2014 Advanced Residential Energy Code Compliance: Methods, Tools and Verification

Transcription

1 2014 Advanced Residential Energy Code Compliance: Methods, Tools and Verification Special thanks to Ann Stanton of the Florida Department of Business and Professional Regulation and FSEC Buildings Research Division staff for a number of presentation materials Updated Spring 2015 Program for Resource Efficient Communities U of F. 1

2 Course introduction: This course is related to the Florida Building Code- Energy Conservation, 5 th Edition (2014) 2

3 Capacity (MBtu/h) Building Science COIL1_TEST_4B_10B_16B_22B 08/30/02 07:42:04 Cycle #1 (Comp ON time: 45.0 minutes) Sensible Off-Cycle Evaporation is Adiabatic Process: 0 Latent Removal -10 Compressor Latent Addition time (minutes) Average Temperatures ( o F) RWB: Max = 89.0 F RWF: Max= 87.8 F RWM: Max= 91.7 F RWS: Max= F RSL: Max= 83.2 F RGS: Max= F RTB: Max= 98.8 F 80 Summer Peak Period Time of Day (EST) 3

4 Building Science Health & Safety We can assure good indoor air quality Building durability We can avoid serious moisture damage Comfort We can assure occupant comfort Energy costs We can control energy use 4

5 Building Science Heat Transfer 5

6 Building Science Three modes of heat transfer Conduction Convection Radiation Heat Transfer 6

7 Building Science Conduction the transfer of heat through matter by communication of kinetic energy from particle to particle with no net displacement of the particles Heat Transfer Definition used by permission. >From Merriam-Webster s Collegiate Dictionary, 11th Edition 2010 by Merriam-Webster, Incorporated ( 7

8 Building Science Convection the circulatory motion that occurs in a fluid at a nonuniform temperature owing to the variation of its density and the action of gravity Heat Transfer Definition used by permission. >From Merriam-Webster s Collegiate Dictionary, 11th Edition 2010 by Merriam-Webster, Incorporated ( 8

9 Building Science Radiation Energy [proceeding in a direct line from or toward a center] in the form of waves or particles Heat Transfer Definition used by permission. >From Merriam-Webster s Collegiate Dictionary, 11th Edition 2010 by Merriam-Webster, Incorporated ( 9

10 Building Science Moisture Movement 10

11 Building Science Building Moisture Sources Bulk moisture (i.e., rain water & ground water) Internally generated moisture Diffusion thru building envelope materials Infiltration of moisture-laden outside air Ventilation air Capillary flows 11

12 Building Science Liquid Bulk flow Capillary suction Vapor Air transport Diffusion Moisture Movement 12

13 Building Science Bulk flow Moisture Movement Groundwater and rainwater moving under the influence of a driving force such as gravity or air pressure. 13

14 Building Science Capillary suction Moisture Movement Water movement into porous materials; is a function of pore size and available moisture 14

15 Building Science Moisture Movement Air Transported holds moisture and moves across a hole by an air pressure difference carrying the moisture with it. 150 Pints of Water During cooling season in Orlando 15

16 Building Science Moisture Movement 16

17 Moisture/Pressure Difference Building Science 17

18 Building Science Diffusion Moisture Movement The movement of moisture in the vapor form through a material. It is a function of material permeability and vapor pressure differential. 18

19 High indoor RH and mold/mildew contamination leading to serious IAQ problems Building Science Humidity Effects 19

20 Building Science Moisture must be available There must be a pathway There must be a force to cause movement Materials must be susceptible to damage Theory- Totally eliminate any one for complete control Reality- Moisture Control Take of as many and to the extent possible. 20

21 Building Science Uncontrolled Air Flow (UAF) 21

22 Building Science Uncontrolled Air Flow (UAF) Air moving across the building envelope or between zones or cavities of the building, where the pathways of flow, the direction of flow, and the origin of the air are unknown, unspecified, or unintended. 22

23 Building Science Uncontrolled Air Flow Duct Leakage 23

24 Building Science Uncontrolled Airflow Duct Leakage 24

25 Building Science Uncontrolled Airflow Wind Washing Withers, C. and Cummings, J. Opportunities for Energy Conservation and Improved Comfort From Wind Washing Retrofits in Two-Story Homes Part I, Seventeenth Symposium on Improving Building Systems in Hot and Humid Climates, August 24, 2010, in Austin, TX. 25

