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1 THE DEVELOPMENT OF FM APPROVAL STANDARDS FOR CLASS ONE STEEP ROOF COVERS, FLEXIBLE PHOTOVOLTAIC MODULES, AND VEGETATIVE ROOF SYSTEMS BY DAVID L. ALVES FM APPROVALS 1151 Boston Providence Turnpike, Norwood, MA MICHAEL C. BURKE Phone: (781) Fax: (781) E mail: michael.c.burke@fmapprovals.com JILL E. NORCOTT, PE Phone: (401) Fax: (401) E mail: jill.norcott@fmapprovals.com 2 6 T H R C I I N T E R N A T I O N A L C O N V E N T I O N A N D T R A D E S H O W A P R I L 7 1 2, A L V E S, B U R K E, A N D N O R C O T T 3 7

2 ABSTRACT FM Approval Standards 4475, 4476, and 4477 are the first comprehensive standards to evaluate steep-slope roof covers, flexible photovoltaic modules, and vegetative roofs, respectively. Failures of these types of roof coverings occur as a result of high winds, hailstorms, and exposure to fire from above and below the roof deck. Current industry practice for evaluation of these types of covers is generally limited to individual performance tests such as ASTM E108 for external fire, IEC for electrical safety of photovoltaic modules, and ASTM D3161 for wind resistance of shingles. No comprehensive standard existed to cover the wide range of performance characteristics needed in order for these roof covers to function satisfactorily. SPEAKERS MICHAEL C. BURKE FM APPROVALS MICHAEL C. BURKE graduated from Purdue University with a bachelor s degree in mechanical engineering. Mr. Burke spent several years in the construction industry before arriving at FM Approvals in He is an approvals engineer, evaluating a broad range of building materials, with a focus on roofing products. He is the primary author of the FM Approvals Standard for vegetative roof systems. JILL E. NORCOTT, PE FM APPROVALS JILL E. NORCOTT graduated from Worcester Polytechnic Institute with a master s degree in fire protection engineering. Shortly after, she joined FM Approvals as an engineer working primarily in the area of roofing materials. Ms. Norcott has gone on to become a technical team manager; she is responsible for the test facilities in West Glocester, RI, where all of the testing is conducted for the FM Approvals Materials Group. Ms. Norcott has been integral in the research and development of the Approval Standard for Photovoltaic Modules. 3 8 A L V E S, B U R K E, A N D N O R C O T T 2 6 T H R C I I N T E R N A T I O N A L C O N V E N T I O N A N D T R A D E S H O W A P R I L 7 1 2,

3 THE DEVELOPMENT OF FM APPROVAL STANDARDS FOR CLASS ONE STEEP ROOF COVERS, FLEXIBLE PHOTOVOLTAIC MODULES, AND VEGETATIVE ROOF SYSTEMS INTRODUCTION FM Approval Standards 4475, Steep Slope Roof Covers; 4476, Flexible Photovoltaic Modules; and 4477, Vegetative Roofs, are the first comprehensive standards to evaluate steep-slope roof covers (including rigid roofing in the form of shingles), flexible photovoltaic modules, and vegetative roofs. Failures of these types of roof coverings can occur as a result of highwind events and hailstorms as well as exposure to fire from above and below the roof deck. The test requirements in each standard are dependent upon the type of roof cover but include tests for wind, fire, hail, and water leakage. Current industry practice for evaluation of these types of systems is generally limited to individual performance tests such as ASTM E108 for external fire, IEC for electrical safety of photovoltaic modules, or ASTM D7158 or D3161 for wind resistance of shingles. No comprehensive standards existed to cover the wide range of performance characteristics needed in order to verify that these roof cover systems function satisfactorily. This paper will outline each test standard, including the research conducted to develop some of the pass/fail criteria. FM APPROVAL STANDARD 4475 (STEEP SLOPE ROOF COVERS) FM Approval Standard 4475 outlines the performance requirements for steepslope roof covers, which can be supplied in several forms, including self-sealing, interlocking (T-lock), slate, metal shingles, and polymer shingles. They are fabricated as single or multiple units that are joined together. Steep-slope roofing materials may be installed in either overlapping rows or courses with the fastened edge concealed from exposure to the weather. Internal fire, hail resistance, and wind resistance research testing were conducted on various steep-slope roof samples. The details of these tests are outlined in the following sections. Internal Fire Performance The fire tests from below the roof deck were conducted using the FM Approvals Construction Materials Calorimeter (NFPA 276). The tests were conducted in accordance with FM Approvals Standard The calorimeter fire test used in FM Approvals Standard 4475 is identical to that used in FM This test measures the maximum rate of fuel contribution by the roof sample, also expressed as maximum heat release rate (HRR); e.g., for a Class 1 rating, the assembly must exhibit a HRR no greater than 410 Btu/ft 2 /min (77.6 kw/m 2 ) in any three-minute time frame during the 30-minute fire exposure. Typically, if a low-slope roof assembly (for example, insulation and cover) meets the internal fire requirements over a steel deck, it will also meet the requirements over an FM-Approved wood deck. In the case of asphalt shingles, it was uncertain if these materials, applied directly to underlayment over an FM-Approved wood deck, would be able to pass the test criteria. Research testing of fiberglass-reinforced asphalt shingles was