2017 SeaBEC Symposium. Advancing Building Enclosures Beyond Code Conformance. Medgar Marceau, PE Principal, Senior Building Science Engineer

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1 2017 SeaBEC Symposium Advancing Building Enclosures Beyond Code Conformance Medgar Marceau, PE Principal, Senior Building Science Engineer May 16, 2017 AIAMH123

2 2 Passive House and Commercial Construction -The Evolution of Residential Passive House Building Standards and the Application to Commercial Construction

3 Credit Eligibility: 1 - AIA CES LU HSW Credits will be reported to AIA by the SeaBEC organization. 3

4 Couse Description There is a large knowledge base of how to build durable residential buildings that meet the Passive House standard. However, there are few examples of commercial buildings meeting Passive House. This presentation will help bridge the knowledge gap between residential and commercial Passive House construction. 4

5 Learning Objectives Acknowledging the challenges in translating Passive House to Passive Commercial Solutions for minimizing thermal bridging in commercial construction Thermally efficient at-grade and below-grade transitions Using 2-D and 3-D simulation tools to evaluate hygrothermal performance Solutions for an air-tight interior vapor retarder 5

6 What is a Thermal Bridge? Highly conductive material that by-passes insulation layer Areas of high heat transfer Can greatly affect the thermal performance of assemblies 6

7 Parallel Path Heat flow total Area-weighted average of un-insulated assemblies In 2015 WA and Seattle Energy Codes Does not tell the whole story 7

8 Thermal Bridging Parallel path doesn t tell the whole story Many thermal bridges don t abide by areas ie: shelf angle Lateral heat flow can greatly affect the thermal performance of assemblies 8

9 Addressing Lateral Heat Flow 9

10 Lateral Heat Flow Parallel Path With Lateral Heat Flow 10 10

11 Overall Heat Loss Q Q o Qslab Additional heat loss due to the slab 11

12 Overall Heat Loss Qslab / L The linear transmittance represents the additional heat flow because of the slab, but with area set to zero 12

13 Types of Thermal Transmittances Clear Field U o Linear psi Point chi 13

14 Overall Heat Loss Total Heat Loss = Heat Loss Due To Clear Field + Heat Loss Due To Anomalies Q / T ( U A) o L 14

15 The Questions Why is Passive House criteria so much lower than the categories in the BETB? 15 Psi IP ᵠ Psi Metric (BTU/hr.ft. F) (W/mK) Thermal Bridge Free Typical Good Detail Typical Ok Detail Poor Detail Bad Detail Anything Past Here Brutal Anything Past Here is Brutal ᵠ

16 The Questions 16

17 The Questions How does PHPP predictions compare to dynamic models, in the context of recent BC policy work, thermal comfort, and when might both tools be required on project? 18

18 The Questions How can we meet the thermal performance challenges, as well as combustibility, structure, environmental separation, and durability requirements? 19

19 Objectives 1. Address questions about different methodologies for quantifying thermal bridging 2. Identify the key differences between static and dynamic simulation when assessing predicted building performance; 3. Identify the key differences in testing protocols for Heat Recovery Ventilators; 4. Provide design guidance and examples of how Part 3 buildings could meet high levels of performance similar to Passive House in BC 20

20 European Passivhaus Is different Sill Head Jamb R-44 R

21 North American Inclinations Clip and Rail System Thicker walls with more exterior insulation Extra insulation at floor slab Cavity Insulation R-38 22

22 PNW Construction Practice What is being considered in Alaska and in New York for Passive House is an indication of a mainstream response Condensation risk Occupant comfort High effective R-value Compressed construction duration 23

23 Accuracy Expectations ISO 14683:2007, section 5.1 Numerical calculations, typically ±5% Thermal bridge catalogues, typically ±20% Manual calculations, typically ±20% Default values, typical accuracy 0 to 50% Intent is to be conservative 24

24 Methodology Boundary Conditions Differences in Boundary Conditions PH (ISO) vs BETB Guide Exterior and Interior Temperatures Exterior and Interior Air Films Air Cavity Resistance 25

25 Methodology Boundary Conditions Differences in Boundary Conditions PH (ISO) vs BETB Guide Exterior and Interior Temperatures Exterior and Interior Air Films Air Cavity Resistance 26

26 Methodology Temperatures PHI (ISO): ISO BETBG: ASHRAE 1365 PHI(ISO): -10 o C BETBG: 0 PHI (ISO): 20 o C BETBG: 1 27

27 Methodology Air Films PHI (ISO): ISO 6946 BETBG: ASHRAE HoF Floor PHI (ISO): 5.9 W/m 2 BETBG: 6.1 W/m 2 Exterior PHI (ISO): 25 W/m 2 BETBG: 34 W/m 2 Ceiling PHI (ISO): 10 W/m 2 BETBG: 9.3 W/m 2 28

28 Methodology Air Films R-Value PHi (ISO): ISO 6946 BETBG: ASHRAE HoF Floor PHi (ISO): BETBG: R-0.96 R-0.93 Exterior PHi (ISO): BETBG: R-0.23 R-0.17 Ceiling PHi (ISO): BETBG: R-0.57 R

29 Methodology Air Spaces PHI (ISO): ISO BETBG: ASHRAE HoF PHI (ISO): BETBG: R (varies) R

30 Methodology Overall Values Clear Field U-Value PHI (ISO): BETBG: W/m 2 K W/m 2 K Slab Psi-Value PHI (ISO): BETBG: W/mK W/mK 31

