NCDOI OSFM Evaluation Services Scope of DOI White Paper: The Purpose of this document is to provide clarification and suggested best practices on North Carolina State Code requirements to Code Enforcement Officials (CEO) who are agents for the Authority Having Jurisdiction (AHJ). DOI File Number: WP-002-10 Edition Date: June 9, 2010 Revision Date: May 20, 2013

Subject of White Paper: Protection of Exterior Openings in Wind-Borne Debris Regions Table of Contents 1.0 Intent…………………………………………………………………………………………………....1 2.0 Scope of the NCRC and the NCBC and Definition of “Wind-Borne Debris Region”………...…….…2 3.0 Why Codes Require Openings in the Exterior Envelope of Buildings to Withstand Hurricane Force Winds…………………………………………………………………………………………….……3 4.0 Code Options for Protecting Glazing in Exterior Openings Located in a Wind-borne Debris Region...4 5.0 Code Requirements for Impact-Resistant Glazing and for Coverings to Protect Non-Impact-Resistant Glazing in Windows, Doors, and Garage Doors……………………………………………………...5 6.0 Code Requirements for Wood Structural Panels……………………………………………………….7 7.0 Code Design Requirements for Exterior Window, Door, and Garage Door Assemblies to Resist Wind Pressure………………………………………………………………………………………………..7 8.0 Basic Description of ASTM E 1886 and ASTM E 1996…………………………….………..…….....8 9.0 NCRC Code Requirements when Replacing Windows in Existing Residential Dwellings Located in a Wind-Borne Debris Region…………………………………………………………………………...9 10.0 Submittals the Code Enforcement Official may request for Verification of Code Compliance or Equivalency………………………………………………………………………………………….10 11.0 Maintaining Emergency Escape and Rescue Opening Code Requirements in Wind-borne Debris Regions………………………………………………………………………………………………12 12.0 Recommendations for Job Site Consideration by the Code Enforcement Official..............................13 13.0 Other Recommendations for Consideration by the Code Enforcement Official……………………..13 14.0 References…………………………………………………………………………………………….14 15.0 Credits for Figures……………………………………………………………………………………14 16.0 Illustrations Attached to this Document……………………………………………………………...15 1.0

Intent A. The 2012 North Carolina Residential Code (NCRC) and the 2012 North Carolina Building Code (NCBC) each have similar requirements for protecting openings in the exterior envelope of a building located in a wind-borne debris region*. The intent is to keep the glazing in these openings (windows, doors and garage doors) from being breached when impacted by debris propelled by hurricane-force winds, as well as from the resulting wind pressure to these

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opening assemblies. * Section 2.0 of this document addresses the scope of the NCRC & the NCBC and their definition of “wind-borne debris region”. B. Note the following for clarification:

2.0

1.

Code requirements for impact protection of glazing apply to glass in exterior openings of buildings that are only located in a wind-borne debris region. Glazing protection is not required by code in exterior openings located in non-wind-borne debris regions, except as addressed in Section 2406 of the NCBC.

2.

Code requirements for the design pressure rating, often referred to as the “DP” rating”, of exterior window and door assemblies shall be in accordance with the wind zone of buildings located throughout the state and not only for buildings located a wind-borne debris region.

Scope of the NCRC and the NCBC and Definition of “Wind-Borne Debris Region” A. NCRC: 1.

The scope of the NCRC is addressed in R101.2. This section states this code “shall apply to the construction, alteration, movement, enlargement, replacement, repair, equipment, use and occupancy, location, removal and demolition of detached one- and two-family dwellings and townhouses not more than three stories above grade plane in height with a separate means of egress and their accessory buildings and structures”.

2.

Basic (design) wind speeds for 50 year mean recurrence interval for NC Counties are determined from the map in Figure R301.2 (4) and interpolation between contours on the map is not allowed. There is a chart, also identified as “Figure R301.1(4)-continued”, which specifically lists the design wind speed for each N. C. County.

3.

Section R202 of the NCRC defines “wind-borne debris region” as follows: WIND-BORNE DEBRIS REGION-Areas within hurricane prone regions defined as that area east of the inland water-way from the North Carolina/South Carolina state line north to Beaufort Inlet and from that point to include the barrier islands to the North Carolina/Virginia state line.

B. NCBC: 1.

The NCBC is applicable to all structures that are not regulated by the NCRC, as addressed in Section 101.2 of the NCBC. Note that detached one & two family dwellings and multiple single family dwellings (townhouses) that are more than three stories above grade plane in height are classified by occupancy as R-3 and shall comply with the requirements of the NCBC.

2.

The basic wind speed to determine the wind loads for NC Counties is indicated on the map in Figure 1609 and is in 10 mile per hour increments. Interpolation between contours on the map is allowed.

3.

Section 1609.2 of the NCBC defines “wind-borne debris region” as follows: WIND-BORNE DEBRIS REGION-Areas within hurricane prone regions defined as that area east of the Intracoastal water-way from the North Carolina/South Carolina state line north to Beaufort Inlet and from that point to include the barrier islands to the North Carolina/Virginia state line.