performed at FM Global s Research Campus in West Glocester, RI. It was determined that the asphalt shingles could pass the internal fire requirements of the test standard. Construction Materials Calorimeter Test Procedure The testing was performed on two different-weight, self-sealing, fiberglass-reinforced, granule-surfaced, laminated asphalt strip shingles. The shingles tested were architectural style with nominal weights of 245 lbs/sq (12 kg/m 2 ) and 310 lbs/sq (15 kg/m 2 ), respectively. The shingles were tested for 30 minutes using the principle of direct fuel substitution in which evaluating fuel at a metered rate is introduced to replace fuel contributed by the burning sample. The test procedure is accomplished in two steps: fire exposure and fuel evaluation. Testing was performed over wood decks. Both weight shingles were tested separately over FM-Approved nominal 2-in (51-mm) thick, FM-Approved, fire-treated lumber and three-quarter-inch (19-mm) thick, FM- Approved, fire-treated plywood. The lumber decks consisted of nominal 2x4 dimensional lumber, which was pressure-fit lengthwise in the test frame. The plywood was installed in two pieces with a center joint lying in the 5-ft (1.5-m) direction. Neither sample was constructed with additional bracing, and the samples were not conditioned to promote self-sealing. The decks were covered with one layer of ASTM D2178, Type-IV fiberglass felt or 15 lb/sq (0.7 kg/m 2 ) organic felt prior to the shingles being installed. The shingles were fastened to the deck with standard 1.5-in (38-mm) long roofing nails. Calorimeter Test Conclusions All samples met the Class 1 criteria by a significant margin, indicating good internal fire performance can be achieved with the current technology. The calorimeter tests showed that the test panels have fuel contribution rates of approximately half the maximum permissible rates for Class 1 construction. The lumber samples performed well with a maximum char thickness of approximately 1.5 in (38 mm). The remaining one-half inch (13 mm) of fire-treated decking reduced the above-deck components exposure to fire. As expected, the ¾- in (19-mm) thick plywood decks were less fire resistant than the nominal 2-in (51- mm) thick lumber decks. Wind Uplift Performance The wind resistance testing is conducted in accordance with ASTM D316, Standard Test Method for Wind Resistance of Asphalt Shingles (Fan Induced Method). After completion of this test, the manufacturer has the option of increasing the wind speed in 10-mph (4-m/s) increments four times, or until failure occurs. Successful completion of the test at the two-hour mark 2 6 T H R C I I N T E R N A T I O N A L C O N V E N T I O N A N D T R A D E S H O W A P R I L 7 1 2, A L V E S, B U R K E, A N D N O R C O T T 3 9

4 Figure 1 Example of shingle sample prepared for wind uplift resistance testing. satisfies the requirements of the Class F, Type I or II ASTM D b standard test. Continuing the test allows the manufacturer to obtain an FM Approvals Equivalent Wind Speed Rating. A 20-mph (9-m/s) safety factor is placed on the highest wind speed held. That is, a shingle that held at 120 mph (54 m/s) would be FM-Approved for use in a design wind speed area of 100 mph (45 m/s). See Figure 1. The wind uplift resistance testing was performed on the same type of shingles used in the calorimeter tests. The label of the 245 lbs/sq (12 kg/m 2 ) shingle indicated a wind warranty of 70 mph (31 m/s). The label of the 310-lbs/sq (15-kg/m 2 ) shingle indicated a wind warranty of 110 mph (49 m/s). Both shingles wrappers indicated that the shingles had passed ASTM D7158 Class H. Test Method #1: the shingles were tested in accordance with ASTM D3161 (a wind speed of 110 mph [49 m/s]) continuously for two hours. Following completion of this portion of the test, the wind speed was increased to 120 mph (54 m/s) for a 10- minute duration and continued in 10-mph (4-m/s) increments for 10-minute durations up to 160 mph (72 m/s). Test Method #2: the tests were conducted without the initial two-hour increment. This series began at 110 mph (49 m/s) but tested for a period of 10 minutes and increased in 10-mph (4-m/s) increments for 10-minute durations. The shingles were observed for signs of lifting off of the surface of the sample. Failure was deemed to have occurred when the shingle stood upright or folded back on itself. Sample Construction and Test Results The test samples were constructed in accordance with the manufacturer s specifications and conditioned in accordance with ASTM D3161, Standard Test Method for Wind Resistance of Asphalt Shingles (Fan Induced Method). All samples incorporated ASTM D2178, Type-IV fiberglass felts installed over the plywood deck prior to installation of the shingles The shingles were fastened to the deck following the manufacturer s High Wind Zone nailing pattern recommendation of six nails per 36-15/16-in (937-mm) shingle. 