26 Building Alignment Air & Thermal Barrier Alignment Heat flow Air flow Heat flow Air flow Air barrier Insulation Insulation 26

27 Building Science Uncontrolled Airflow Door Closure 27

28 ach Building Science Uncontrolled Airflow Door Closure Closing interior doors with AH fan on All Closed closed closed 0.62 Open 0.42 Open 0.16 fan off fan on Open Open 2 closed 4 closed All Closed 28

29 Building Science Uncontrolled Airflow Door Closure Pressure Relief 29

30 Building Science Uncontrolled Airflow Door Closure Pressure Relief 30

31 Building Science Building Loads 31

32 Building Science Location, Location, Location... Minneapolis: 12º F Indoor Temp: 70º F Miami: 47º F 32

33 Building Science So for example, heat gain (conduction) through walls isn t as big of an issue here but we do have some solar heat gain to deal with! 33

34 Building Science Cooling Loads Annual Cooling Load Components Tampa FL, 2,000 sq. ft. Residence 34

35 Building Science Window Heat Flows 35

36 Building Science Reducing Window Heat Flows 36

37 Building Science Solar Heat Gain Coefficient (SHGC) Ratio of the solar heat gain entering the space through the fenestration assembly to the incident solar radiation Number between 0 & 1 Lower SHGC transmits less solar heat. 37

38 Building Science Visible Transmittance (VT) Transmittance of glazing material over the visible portion of solar spectrum Higher VTs maximize daylight and view. 38

39 Building Science Heat Lost (U-Factor) The coefficient of heat transmission (air to air) through a building component or assembly Low U-factor reduces the transfer of heat relative to a higher U-factor window

40 Building Science The Building as a System Supply leak Vented Attic AHU Supply Return 40

41 Number of houses Building Science The Building as a System < Fan off air change rate Fan on >2.0 41

42 Building Science The Building as a System Perception of Reality Is this real? Reality See Touch Smell Taste Hear Concept of Reality 42

43 Building Science So the only way to be sure is to test. 43

44 Some Recent Code History Executive Order The Secretary of Community Affairs shall : Convene the Florida Building Commission for the purpose of revising the Florida Energy Code for Building Construction to increase the energy performance of new construction in Florida by at least 15% from the 2007 Energy Code. The Commission should consider incorporating standards for appliances and standard lighting in the Florida Energy Code.

45 Some Recent Code History House Bill 7135 H.B requires that: the 2009 IECC become the foundation code for the FEC the 2010 FEC achieve a 20% increase in new home energy efficiency relative to the 2007 FEC. Additional increases (e.g. 50% increase in efficiency by 2019) no longer in place

46 Residential Code Effectiveness Fairey, P., Effectiveness of Florida's Residential Energy Code: , Florida Solar Energy Center, FSEC-CR , June 15, 2009.

47 2010 Code Quick Overview

48 2010 Code Overview Residential Compliance Paths - Changed Compliance. Projects shall comply with Sections 401, 402.4, 402.5, and 403.1, , , and through (referred to as the mandatory provisions) and either: 1.Sections through 402.3, and (prescriptive); or 2. Section 405 (performance).

49 Show 402 table Code Overview Prescriptive-Based Compliance Exceptions for additions.

50 2010 Code Overview Prescriptive Alternatives - Changed U-factor alternative An assembly with a U-factor equal to or less than that specified in Table can be used as an alternative to the corresponding component R-value in Table Total UA alternative if the total building thermal envelope UA is less than or equal to the total UA resulting from using the U- factors in Table the building is considered in compliance with Table

51 2010 Code Overview U-factor Alternative - Changed TABLE EQUIVALENT U-FACTORS Crawl Space Wall U-Factor Basement Wall U-Factor Floor U-Factor Mass Wall U- Factor Frame Wall U-Factor Ceiling U-Factor Skylight U-Factor Fenestration U- Factor

52 2010 Code Overview Performance-Based Compliance - Changed Performance based compliance Compliance based on simulated energy performance requires that a proposed residence (proposed design) be shown to have an annual normalized, modified energy load that is less than or equal to 80% of the annual energy load of the Standard Reference Design.

