Roof Coatings Manufacturers Association October 18, 2012

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1 Roof Coatings Manufacturers Association October 18, 2012 Examples of Addressing New Fire Challenges & Risks With Science Bob Backstrom Kevin Faltin UL and the UL logo are trademarks of UL LLC 2012

2 New Fire Challenges Impact of the deployment of alternative energy devices (PV) on fire. Research: o o o CA Energy Commission / CALFIRE - wild land fire exposure ember mitigation DHS - PV & firefighter Safety DOE - PV & roof fire ratings

3 CA Energy Commission / CALFIRE Photographs courtesy of CALFIRE, the Center for Fire Research and Outreach and UL research project.- PV and Fire Fighter Safety

4 CA Energy Commission / CALFIRE Wild land fire exposure - ember mitigation: Screen Efficacy Operating Temperatures Project is ~ 90% completed, report will be forwarded to the Commission & CALFIRE 4

5 DHS / Assistance to Firefighters Grant PV and Firefighter Safety This project included experiments to investigate the shock hazard due to: Presence of water and PV power during a fire event Direct contact with energized components Damaged PV modules and systems Severing of conductors Low light conditions Emergency disconnect and disruption techniques Photos courtesy of 5

6 PV / Firefighter Training and Formal Report Photographs courtesy of the San Jose FD, Orange County FD and UL research project. - PV and Fire Fighter Safety 6

7 PV / Firefighter Training and Formal Report 7

8 Solar ABCs PV Flammability Project

9 Jurisdictional (AHJ) Concerns As a result of catastrophic fires in California, increasing parts of the state now require a Class A fire rating of all roofing products. This raised concerns over ambiguities with regard to the most common residential PV roof installation, Class C rated PV modules mounted over Class A rated roofs. Roof coverings and PV modules are rated separately. Little work had been done to investigate the interactions between them. Note: Building Integrated Photovoltaics above does not apply

10 Solar ABCs / UL Research Project Since the summer of 2009, the Solar America Board for Codes and Standards (Solar ABCs) in partnership with Underwriters Laboratories (UL), has designed and conducted specific tests to characterize the effects of stand-off mounted PV modules on the fire rating of Class A rated roofing systems All tests were conducted and directed by UL with some tests witnessed and directed by representatives of Solar ABCs. Acknowledgement: This material is based upon work supported by the Department of Energy under Award Number DE-FC36-07GO17034.

11 Solar ABCs / UL Research Project Phases of Project Phase 1: a) Develop an better understanding of the Spread of Flame Test through baseline experiments b) Test PV modules over roofs (various configurations and types) Spread of Flame and Burning Brand c) Determine effect of mitigation methods Phase 2: Test PV modules at different angles, directly on roof, and better understand the heat load of burning brands

12 Solar ABCs / UL Research Project Phases of Project Phase 3: Characterization of PV Materials Critical Radiant Flux Phase 4: Proof of concept of 3 SEIA 2015 IBC proposals to see if they address fire rating issues Phase 5: Test concept of first to ignite, second to ignite concept module/roof perimeter interface

13 Solar ABCs / UL Research Project

14 Solar ABCs / UL Research Project - Titles of Reports 1. Effect of Roof-Mounted Photovoltaic Modules on the Flammability of Roofing Assemblies, September 30, 2009, Revised March 5, Effect of Rack Mounted Photovoltaic Modules on the Flammability of Roofing Assemblies Demonstration of Mitigation Concepts, September 30, 2009, Revised February 10, Effect of Rack Mounted Photovoltaic Modules on the Fire Classification Rating of Roofing Assemblies, January 30, Characterization of Photovoltaic Materials Critical Flux for Ignition/Propagation, January 16, Determination of Effectiveness of Minimum Gap and Flashing for Rack Mounted Photovoltaic Modules, March 29, Considerations of Module Position on Roof Deck During Spread of Flame Tests, July 24, 2012 Copies of these reports are available at: 14

15 Solar ABCs Research Project Investigate whether and how the presence of standoffmounted PV arrays may affect the fire class rating of common roof covering materials.

16 Solar ABCs Research Project This Project applies to rack mounted only BIPV Rack Mounted

17 Noncombustible Roof, No PV Spread of Flame Baseline

18 Noncombustible Roof & PV Spread of Flame Independent Mounts, 0 Set Back, 10 & 2.5 Gaps PV at 0 Set back & 10 Gap PV at 0 Set back & 2.5 Gap

19 Noncombustible PV / Roof Temperature & Heat Flux Data

20 PHASE 1a - Effect of Rack Mounted Photovoltaic Modules on the Flammability of Roofing Assemblies Baseline Experiments Results Any panel (even noncombustible) increased the temperature and heat flux present at the roof surface when the flames were applied between the panel and roof 5 in. gap was worst case (10 in. was best) 5 in. is most consistent with installation methods best cooling relative to aesthetics 12 in. and 24 in. offset (setback) decreased intensity of flame, but still greater than the roof alone

21 PHASE 1b - Effect of Rack Mounted Photovoltaic Modules on the Flammability of Roofing Assemblies Module Over Roofs Conduct spread of flame and burning brand tests on a limited number of PV module/roof combinations Determine the effect of varying selected PV installation parameters such as stand-off height, leading edge distance, rail orientation, etc. Document the impact of lesser fire rated PV modules on common roofing assemblies Demonstrate if the fire classification rating of a roof system is affected by the presence of a rack mounted PV modules