245 LBS/SQ (12 KG/M 2 ) SHINGLE Test Method #1 The sample was tested for a continuous two hours at a velocity of 110 mph (49 m/s) without failure. The sample passed the 10- minute mark at 120 mph (54 m/s) and eventually failed after 60 seconds at 130 mph (58 m/s). The failure occurred in the fourth row of shingles. The corner of the full shingle in this row had begun to lift after 33 minutes at 110 mph (49 m/s) but did not stand completely upright until exposed to the 130 mph (210 m/s) wind. Total test duration: 2 hours, 11 minutes. Successful 120-mph (54-m/s) velocity. Wind classification: 100 mph. Test Method #2 The sample was tested at 110 mph (49 m/s) for a period of 10 minutes and increased in 10-mph (4 m/s) increments for 10-minute durations. The sample passed the 150 mph (67 m/s) wind velocity test. No shingles were observed lifting during the test. Total test duration: 50 minutes. Successful 150-mph (67-m/s) velocity. Wind classification: 130 mph. 310 LBS/SQ (15 KG/M 2 ) SHINGLE Test Method #1 Upon reaching the 110-mph (49-m/s) velocity, the second row of shingles failed by standing upright. To continue with the research, the second row was face-nailed. The third row is the target row, according to the ASTM Standard. At four minutes and 30 seconds, a shingle corner in row seven lifted approx. ½ in (13 mm). At seven minutes, a shingle corner in row 12 lifted approximately ½ in (13 mm). At 12 minutes, a shingle corner in row six lifted approximately ¾ in (19 mm). At one hour and 20 minutes, the corner of a shingle in row four lifted approximately ¾ in (19 mm). The testing continued for the full two hours with additional slight lifting of the shingles noted above. The testing continued to the 120- mph (54-m/s) velocity and failed after five minutes when a shingle in row four stood upright. Total test duration: 2 hours, 5 minutes. Failed to meet the 110-mph (49-m/s) minimum rating. Test Method #2 The sample was tested at 110 mph (49 m/s) for a period of 10 minutes and increased in 10-mph (4-m/s) increments for 10-minute durations. At 130 mph (58 m/s), the corner of a shingle in row five lifted 1½ in (38 mm) after approximately three minutes of exposure. There was no change in the sample through the 140-mph (63-m/s) test velocity. The test apparatus failed during the 150-mph (67-m/s) velocity test. Total test duration: 40 minutes. Successful 140-mph (63-m/s) velocity. Wind classification = 120 mph. Wind Uplift Test Conclusions The heavier shingle did not demonstrate better test performance than the lighter shingle. The longer duration tests achieved lower wind classifications than the shorter duration tests. It appeared that prolonged exposure (2 hours +) to constant high winds (110 mph [49 m/s]) had more of an effect on the shingles than increased velocities (> 110 mph [49 m/s]) for shorter exposure periods. Shingle substrates other than FM- Approved wood decks will be evaluated for resistance to wind uplift loads via the FM Approvals uplift pressure apparatus in accordance with FM Approvals Standard Hail Damage Resistance Performance Simulated hail testing was performed on architectural-style, asphalt-laminated roof shingles to compare two different testing methods. The two methods are currently used in the rating of roof shingles for Class 4 (severe) service. One method utilizes steel balls of a prescribed weight and size, dropped from a specific distance onto a sample deck. The second method utilizes ice balls of a prescribed weight and size, shot toward the sample by a mechanical apparatus at a prescribed velocity. Testing was conducted to determine if the two test methods would yield similar results. Sample Construction The sample deck for each test method utilized a 3x3-ft (0.9x0.9-m) surface area of 15/32-in (12-mm) thick plywood nailed to a 4 0 A L V E S, B U R K E, A N D N O R C O T T 2 6 T H R C I I N T E R N A T I O N A L C O N V E N T I O N A N D T R A D E S H O W A P R I L 7 1 2,

5 frame constructed of nominal 2x4-in (51x102-mm) lumber, including a midspan vertical support. No underlayment was used. Mineral-surfaced, fiberglass-reinforced asphalt shingles with a nominal weight of 300 lb/sq (15 kg/m 2 ) were installed. The shingles were a laminated product with a traditional single-tab design making up the bottom surface, laminated along the nail line to a top piece, with cutouts exposing the bottom surface at various intervals. The result is a strip type shingle that gives the appearance of individually attached shingles. In accordance with the test methodology, both samples were conditioned for a period of approximately 16 hours at a slope of 2 in 12 and at a constant temperature of 135 F to 140 F (57 C to 60 C). The samples were allowed to cool to room temperature prior to testing. Ice Ball Hail Test Method The Class 4 ice ball hail test was conducted in accordance with FM Approval Standard 4473, Specification Test Standard for Impact Resistance Testing of Rigid Roofing Materials by Impacting With Freezer Ice Balls. The hail test used in FM Approval Standard 4475 is identical to that used in FM Approval Standard Utilizing a spherical ice ball 2 in (51 mm) in diameter, weighing grams, and discharged at the target at velocity of 76.1 to 83.7 mph (34 to 37 m/s), the resultant kinetic energy must range from to ft-lbs (36.46 to N-m). The target and testing apparatus were aligned at an angle of 15 degrees off vertical and spaced 5 ft (1.5 m) apart. The ice ball impacts the sample at a 90-degree angle. Steel Ball Hail Test Method The Class 4 steel ball hail test utilizes a spherical steel ball 2 in (51 mm) in diameter and weighing ± 18 grams. The ball is dropped from a distance of 20 ft (6.1 m) through a 3-in (76-mm) diameter, schedule 40 PVC pipe. The resultant kinetic energy ranges from to ft-lbs (24.96 to N-m). The steel ball impacts the sample at a 90-degree angle. Each sample is impacted 12 times in areas not limited to an edge, corner, overlap, unsupported area, or joint between two shingle tabs. Each of the impact areas must be impacted