31 2D versus 3D ISO

32 2D versus 3D 2D NFRC 20 to 33% 2D Modified 10 to 15% 3D Model 3% 33

33 Impact of Details Source: Passive House Canada 34

34 Impact of Details = 0.05 W/m K 35

35 Impact of Details Window interface triple glazed window, high levels of insulation, and mitigation of thermal bridging. Highlight sill, jamb, and head. Compare to overall transmittance for both detailed and simplified geometry. Intermediate floor higher levels of insulation, flashing, and how insulation in the stud cavity impacts 2D versus 3D flow assumptions. Base of wall thermal break and higher levels of insulation Balcony intermittent supported. Parapet higher levels of insulation and 2D versus 3D assumptions. 36

36 Illustrated Guide Design guidance suited to BC s climate and construction practices Challenges and opportunities around combustibility, structure, environmental separation, and durability Energy modeling considerations for Part 3 buildings equivalent to or approaching Passive House standard Outline how N.A. HRVs can be used in Passive House certified buildings 37

37 Passive Commercial projects in Seattle City s Renewable City Strategy: British Columbia s building trends affecting the Pacific Northwest markets. March 23, DJC How 'negawatts' help the building industry fight climate change THAT Council direct staff to build all new City-owned and Vancouver Affordable Housing Agency (VAHA) projects to be Certified to the Passive House standard or alternate zero emission building standard, and use only low carbon fuel sources, in lieu of certifying to LEED Gold unless it is deemed unviable by Real Estate and Facilities Management, or VAHA respectively, in collaboration with Sustainability and report back with recommendations for a Zero Emissions Policy for New Buildings for all City-owned and VAHA building projects by City of Vancouver RR-2, July 5, 2016 March 22, DJC SolHaus wins green award January 11, DJC This Lower Queen Anne apartment complex has passive house' design 38 September 13, DJC East Pike apartments will meet Passive House energy standards

38 7.3.2 Conventional Window Detail 39

39 7.3.2 Transmittance Detail 40

40 7.3.2 Thermal Performance 41

41 Assembly Performance 42

42 Passive House Window Detail 43

43 Window Detail Passive Thermal Performance data from Passive house detail, Patrick R. 44

44 Window Detail Passive Assembly Performance data from Passive house detail, Patrick R. 45

45 Passive House Window Detail Window Sill 46

46 Passive House Window Detail Window Head 47

47 Passive House Window Detail Window Jamb 48

48 Window Detail Thermal Performance Passive Thermal Performance data from, Patrick R. 49

49 Window Detail Assembly Performance Passive Assembly Performance from Patrick Ropel 50

50 Slab Edge Conventional Detail 51

51 Slab Edge Conventional Transmittance Detail 52

52 Slab Edge, Conventional Thermal Performance 53

53 Slab Edge, Conventional Assembly Performance 54

54 Passive House Slab Edge Detail 55

55 Slab Edge Detail Thermal Performance Thermal Performance, from Patrick Ropel 56

56 Slab Edge Detail Assembly Performance Assembly Performance, from Patrick Ropel 57

57 5.5.6 Parapet Cap Conventional Detail 58

58 5.5.6Parapet Cap Transmittance Detail 59

59 5.5.6 Parapet Cap Thermal Performance 60

60 5.5.6 Parapet Cap Assembly Performance 61

61 5.5.9 Parapet Cap, Thermally Broken Conventional Detail 62

62 5.5.9 Parapet Cap, Thermally Broken Transmittance Detail 63

63 5.5.9 Parapet Cap, Thermally Broken Thermal Performance 64

64 5.5.9 Parapet Cap, Thermally Broken Assembly Performance 65

65 Passive House Parapet Detail Parapet 66

66 Parapet Detail Thermal Performance PH Thermal Performance Data from Patrick 67

67 Parapet Detail Assembly Performance PH Assembly Performance Data from Patrick 68

68 7.6.4 Base of Wall, Below-Grade Conventional Detail 69

69 7.6.4 Base of Wall, Below-Grade Transmittance Detail 70

70 7.6.4 Base of Wall, Below-Grade Thermal Performance 71

71 7.6.4 Base of Wall, Below-Grade Assembly Performance 72

72 Passive House Base of Wall Detail Base of Wall 73

73 Base of Wall Detail Thermal Performance PH Thermal Performance Data from Patrick 74

74 Base of Wall Detail Assembly Performance PH Assembly Performance Data from Patrick 75

75 5.2.5 Typical Balcony Conventional Detail 76

76 5.2.5 Typical Balcony Transmittance Detail 77

77 5.2.5 Typical Balcony 5x Transmittance Detail 78

78 5.2.5 Thermal Performance 79

79 5.2.5 Assembly Performance 80

80 Passive House Balcony Detail, Isometric Intermittent Balcony 81

81 Balcony Detail Thermal Performance PH Thermal Performance Data from Patrick 82

82 Balcony Detail Assembly Performance PH Assembly Performance Data from Patrick 83

83 Passive House Balcony Detail cross section Intermittent Balcony 84

84 Balcony Detail Cross Section Thermal Performance PH Thermal Performance Data from Patrick 85

85 Balcony Detail Cross Section Assembly Performance PH Assembly Performance Data from Patrick 86

86 Hygrothermal window sill 87

87 88 Solutions for an air-tight interior vapor retarder

88 Thank You! Contact Medgar Marceau,