53 2010 Code Overview Performance-Based Compliance - same A performance-based code approach looks at the potential annual energy performance for the whole building (heating, cooling & hot water) Compliance with Chapter 405 of the Florida Building Code, Energy Conservation is a performance-based approach.

54 2010 Code Overview Performance-Based Compliance - changed TABLE B-1.1.2(1) SPECIFICATIONS FOR THE STANDARD REFERENCE AND PROPOSED DESIGNS Building Component Above-grade walls Standard Reference Design Type: Wood frame Gross area: same as proposed Proposed Design As proposed As proposed Conditioned basement walls U-Factor: Solar absorptance = 0.75 Emittance = 0.90 Type: same as proposed Gross area: same as proposed U-Factor: 0.36 with the insulation layer on the interior side of walls As proposed As proposed As proposed As proposed As proposed As proposed

55 2010 Code Overview Weighted Averaging - changed 7% 80% 13%

56 2010 Code Overview Additions, alterations, renovations or repairs. Additions, alterations, renovations or repairs to an existing building, building system or portion thereof shall conform to the provisions of Table th Edition - separate definitions for each.

57 5 th Edition (2014) Florida Building Code: Energy Conservation

58 2014/5 th Edition Overview Other Related Renovated Building [from Ch. 2 Definitions]. A residential or nonresidential building undergoing alterations that varies or changes insulation, HVAC systems, water heating systems, or exterior envelope conditions, provided the estimated cost of renovations exceeds 30% of the assessed value of the structure. Addition. An extension or increase in conditioned space floor area or height of a building or structure.

59 2014 Code Overview Other Related Alteration [from Ch. 2 Definitions]. Any construction or renovation to an existing structure other than repair or addition that requires a permit. Also, a change in a mechanical system that involves an extension, addition or change to the arrangement, type of purpose of the original installation that requires a permit.

60 2014 Code Overview Other Related Energy Ratings include appliances and lights while the Florida Energy Code continues to only include space heating, cooling and water heating.

61 5 th Edition (2014) FEC Base Code changes from 2009 IECC to 2012 IECC Parallel commercial and residential chapters ( CE and C vs. RE and R ) Florida specific changes through Code modification cycle over past ~18 months Performance max. e-ratio = 1.0 Several std. reference design value changes Effective date: June 30, 2015.

62 5 th Edition (2014) FEC Similar Residential Compliance Paths 2010 Code Compliance. Projects shall comply with 2014 Code Sections 401, 402.4, 402.5, and 403.1, , , and Compliance. through Projects (referred shall to as comply with the mandatory Sections provisions) identified and as either: mandatory and with either sections identified as prescriptive or the 1.Sections through 402.3, and performance approach in Section R (prescriptive); or 2. Section 405 (performance).

63 5 th Edition (2014) FEC Selected Mandatory Provisions 2010 Code Section 402.4: Tested air Leakage < 7 ACH50 or visual inspection Code Section R402.4: Tested air Leakage <= 5 ACH50 and envelope component installation specifications; where required by the code official, testing shall be conducted by an approved third party.

64 5 th Edition (2014) FEC Selected Mandatory Provisions 2010 Code Section 402.5: Maximum area-weighted average fenestration SHGC of 0.5 (exception if window area-weighted average overhang depth for the entire dwelling unit is 4.0 feet 2014 or greater). Code [But Table is more stringent so ] Same requirement moved to Section R since only applies to performance compliance.

65 5 th Edition (2014) FEC Selected Mandatory Provisions 2010 Code Duct tightness. Duct tightness shall be verified by testing to ASHRAE Standard by either Code a Class 1 BERS rater or a Class A, B or Mechanical air-conditioning contractor. All ducts Sealing and air handlers (Mandatory). shall be either located in conditioned Duct tightness space shall or be tested verified by a by Class testing 1 BERS to Section 803 of rater to be substantially the RESNET leak Standards free by by one either of the an following energy rater certified methods in accordance with Section , Florida Statutes, or as authorized by Florida Statutes, to be substantially leak Exception: free Duct by testing either is of not the mandatory following for buildings complying by Section 405 of this code. Exception [2]: Duct testing is not mandatory for buildings complying by Section 405 of this code.