twice with a maximum distance of ½ in (13 mm) between impact areas. The location must be a minimum of 6 in (152 mm) apart. For both the ice and steel samples, each of the target areas was impacted as specified, and the shingles were marked to identify the shot number prior to being removed from the deck. The individual shingles were removed and examined. The top and bottom surface of each shingle impacted were viewed under 5x magnification to determine any damage, including cracking, splits, fractures, breakage, and disengagement of lap elements as a result of the impact force. Hail Damage Resistance Conclusions Although both test methods resulted in failures, the ice ball hail test resulted in three failures versus a single failure with the steel ball hail test. The ice ball hail test is considered to be more critical for rigid test samples. In addition to the number of failures, the shingle failures utilizing the ice ball test were observed during the examination to be punctures visible to the naked eye, while the shingle failure utilizing steel balls was observed to be cracks, only visible under examination with 5x magnification. The general appearance of the bottom surface of the shingles tested with the ice balls differed from that tested with the steel balls. The impact points of the ice balls could be seen with the naked eye, due to the fact that the granules used as the surfacing appeared to have been pushed towards the bottom surface of the shingle impacted, giving a lighter appearance in the area of impact. FM APPROVAL STANDARD 4476 (FLEXIBLE PHOTOVOLTAIC MODULES) This standard applies to all flexible photovoltaic modules intended to be adhered to, or mechanically fastened through, an FM-Approved single-ply, polymer-modified bitumen sheet, built-up roof, liquid-applied, or standing-seam or metal roof cover assembly. This standard does not intend to qualify rigid photovoltaic modules that are mechanically fastened using clips or other types of fasteners through single-ply, polymer-modified bitumen sheet, built-up roof, liquid-applied roof systems, or to standingseam or metal roofs. Rigid photovoltaic systems are to be evaluated per FM Approval Standard Currently, both of these photovoltaic test standards are under development. FM Approval Standard 4476 evaluates flexible photovoltaic modules for combustibility from above the roof deck per ASTM E108, Standard Test Methods for Fire Tests of Roof Coverings; wind uplift resistance; hail damage resistance; electrical performance; electrical safety; and heataging effects. Combustibility from above the roof deck, wind uplift resistance, and hail damage resistance test procedures are based on existing FM Approval Standard Tests for combustibility from below the roof deck are not included in Approval Standard 4476 because the modules must be installed over a roof assembly that is FM- Approved per FM Approval Standard 4470 or At this time, there is no single standard available that includes testing for all of the criteria listed above. Most standards focus on the electrical performance and safety requirements of the module. FM Approvals developed a standard that also included natural hazards testing to reinforce the mission of avoiding property loss. Wind Uplift Resistance There are several different methods of testing flexible photovoltaic modules for wind uplift resistance. The method utilized is determined by the construction of the roof assembly (including the module) and the desired wind uplift rating. The minimum rating required for FM Approval is Class The maximum rating available is Class Ratings between 1-60 and are available in increments of 15 psf (0.72 kpa). The rating assigned to the combined photovoltaic/roof assembly shall be the maximum simulated uplift resistance pressure that the assembly maintains for one minute without failure. The maximum simulated uplift resistance pressure will be the minimum value from either of the required tests listed below. For modules that are adhered to a metal panel roof covering, the 12x24-ft (3.7 x7.3-m) Simulated Wind Uplift Pressure Test and 1x4-ft (0.3x1.2-m) Wind Uplift Test are used. These tests are run in accordance Figure 2 Flexible photovoltaic modules mounted to metal standingseam roof. 2 6 T H R C I I N T E R N A T I O N A L C O N V E N T I O N A N D T R A D E S H O W A P R I L 7 1 2, A L V E S, B U R K E, A N D N O R C O T T 4 1

6 with Test Procedure 12x24 ft Wind Uplift Tests for Standing Lap Seam and Composite Panel Roof Coverings, FM Approvals, LLC; and Test Procedure 1x4 ft Wind Uplift Test for Flexible Photovoltaic Modules Adhered to Standing Lap Seam and Composite Panel Roof Covers, FM Approvals, LLC, respectively. See Figure 2. During the 12x24-ft pressure test, the candidate photovoltaic roof assembly, comprising a specific combination of components, shall possess adequate physical properties to resist 1) a specified minimum uplift pressure without disengagement or fracture of any component and 2) half the specified minimum uplift pressure without any permanent deformation of any component. (Prior to catastrophic sample failure, the wind uplift pressure at which permanent deformation occurs will be noted. As FM wind uplift design pressure recommendations are based on a factor of safety of 2, the maximum wind uplift rating that will be allowed will be twice the pressure of permanent deformation, even if catastrophic failure does not occur.) Any separation, permanent deformation, withdrawal, or