust duct credit.Increases energy use because it allows somedesigns to avoid a requirement for two stages ofheating. Excluded from quantitative analysisbecause typical designs as represented by theprototypes do not include perimeter heating orparallel fan-powered terminal units.Makes transfer air requirements more stringent.DecreasesEnergy UseNoIncreasesEnergy UseYesDeletes the exception increasing stringency.Excluded from quantitative analysis becauseobstructions are not modeled in the prototypes.This change indirectly affects how climate zonesare defined and applied through Standard 90.1.For example, the recent update shifted a relativelysmall number of locations to warmer climatezones where they were typically subject to lessstringent requirements, therefore increasingenergy use in those instances. Impacts somecounties in south Florida.

AddendumCode SectionsAffectedacA9.4ag6.4.3.9ah9.4.1.1ai5.5.4.1, Tables5.5-0 through5.5-8aj6.5.3.2.1,6.5.3.2.4ak6.5.4.1, 6.5.4.3al5.4.3.2Table 2 Commercial Code Change Summary for ASHRAE 90.1- 2016 (continued)Included inImpact onCode Change Summary BetweenquantitativeASHRAE 90.1-2013 and ASHRAE 90.1-2016Energy UseAnalysisDiscussionAllows the use of the R-value of an airspace inenclosed cavities with or without insulation(Appendix A). Expands the R-value table inAppendix A (based on Chapter 26 of the 2009Handbook of Fundamentals).Limits mechanical cooling to 85 F for vestibules,except when the vestibule is tempered withtransfer air or heated with recovered energy.DecreasesEnergy UseNoSets criteria limiting when the R-value of airspaces may be included in calculations. Excludedfrom quantitative analysis because it did notchange opaque envelope U-factors if assembliesmodeled in the prototypes.Limits cooling setpoint in vestibules. Excludedfrom quantitative analysis because typical designsas represented by the prototypes do not includevestibules with cooling.Increases application of controls for emergencylighting.DecreasesEnergy UseNoClarifies that all lighting, including egress lightingon emergency circuits, shall be turned off whenthe space is unoccupied with 0.02 W/sf inexception.Prescribes lower solar heat gain coefficient(SHGC) for vertical fenestration in climate zone 0and lower U-factors for vertical fenestration inclimate zones 4 through 8.Requires return and relief fans larger than 0.5 hpto have variable frequency drive (VFD) control,to maintain building pressure, and to avoiddisabling of economizer operation.DecreasesEnergy UseYesDecreasesEnergy UseYesRequires more stringent window U-factor andSHGC.DecreasesEnergy UseNoAddresses a number of issues with hydronicsection (6.5.4.1) including removal of the pumppower threshold, limiting Section 6.5.4.1 toheating and cooling hydronic systems only,lowering the flow limit exception, and otherchanges.Prescribes air leakage criteria for metal coilingdoors in semi-heated spaces.DecreasesEnergy UseNoEnsures proper pressurization that allowseconomizers to function more efficiently.Excluded from quantitative analysis becausereturn and relief fans are not explicitly modeled inthe prototypes.Increases application of variable flow hydronicsystems and reduces the required minimum flow.Excluded from quantitative analysis because therequirement is standard practice that was alreadyassumed in the prototypes.DecreasesEnergy UseYesAdds coiling door air leakage requirements.

AddendumamCode SectionsAffected9.4.1.2Table 2 Commercial Code Change Summary for ASHRAE 90.1- 2016 (continued)Included inImpact onCode Change Summary BetweenquantitativeASHRAE 90.1-2013 and ASHRAE 90.1-2016Energy UseAnalysisDiscussionIncreases the parking garage lighting reductionfrom 30% to 50% in response to no occupancy,specifies a 50% reduction in lighting power inresponse to the presence of daylighting, andremoves a duplicate exception.Requires luminaires in parking areas with inputpower greater than 78W and mounting height lessthan 24 ft to reduce power by 50% in response tooccupancy.Clarifies and limits the exceptions to exhaust airenergy recovery requirements (6.5.6.1).DecreasesEnergy UseNoExcluded from quantitative analysis because theprototypes do not include parking garages.DecreasesEnergy UseYesAdds parking lot occupancy controls, therebyreducing parking lot lighting use.DecreasesEnergy UseNoExcluded from quantitative analysis because theexceptions are not used by typical designs asrepresented by the prototypes.Increases energy use because it potentiallyincreases heat loss through fluttering. Excludedfrom quantitative analysis because single-ply nonadhered roofing membranes are not included inthe prototypes.as9.4.1.4aw6.5.61ay5.4.3.1.3Allows non-adhered single-ply roof membranes toqualify as an air barrier material.IncreasesEnergy UseNobcTables 5.5.0through 5.5.8Lowers U-factor criteria for doors.DecreasesEnergy UseYesbi6.5.2.6Limits ventilation air heating (DOAS systems).DecreasesEnergy UseNobj6.5.4.7Establishes minimum chilled water coil selectiondelta T.DecreasesEnergy UseYesbk6.5.3.4Specifies control of fans in fan powered parallelVAV boxesDecreasesEnergy UseNoLimits simultaneous heating and cooling.Excluded from quantitative analysis because theDOAS system in the Large Hotel prototypealready meets this requirement.Reduces pumping energy.Includes several control strategies that reduceenergy use in fan powered terminal units.Excluded from quantitative analysis becausetypical design as represented by the prototypesdoes not employ parallel fan-powered terminalunits.