66 Prescriptive-Based Compliance Show 402 table. 5 th Edition (2014) FEC

67 5 th Edition (2014) FEC Prescriptive-Based Compliance 2010 Code Section : U-factor alternative An assembly with a U-factor equal to or less than that specified in Table can be used as an alternative to the corresponding component R-value in Table Section Total 2014 UA alternative Code if the total building thermal envelope UA is less than or equal to Same the total alternatives UA resulting included, from using but now the two U-factors Climate in Table Zones and changes the building to several is considered U-factors. in compliance with Table

68 5 th Edition (2014) FEC Performance-Based Compliance

69 5 th Edition (2014) FEC Performance-Based Compliance Selected Standard Reference Design Values Component 2010 Reference 2014 Reference Window Area 18% GFA As proposed if < 15% GFA o/w 15% GFA Window U-Factor / SHGC 0.75 / (1), 0.40 (2) / 0.25 Ceiling U-factor (1), (2)

70 5 th Edition (2014) FEC Performance-Based Compliance Typical 2000 sq. ft. Tampa block home: 0.30 SHGC SEER 13 / HSPF 7.7 HP Qn = 0.05 attic ducts

71 5 th Edition (2014) FEC Performance-Based Compliance Similar home with 480 sq. ft. of glass (0.24 GFA) vs. 300 sq. ft. of glass (0.15 GFA)

72 Duct Sealing Section requires duct sealing for total condenser and evaporator replacements for residential buildings: all accessible (a minimum of 30 inches clearance) joints and seams shall be inspected and sealed where needed." Exceptions: Equipment Replacements 1) Ducts in conditioned space 2) Joints or seams that are already sealed with fabric and mastic 3) If system is tested and repaired as necessary.

73 Duct Sealing Section requires duct sealing for total condenser and evaporator replacements for residential buildings: all accessible (a minimum of 30 inches clearance) joints and seams shall be inspected and sealed where needed." Exceptions: Equipment Replacements 1) Ducts in conditioned space 2) Joints or seams that are already sealed with fabric and mastic 3) If system is tested and repaired as necessary.

74 Equipment Replacements System Sizing Section , "a nationally recognized method based sizing calculation" is to be used for total condenser and evaporator replacements for residential buildings Section (for residential): heating and cooling equipment are to be sized according to ACCA Manual S "based on the equipment loads calculated in accordance with Manual J or other approved heating and cooling calculation methodologies..."

75 Equipment Replacements System Sizing Section , "a nationally recognized method based sizing calculation" is to be used for total condenser and evaporator replacements for residential buildings Section (for residential): heating and cooling equipment are to be sized according to ACCA Manual S "based on the equipment loads calculated in accordance with Manual J or other approved heating and cooling calculation methodologies..."

76 Code Updates

77 Chapter 4 and Appendix B Overview 77

78 Chapter 4 and Appendix B Overview Residential Compliance Paths Compliance. Projects shall comply with Sections identified as mandatory and with either sections identified as prescriptive or the performance approach in Section R405. R405 Simulated Performance Alternative (Performance) 78

79 Chapter 4 and Appendix B Overview Mandatory Provisions Section 402 Building Thermal Envelope Air Leakage Section 403 Systems Thermostat provision Sealing (ducts) Building cavities Heat traps 79

80 Chapter 4 and Appendix B Overview Mandatory Provisions Section 403 Systems Water heating efficiencies Mechanical ventilation Heating and cooling equipment Section 404 Electric Power and Lighting Systems 80

81 Chapter 4 and Appendix B Overview Mandatory Provisions Section 403- Systems Section Controls (including thermostat provision for at least 1 thermostat provided for each separate heating and cooling system) 81

82 Chapter 4 and Appendix B Overview Mandatory Provisions Section Systems Sealing (Mandatory). Duct tightness shall be verified by testing to Section 803 of the RESNET Standards by either an energy rater certified in accordance with Section , Florida Statutes, or as authorized by Florida Statutes, to be substantially leak free by either of the following Exception [2]: Duct testing is not mandatory for buildings complying by Section 405 of this code. 82

83 Chapter 4 and Appendix B Overview Mandatory Provisions Section 403- Systems 1. Postconstruction test: Total leakage less than or equal to 4 cfm per 100 ft 2 of conditioned floor area when tested at a pressure differential of 0.1 inches w.g. (25 Pa) across the entire system, including the manufacturer s air handler enclosure. 83