fracture within the photovoltaic roof assembly (including the photovoltaic module) is therefore considered a failure. After the 12x24-ft test, the photovoltaic module is subjected to the 1x4-ft wind uplift test. The tests are conducted on the same roof assembly to ensure that the panels and modules experience the stresses that may occur during a wind event. During the 1- x 4-ft test, all photovoltaic modules and/or membranes shall not delaminate or separate from adjacent components and all adhesives shall maintain full contact between the surfaces of all components to which they have been applied or with which they come in contact, without any separation, delamination, fracture, cracking, or peeling of the adhesive or its bonds. For all other constructions, the 5x9-ft Figure 3 Flexible photovoltaic modules adhered to single ply roof cover. 4 2 A L V E S, B U R K E, A N D N O R C O T T (1.5x2.7-m) Simulated Wind Uplift Pressure Test, 12 x 24 ft (3.7 m x 7.3 m) Simulated Wind Uplift Pressure Test, and Simulated Wind Uplift Pull Test are used for testing the photovoltaic roof assembly. All of these tests are conducted in accordance with ANSI/FM Approvals 4474, Evaluating the Simulated Wind Uplift Resistance of Roof Assemblies Using Static Positive and/or Negative Differential Pressures. See Figure 3. The 5x9-ft (1.5x2.7-m) simulated wind uplift pressure test procedure is used to determine the simulated wind uplift resistance of the following types of roof assemblies (because of the edge effects created when testing this size roof sample, the maximum wind uplift rating for the 5x9 test is Class 1-90): Assemblies that utilize mechanical fasteners, adhesives, hot asphalt, heat welding, self-adhesive components or any combination thereof to secure insulations; a base ply, plies, or a cap ply sheet; exterior coverings and other components, in single or multilayered constructions to one another and to the roof deck. Adhesive securement to steel roof deck is not permitted. Assemblies that utilize air-pervious decks to include cementitious wood fiber, steel, wood, or fiber-reinforced plastic roof decks. Assemblies with mechanically secured roof covers with securement row spacing less than or equal to 48 in (1220 mm) on center with maximum in-row spacing of 24 in (610 mm). Assemblies with mechanically secured roof covers with securements (spot or grid affixed) spacing less than or equal to 24x48 in (610x1220 mm) on center. Assemblies with mechanically secured insulation (maximum 48x96-in [1220x2440-mm] board) with a maximum contributory securement area of 5.33 ft 2 (0.50 m 2 ) per fastener, e.g., six fasteners on a 48x96-in (1220x2440-mm) board size. The 12x24-ft (3.7x7.3-m) simulated wind uplift pressure test procedure is to be used to determine the simulated wind uplift resistance of the types of roof assemblies listed below. (There is no limit for the wind uplift rating when testing this size sample. Currently, there are FM-Approved roof assemblies with ratings as high as Class ) Assemblies other than those evaluated via the uplift pull test or 5x9-ft uplift pressure test. Assemblies that utilize mechanical fasteners, adhesives, hot asphalt, heat welding, or a combination thereof, to secure the flexible photovoltaic module to the roof cover or to the roof deck. Assemblies that utilize batten bars or rows of fasteners spaced less than or equal to 144 in (3660 mm) on center with maximum in-row spacing of 48 in (1220 mm). The conditions of acceptance for both the 5x9-ft and 12x24-ft simulated wind uplift pressure tests are identical and are identified below: All fasteners and stress plates shall 1) remain securely embedded into or through roof decks and other structural substrates to which they are being fastened to or through; 2) not pull through, become dislodged, disconnected or disengaged from plates, battens, seams or substrates; c) not fracture, separate or break. All insulations shall 1) not fracture, break, or pull through or over, fastener heads, plates, or battens; 2) not delaminate or separate from their facers or adjacent components to which they have been adhered; 3) be permitted to deflect between points of mechanical securement, provided that the insulation boards do not fracture, crack, or break. All membranes or photovoltaic modules shall 1) not tear, puncture, fracture, or develop any through openings; 2) not delaminate or separate from adjacent components. Exceptions: 1) Mechanically fastened membranes shall be permitted to separate and deflect from adjacent components at locations where they are not fastened, and 2) partially adhered membranes shall be permitted to separate and deflect from adjacent components at locations where adhesive placement was not intended. All adhesives shall maintain full contact among all the surfaces of all components to which they have been applied or with which they 2 6 T H R C I I N T E R N A T I O N A L C O N V E N T I O N A N D T R A D E S H O W A P R I L 7 1 2,