22 PHASE 1b - Modules Over Roofs Class C PV & Class A Shingle 5 Gap Vertical Rails Class C PV & Class A Shingle 5 Gap - Horizontal Rails Not compliant (Class A) Not compliant (Class A)

23 PHASE 1b - Modules Over Roofs Spread of Flame on Various Roofing Types Test Gap Edge Roof PV Distance Time Code System Test (in) (in) Rating - Type Rating (feet) (Min:Sec) Spread of Flame 5 0 A - 3 Tab Shingle A 8 4: Spread of Flame 5 0 Noncombustible C 8 2: Spread of Flame 5 0 C - Wood Shake C 8 0: Spread of Flame 5 0 A - membrane A 8 1: Spread of Flame 5 0 A - Architectural Shingle C 8 1: Spread of Flame 5 0 A - Hot Mopped C 8 1:43

24 PHASE 1b - Modules Over Roofs Membrane Roof System Architectural Shingle

25 PHASE 1b - Modules Over Roofs Hot Mop Built-Up Roof Wood Shake Roof

26 PHASE 1b - Effect of Rack Mounted Photovoltaic Modules on the Flammability of Roofing Assemblies Modules Over Roofs SUMMARY The presence of a rack mounted PV module on a roof has an impact on the fire classification rating of the roof, regardless of: the fire classification rating of the roof or the fire classification rating of the PV panel

27 PHASE 1c - Effect of Rack Mounted Photovoltaic Modules on the Flammability of Roofing Assemblies Mitigation Methods Given the noncompliant results from the unprotected module tests, mitigation methods were tested to determine effectiveness Flashings, Screens, and Angled Deflectors Combinations with setbacks of 24 in. and 36 in.

28 PHASE 1c - Effect of Rack Mounted Photovoltaic Modules on the Flammability of Roofing Assemblies Mitigation Methods RESULTS Some experiments with noncombustible flashings and screening showed great promise, others did not The greatest temperature rise was observed when the PV modules were placed in line with the leading edge of the roof Increasing the offset distance resulted in lower surface temperature measured on the roof

29 PHASE 2 - Effect of Rack Mounted Photovoltaic Modules on the Fire Classification Rating of Roofing Assemblies Test PV modules at angles, directly on roof, and understand heat load of burning brands Test at positive and negative angles Flame impingement on top and at front of module mounted directly to roof

30 PHASE 3 - Characterization of Photovoltaic Materials Critical Flux for Ignition / Propagation Critical Radiant Flux experiments for the ignition of PV modules and roofing was attempted to develop more standardized tests

31 PHASE 4 - Report of Experiments of Minimum Gap and Flashing for Rack Mounted Photovoltaic Modules Objective was to experimentally test the concepts to support IBC proposals. Objective was to determine if these concepts addressed fire rating issues 2015 IBC Exceptions Proposed were: Exception for 12 in. gap as being Class A Compliant Exception for 0 gap as being Class A Compliant Metal leading edge as being Class A Compliant

32 PHASE 4 - Report of Experiments of Minimum Gap and Flashing for Rack Mounted Photovoltaic Modules RESULTS 12 in. gap only works for Steep Slope (not very aesthetic) Zero gap tested earlier and is compliant. ½ in. flashing only works for steep slope ONLY A PARTIAL SOLUTION SO ANOTHER APPROACH IS NEEDED

33 PHASE 5 - Considerations of Module Position on Roof Deck During Spread of Flame Tests NEW OBJECTIVE Working Task Group for UL1703 proposed the concept of igniting roof first, and then tracking fire progression into module mounting region Objective of this Phase was to test concept of first-to-ignite, second-to-ignite (FTI / STI)

34 PHASE 5 - Considerations of Module Position on Roof Deck During Spread of Flame Tests FOCUS Develop baseline fire performance of standard roof types for UL1703 Determine distance from flame source that provides a representative stresses roof/module interface point sufficient to differentiate the performance of PV designs and mounting designs Use non-combustible surrogate module to help discover the critical set back distances

35 PHASE 5 - Considerations of Module Position on Roof Deck During Spread of Flame Tests (June 2012) FTI/STI Steep Slope

36 DRAFT REVISIONS TO UL1703 Project has been completed and report issued: Fire working group has developed a new assembly (PV & roof) fire test. Formal proposal will be submitted to the UL 1703 STP for consideration and ballot: - Spread of Flame on surface of PV now involves testing on a plywood deck - Spread of Flame will additionally apply flame in between standardized low and steep slope roofs and PV rather than just on the surface of the module - Class A Burning Brand test on surface of PV now conducted with a standardized steep slope roof covering - Class B Burning Brand test is applied between with a standardized steep slope roof covering beneath the PV module - Modules not tested individually. PV systems are tested based on type of module (Glass/polymer; Glass/Glass)

37 Recap - UL1703 Proposed Revisions Spread of Flame on surface of PV now involves testing on a plywood deck Spread of Flame will additionally apply flame in between the standardized low and steep slope roof and PV rather than just on the surface of the module Class A Burning Brand test on surface of PV now conducted with a standardized steep slope roof covering Class B Burning Brand test is applied between with a standardized steep slope roof covering beneath the PV module Modules not tested individually. PV systems are tested based on type of module (Glass/polymer; Glass/Glass)

38 Solar ABCs PV Flammability Activities

39 Thank You. Bob Backstrom 39