84 Chapter 4 and Appendix B Overview Mandatory Provisions Section 403- Systems (continued) 2. Rough-in test: Total leakage less than or equal to 4 cfm per 100 ft 2 of conditioned floor area when tested at a pressure differential of 0.1 inches w.g. (25 Pa) across the entire system, including the manufacturer s air handler enclosure or 3 cfm per 100 ft 2 if no air handler. 84

85 Chapter 4 and Appendix B Overview Mandatory Provisions Section 403- Systems (continued) Building cavities. Building framing cavities shall not be used as ducts or plenums Heat Traps. Storage water heaters not equipped with integral heat traps and having vertical risers shall have heat traps installed on both inlets and outlets. 85

86 Chapter 4 and Appendix B Overview Mandatory Provisions Section 403- Systems (continued) Water heater efficiencies Storage water heater temperature controls Water heating equipment Solar water heating systems 86

87 Chapter 4 and Appendix B Overview Section 403- Systems (continued) Mechanical Ventilation. Whole-house mechanical ventilation Ventilation air Heating and cooling equipment. Equipment sizing Capacity Mandatory Provisions Systems serving multiple dwelling units 87

88 Chapter 4 and Appendix B Overview Mandatory Provisions Section 404 Electric Power and Lighting Systems Lighting Equipment. A min. of 75% of the permanently installed light fixtures shall be high-efficacy lamps or a min. of 75% of permanently installed fixtures shall contain high efficacy lamps. 88

89 Section 402 (Prescriptive) Compliance 89

90 Section 402 Compliance Section 402 Prescriptive Building Thermal Envelope compliance (also formerly 1100B-08) requirements from Table (partial): Differs by Climate Windows: Max. U-0.65 (skylights 0.75), SHGC 0.25, Walls: Frame R-13, Block R-6 / R-7.8 Ceilings: R-30/R-38 Floors: R-13 raised floor; R-0 slab-on-grade Equipment efficiency: code minimums by equipment and fuel type Ducts: R-8, exempt if located in conditioned space and tested Qn=

91 Section 402 Compliance 91

92 U-factor Alternative and Total UA Alternative U-factor Alternative Table is now Table EQUIVALENT U-FACTORS Crawl Space Wall U-Factor Basement Wall U-Factor Floor U-Factor Mass Wall U-Factor Frame Wall U-Factor Ceiling U-Factor Skylight U-Factor Fenestration U- Factor

93 Section 405 (Performance) Compliance 93

94 Section 405 Compliance Section 405 Performance Compliance Mandatory provisions in R401.2 be met and R-6 minimum on all supply and return ducts (outside thermal envelope) An annual energy load is calculated for the house to be built assuming certain standard reference design features Specification for the Standard Reference and Proposed Design now found in Table (1). An annual normalized, modified energy load is simultaneously calculated for the house with actual proposed design features 94

95 Appendix B: Calculation of End Use Energy No longer contains calculation procedure and software tools specifications (Table B (1)) Energy Loads for code compliance 95

96 Code Compliance and Energy Savings Improvement Options 96

97 Improvement Options 97

98 Improvement Options E-Ratio Weighting 98

99 Improvement Options vs.? Envelope Equipment 99

100 Improvement Options Cool Roofs Seven homes with same floor plan, orientation, equipment and insulation 100

101 Improvement Options Cool Roofs Seven homes with same floor plan, orientation, equipment and insulation Seven different roofing systems: Control gray shingle White shingle White barrel tile Terra cotta barrel tile White flat tile White metal seam Sealed attic (gray shingle) 101

102 Improvement Options: Cool Roofs Average Cooling Energy Use Over Unoccupied Period Average Electrical Demand (Watts) RWB Avg = 13.3 kwh/day RWF Avg = 13.3 kwh/day RWM Avg = 12.2 kwh/day RWS Avg = 15.6 kwh/day RSL Avg = 14.9 kwh/day RGS Avg = 17.0 kwh/day RTB Avg = 16.2 kwh/day Impact of East facing glass (RWB, RWF, RWS) West facing glass (RGS,RTB,RSL, RWM) Time of Day (EST) Summer Peak Period 102