7 have come in contact, without any separation, delamination, fracture, cracking, or peeling of the adhesives or their bonds. All roof decks shall 1) maintain their structural integrity during the entire classification period; 2) not fracture, split, crack, or allow for fastener withdrawal Stresses induced to steel roof decking shall be determined by rational analysis and shall not exceed the allowable stresses per the latest edition of the American Iron and Steel Institute Cold Formed Steel Design Manual. All other components, including photovoltaic modules, seams, base sheets, base plies, plies, and cap plies shall not tear, puncture, fracture, disengage, dislodge, disconnect, delaminate, or develop any through openings. The simulated wind uplift pull test is a 2x2-ft test that shall be used to evaluate partially or fully adhered photovoltaic modules used with the following types of assemblies: Assemblies with components (cover board, insulation, vapor retarder) either partially or fully adhered to monolithic structural concrete roof decks or gypsum or lightweight concrete cast over monolithic structural concrete. When substrates are partially adhered in ribbons, the adhesive is applied in rows spaced less than or equal to 12 in (305 mm) on center. Assemblies where the single-ply roof cover is fully adhered to a cover board, insulation, or deck. Assemblies where the multi-ply roof cover is partially adhered to a cover board, insulation, or deck. Assemblies with a perforated base sheet partially adhered to an insulation or deck and with a rigid insulation adhered above the perforated base sheet. Assemblies with a maximum rigid insulation board size of 48x48 in (1220x1220 mm). The conditions of acceptance for the simulated wind uplift pull test are as follows: All insulations and photovoltaic modules shall 1) not fracture or break; 2) not delaminate or separate from their facers or adjacent components to which they have been adhered. All photovoltaic modules and/or membranes shall not delaminate or separate from adjacent components. All adhesive shall maintain full contact between all the surfaces of all components to which it has been applied or with which it comes in contact, without any separation, delamination, fracturing, cracking, or peeling of the adhesive or its bond. All other components, including seams, vapor retarders, and base or ply sheets shall not tear, puncture, fracture, disengage, dislodge, disconnect, delaminate, or develop any through openings. Hail Damage Resistance Testing for hail damage resistance shall be in accordance with Test Procedure, Test Method for Determining the Susceptibility to Hail Damage of Photovoltaic Modules, FM Approvals, LLC. There are two ratings available for approval: moderate hail (MH) and severe hail (SH). The desired rating is identified by the test sponsor. Both the moderate and severe test methods are based on the test methods utilized for Approval Standard Approval Standard 4470 test methods are utilized because we are testing a flexible photovoltaic module where steel hail balls were determined to be most critical, as opposed to ice hail balls utilized in Approval Standard One sample is subjected to ultraviolet (UV) conditioning, and the second sample remains unconditioned. After conditioning as needed, both samples are tested in accordance with the test procedure. For moderate testing, a 2-in- (51-mm-) diameter steel ball weighing 1.19 lb (540 g) is dropped from a height of 81 in (2055 mm) onto the sample. This procedure generates an impact energy of approximately 8 ft lb (10.8 J) over the impact area of the 2-in- (51-mm-) diameter ball. For severe testing, a 2-in- (51-mm-) diameter steel ball weighing 1.19 lb (540 g) is dropped from a height of in (3595 mm) onto the sample. This procedure generates an impact energy of approximately 14 ft lb (19 J) over the impact area of the 2-in- (51-mm-) diameter ball. The module cannot show signs of cracking or splitting. Under adhered conditions, minor separation of the module from the roof cover or the roof cover from the substrate (directly under the impact area) is acceptable for monolithic decks only (i.e., structural concrete, lightweight insulating concrete, or gypsum) under 10x magnification. Electrical Performance Testing for electrical performance shall be in accordance with Thin Film Terrestrial Photovoltaic (PV) Modules Design Qualification and Type Approval, International Standard IEC/EN 61646, International Electrotechnical Commission/European Norm. After review of the existing international standards for electrical performance, FM Approvals believes that IEC/EN is the most comprehensive. A majority of photovoltaic manufacturers have already tested their products to this standard and are familiar with the test requirements. A test sample must meet all test requirements in IEC/EN except the Hail Test, Test FM Approvals is confident that the hail damage resistance test that is currently in use for FM-Approved roof covers is more severe than the hail test outlined in IEC/EN Electrical Safety Testing for electrical safety shall be in accordance with Photovoltaic (PV) Module Safety Qualification Part 2: Requirements for Testing, International Standard IEC/EN , International Electrotechnical Commission/European Norm. After review of the existing international standards for electrical safety, FM Approvals believes that IEC/EN is the most comprehensive. A majority of photovoltaic manufacturers have already tested their product to this standard and are familiar with the test requirements. A test sample must meet all test requirements in IEC/EN except the Fire Test, MST 23. FM Approvals is confident that the ASTM E108 test procedure is a more severe fire test than MST 23. Heat Aging Effects of the Roof Cover Under the Photovoltaic Module Testing for effects of heat aging from photovoltaic modules applied to a roof cover shall be in accordance with FM Approvals Test Procedure Tests for Measuring Heat Aging Effects of Flexible Photovoltaic Modules on Roof Coverings. There is a concern that the photovoltaic module may negatively affect the durability of a roof cover, especially light-colored covers, because the 2 6 T H R C I I N T E R N A T I O N A L C O N V E N T I O N A N D T R A D E S H O W A P R I L 7 1 2, A L V E S, B U R K E, A N D N O R C O T T 4 3

8 module will cause the underlying membrane to reach temperatures higher than normally experienced. In order to determine the effect of the photovoltaic module on the roof cover, the roof membrane will have to be tested under high-heat conditions. FM APPROVAL STANDARD 4477 (VEGETATIVE ROOF SYSTEMS) This standard applies to all vegetative roof systems that are intended to be installed over an FM-Approved single-ply, polymer-modified bitumen sheet, built-up roof, or liquid-applied roof cover assembly. The roof cover assembly over which the vegetative roof system is installed shall meet the requirements of Approval Standard 4470 with the exception of UV conditioning, susceptibility from hailstorm damage and performance in regard to fire from above the deck. However, any portion of the single-ply, polymer-modified bitumen sheet, built-up roof, and liquid-applied roof cover system that is not covered by the vegetative roof systems (for example, vertical flashing at a parapet wall, where the membrane extends above the growth media) shall be qualified in accordance with all requirements of Approval Standard The standard is intended to evaluate only those hazards investigated and is not intended to determine suitability for the end use of a product. This standard evaluates vegetative roof systems for their performance in regard to combustibility from above and below the structural deck, foot traffic, and water leakage. Combustibility from above and below the roof deck, foot traffic, and water leakage test procedures are based on existing FM Approval Standard 4470 test procedures. Installation of the above-roof cover components (the vegetative roof system) shall be in accordance with FM Global Property Loss Prevention Data Sheet Green Roof Systems. Sample No. Slope Class Tested Table 1 Max. Flame Spread Class Passed 1 2 in 12 A 3 ft 4 in (1.02 m) A 2 2 in 12 A 3 ft 5 in (1.04 m) A 3 3 in 12 A 3 ft 5 in (1.04 m) A 4 3 in 12 A 3 ft 5 in (1.04 m) A Fire Tests of Roof Coverings, ASTM E108, ASTM International. The ASTM E108 fire test used in FM Approvals Standard 4477 (Approval Standard for Vegetative Roof Systems) is identical to that used in FM Approvals Standard This test measures the flame spread of a roof assembly when subjected to an external fire source. No standard currently exists that requires testing of vegetative roof systems for external spread of flame, although some standards specify design standards with external spread of flame in mind. In the development of this standard, fire testing was performed over sedum vegetation, a popular vegetation used for vegetative roof systems. A wide range of sedum vegetation was tested. Research testing of vegetative roof systems was performed at the FM Global Research Campus in West Glocester, RI. It was determined that the vegetation would be most critical in flame spread following a period of drought when most of the moisture had migrated out of the plant material. The samples that were tested were not watered for a period of four weeks prior to testing. Some samples were left in direct late-august sunlight, while other samples were kept indoors out of the sunlight altogether. The test samples consisted of several modular-type trays placed together on a standard ASTM E108 plywood test deck. The trays exhibited a 100% coverage of vegetation. The trays themselves were subterranean and not exposed directly to the external flame source. ASTM E108 Results Testing was performed on four samples. The maximum spread of flame over the 10- minute test duration is shown in Table 1. Combustibility From Above the Roof Deck The fire tests from above the roof deck were conducted using the ASTM E108 test apparatus. The tests were conducted in accordance with Figure 4 ASTM E108 sample on the test apparatus during combustibility test. 4 4 A L V E S, B U R K E, A N D N O R C O T T 2 6 T H R C I I N T E R N A T I O N A L C O N V E N T I O N A N D T R A D E S H O W A P R I L 7 1 2,

9 son, recover constructions over existing FM-Approved Class 1 roof decks are limited to 1 in [25 mm] of insulation, unless otherwise tested.) Therefore, the entire assembly, including the vegetative roof components, will be tested for interior combustibility. The vegetative roof system manufacturer will specify the FM-Approved assemblies that will be incorporated into the calorimeter tests. The test panels are required to maintain fuel contribution rates below the maximum permissible rates for Class 1 constructions. These rates and the Class 1 limits are noted in Table 2. Figure 5 Vegetative roof after ASTM E108 testing. ASTM E108 Conclusions The samples tested did not burn more than inches ( mm), and the lateral spread was not significant. There were some glowing embers emitted during testing, but they did not sustain a glow and were extinguished before reaching the floor. Under these conditions, the samples passed Class A ratings for slopes of 2 in 12 and 3 in 12. The FM Approval Standard 4477 will still require ASTM E108 testing; however, this test data developed by FM will be available to customers for their use on similar plant products in order to waive testing. The