103 Improvement Options Cool Roofs Estimated Normalized Average Savings for 1770 Square Foot Home Cool Savings Peak Demand Reduction RGS (Control): RWS (White Shingle): 4% 17% RSL (Sealed Attic): 9% 5% 103

104 Improvement Options High Efficiency Air Conditioners SEER 13 Minimum (January 2006) Over SEER 20 now available. 104

105 Improvement Options High Efficiency Air Conditioners Central Florida Example House (2,000 sq. ft., Garage AH, Ducts in Attic) SEER / HSPF: e-ratio Annual Cost* 13 / 7.7 (Base) 1.00 $1, / $1, / $1, / $1,576 $0.12 / kwh 105

106 Improvement Options Duct and Air Handler Location 106

107 Improvement Options Duct and Air Handler Location Central Florida Example House (2,000 sq. ft., Ducts in Attic) AH Location: e-ratio Annual Cost* Attic 1.04 $1,706 Garage 1.00 $1,688 Interior 0.99 $1,682 + Interior Ducts 0.93 $1,642 $0.12 / kwh 107

108 S y s te m E E R Improvement Options Duct Sealing Cooling System w/ Return Leaks Effective System EER Source:Contracting Business Apr94, Solving Leakage & Return Problems by Percent Leak 120 degf 110 degf 95 degf 108

109 Improvement Options Duct Sealing Central Florida Example House (2,000 sq. ft., Garage AH, Ducts in Attic) Duct Leakage: e-ratio Annual Cost* Default 1.00 $1,688 Substantially Leak Free 0.95 $1,651 $0.12 / kwh 109

110 Improvement Options Solar Water Heating 110

111 Improvement Options Solar Water Heating Central Florida Example House (2,000 sq. ft., 3 Bedroom) Water Heating Type: e-ratio Annual Cost* Electric EF= $1,688 $0.12 / kwh Example Solar 0.86 $1,

112 Improvement Options Improvement Options Exercise Code Cycle Method A (Performance) Max. e-ratio

113 Florida Energy Code Compliance Software

114 Improvement Options Improvement Option Exercise 114

115 Improvement Options The Lakeland House Project 115

116 Improvement Options 116

117 Cost of Conserved Energy (cents/kwh) Energy Savings (MWh/year) Improvement Options EERE Measures for Miami (Sorted by increasing CCE) Shng Wwalls Ducts Current residential retail price Cost of Conserved Energy (CCE) TaxC Fridg Lgts cfan estar dwash HAcloths Pkg1 WinU RBS HVAC2 Misc IDucts HWwrap HPWH SHW HW Pstat Pkg2 HRU 2kW-PV WallR HVAC3 Roof Annual Energy Savings Fairey, P. and J. Sonne, Effectiveness of Florida's Residential Energy Code: , Florida Solar Energy Center, FSEC-CR , May. 15,

118 Residential Energy Code Forms 118

119 Section 402 Forms 119

120 Section 402 Forms 120

121 Section 405 Forms 121

122 Section 405 Forms 122

123 Using Forms for Compliance Verification 123

124 Compliance Verification Check Lines for Form R (similar to 2010) 124

125 Compliance Verification Check Lines for Form R (similar to 2010) EnergyGauge USA FlaRes2014 Section R Compliant Software 125

126 Permitting Verification Verify that wall and window orientations on compliance form match the plans Verify window count, overhangs, U-factors, SHGCs and areas match the plans and specifications ( window area shaving sometimes used to comply with more rigid code) Attic knee walls (interior and exterior) Check that specified HVAC equipment efficiencies match those on the form Check AC equipment sizing calculation vs. entry 126

127 Field Verification Verify that wall and window orientations on compliance form match the actual building Verify window count, overhangs, U-factors, SHGCs and areas (window area shaving sometimes used to comply with more rigid code) Attic knee walls (interior and exterior) Check efficiencies of installed HVAC equipment and water heaters against the efficiencies on compliance form (using model numbers) Verify air handler location Verify if tested house airtightness and/or duct airtightness reports are required 127

128 Verification Exercise 128

129 Additional Resources Department of Business & Professional Regulation Online Codes and Standards Online Code Access Code Modifications Contact Information 129

130 Additional Resources FSEC Publications 130

131 Craig Miller University of Florida Contact Information 131