standard also allows for external fire testing of system products other than vegetation. In some cases, the finished roof assembly may include additional items in conjunction with the vegetation, such as wind blankets and trays. FM Approvals may require that these items be tested as part of the finished roof assembly, even if these items are specified by the manufacturer to be temporary. Combustibility From Below the Roof Deck The fire tests from below the roof deck were conducted using the FM Approvals Construction Materials Calorimeter. Testing was conducted in accordance with FM Approval Standard The calorimeter fire test used in FM Approval Standard 4477 (Approval Standard for Vegetative 2 6 T H R C I I N T E R N AT I O N A L C O N V E N T I O N AND Roof Systems) is identical to that used in FM Approval Standard This test measures the maximum rate of fuel contribution by the sample roof, also expressed as maximum heat release rate (HRR); e.g, for a Class 1 rating, the assembly must exhibit a HRR no greater than 410 Btu/ft2/min (77.6 kw/m2) in any three-minute time frame during the 30-minute fire exposure. As stated above, the vegetative roof system must be installed over an FM-Approved single-ply, polymer-modified bitumen sheet, built-up roof, or liquid-applied roof cover assembly. Although this FM-Approved assembly must have a Class 1 rating over combustible deck, the addition of the vegetative roof system on top of the FMApproved assembly may change the rating of the system. The FM-Approved roof deck assembly may be a Class 1 system, but, by adding vegetative roof components; more heat and combustible gases may be liberated by the Class 1 roof deck. (For this rea- Foot Traffic Testing for foot traffic resistance of the drainage/ retention panel shall be in accordance with Test Procedure, Test Method for Determining the Foot Traffic Resistance of Roof Coverings, FM Approvals, LLC. The vegetative roof system will be subject to foot traffic during and following installation. The foot traffic resistance test is to verify the ability of the vegetative roof system components to resist foot traffic. While not intended for the FM-Approved roof cover layer, which will already have been evaluated per FM 4470, it is intended to verify the ability of the vegetative roof assembly components to withstand foot traffic during and after installation, primarily the water retention layer to retain its ability to hold water as a source of hydration for vegetation as recommended by FM Global Property Loss Prevention Data Sheet Green Roof Systems. In the case of interlocking tray systems, the tested layer may be the tray itself. The test sample shall have no signs of tearing or cracking of any vegetative roof Maximum Average Rate of Fuel Contribution for Various Time Intervals Btu/ft2/min (kw/m2) Time Interval Class 1 Standard Table 2 TRADE SHOW 3 min 410 (77.6) APRIL 7 12, min 390 (73.8) 10 min 360 (68.1) A LV E S, B U R K E, AND Average 285 (53.9) NORCOTT 45

10 system components causing one component to introduce itself into the another component layer due the material failure of any one layer. Water Leakage Testing for water leakage resistance of the root barrier shall be in accordance with Standard Test Method for Determining Water Migration Resistance Through Roof Membranes, ASTM D7281, ASTM International. While not intended for the FM-Approved waterproofing membrane of the roof cover layer, it is intended to verify the performance of a monolithic root barrier layer in the vegetative roof assembly as recommended by FM Global Property Loss Prevention Data Sheet 1-35, Green Roof Systems. There shall be no signs of water leakage during the seven-day period. In addition, there shall be no signs of water leakage during or after the pressure cycles. Wind Uplift Resistance Installation of the above-roof cover components (the vegetative roof system) shall be in accordance with FM Global Property Loss Prevention Data Sheet 1-35, Green Roof Systems. As stated above, the roof cover assembly over which the vegetative roof system is installed shall meet the requirements of FM Approval Standard 4470, with the exception of UV conditioning, susceptibility from hailstorm damage, susceptibility to foot traffic damage, and performance in regard to fire from above the deck. Any portion of the single-ply, polymermodified bitumen sheet, built-up roof, and liquid-applied roof cover systems that is not covered by the vegetative roof system shall be qualified in accordance with all requirements of FM Approval Standard CONCLUSIONS FM Approval Standards 4475 (Steep Slope Roof Covers), 4476 (Flexible Photovoltaic Modules), and 4477 (Vegetative Roofs) are the first comprehensive standards to evaluate steep-slope roof covers (including rigid roofing in the form of shingles), flexible photovoltaic modules, and vegetative roofs. Prior to the development of these standards, no comprehensive standards existed to cover the wide range of performance characteristics needed in order to verify the performance of these roof cover systems. Significant time has been spent on the research and development of these standards to ensure that they include testing for the potential failure modes for these types of roof cover systems. FM Approvals is confident that these new standards will help prevent property loss. 4 6 A L V E S, B U R K E, A N D N O R C O T T 2 6 T H R C I I N T E R N A T I O N A L C O N V E N T I O N A N D T R A D E S H O W A P R I L 7 1 2,