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3.0

Why Codes Require Openings in the Exterior Envelope of Buildings to Withstand Hurricane Force Winds A. The NCRC and the NCBC require the structure of a building located in a wind-borne debris region to withstand sustained hurricane-force winds flowing around and over its exterior envelope. Each Code also requires the opening assemblies located in the exterior of the building envelope to withstand the pressures from high winds and the glazing in these openings to remain in place when subjected to objects propelled by high winds. B. Depending on the location of opening(s) with respect to wind direction during a hurricane, breached openings in the exterior envelope can allow strong winds to rush inside the building. These trapped wind forces can create extremely high internal pressures on the roof, sidewalls and leeward wall that exceed the resistant limitation of the building’s structural elements to withstand the total wind pressure. Consequently, the internal pressures can ultimately result in severe damage to, if not total destruction of, the building. An elementary example of this effect is to pump air into a tire until the outer surface, at its weakest point, blows out. (See figure 1)

Figure 1: Effects of internal pressure in the interior of a building from a breached opening in the exterior envelope during hurricane-force winds C. The NCBC and the NCRC address protection requirements for glazing and opening assemblies in the exterior envelope of a building located in a wind-borne debris region: 1.

Glazing: In exterior windows, doors, garage doors and similar openings, glazing is required to be protected from being shattered by wind-borne debris. Note that “windborne debris” can be any object or material that could become an air borne missile propelled by hurricane-force winds. For example, sustained hurricane-force winds can dislodge building materials, such as shingles or roofing gravel, or unsecured objects on the ground, such as trashcans or patio furniture. Thus, these objects can become “missiles”, which could break out the glass in an exterior opening. Impact resistance is required only in the wind-borne debris regions defined by the Code, except as addressed in Section 2406 of the NCBC. See Section 4.0 of this document for code options to protect glazing in exterior openings.

2.

Opening assemblies: When subjected to the forces and pressures of high wind, codes address the ability for exterior window, door, and garage door assemblies (sashes, frames, associated fasteners, etc.) to remain in place, i.e., to not be blown in or out. See Section

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7.0 of this document for information on code design requirements for window, door, and garage door assemblies to resist wind pressure. 4.0

Code Options for Protecting Glazing in Exterior Openings Located in a Wind-borne Debris Region The NCRC and NCBC require all glazing on the exterior of buildings located in wind-borne debris regions to be impact resistant or to be protected with an impact-resistant covering. Another option, which is a prescriptive code method, is to install wood structural panels over non-impact resistant glazing for protecting the glass from flying debris. A. Impact-Resistant Glazing: For a new building or an addition to an existing building located in a wind-borne debris region, impact-resistant glazing complying with code is an option to prevent an opening from being breached by flying debris (See Figure 2). Impactresistant glazing is composed of several layers of glass with a membrane film sandwiched between each layer. Although flying debris may be able to crack the glass, the intent is for the lamination to hold the broken layers of glass together to prevent the missile from penetrating the building envelope, and thus breaching the exterior opening. Refer to 5.0 of this document for NCRC and Figure 1: Impact resistant glass NCBC requirements for impact-resistant glazing systems. after being struck by 2 x 4 B. Protective Coverings for Non-Impact-Resistant Glazing: The NCRC and the NCBC have requirements for impact-resistant coverings to protect non-impact-resistant glazed openings in the exterior of a new building or an addition to an existing building located in wind-borne a debris region. 1.

Protective coverings can be made of wood, metal (aluminum, galvanized steel, stainless steel, etc.), fiberglass, flexible fabric/woven mesh screens, polycarbonate, polypropylene, (or similar plastic paneled systems) and other materials that have been tested to comply with impact-resistant requirements of the code.

2.

Some examples of covers that may provide protection for non-impact resistant glazing include roll down shutter systems (Figure 3), side-hinged shutters (Figure 4), horizontal sliding accordion shutter system (Figure 5 on page 5) and Bermuda/Bahamas style shutters (Figure 6 on page 5).

Figure 3: Example of roll-down shutter at head of windows.

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Figure 4: Example of side-hinged shutters on each side of window/door.

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Figure 5: Example of horizontal sliding accordian shutter system in the opened and in the closed positions.

3.

Figure 6: Example of Bahamas /Bermuda style shutters in the opened and in the closed positions.

Refer to 5.0 of this document for NCRC and NCBC requirements for coverings to protect non-impact-resistant glazing.

C. Wood Structural Panels: For a new building or an addition to an existing building located in a wind-borne debris region, wood structural panels installed over exterior non-impact resistant glazing is a prescriptive code method for protecting exterior glazed openings from flying debris. Refer to 6.0 of this document for NCRC and NCBC requirements for wood structural panels. 5.0

Code Requirements for Impact-Resistant Glazing and for Coverings to Protect Non-ImpactResistant Glazing in Windows, Doors, and Garage Doors A. NCRC (Note-Opening protection of glazing can be achieved with either impact-resistant glazing or with a protective covering over non-impact-resistant glazing): 1.

Sections R301.2.1.2 and R612.9 address the ability of glazing in exterior window and doors of buildings located in wind borne debris regions to resist shattering from flying debris during high wind events. a.

Section R612.9 states “Protection for exterior windows and glass doors in buildings located in wind-borne debris regions shall be in accordance with Section R301.2.1.2”. R301.2.1.2 is addressed in Section 5.0-A.1.c of this document.

b.

Section R612.9.1 “Entitled “Fenestration* Testing and Labeling”): In reference to wind-borne debris protection, this section states that “Fenestration shall be tested by an approved independent laboratory, listed by an approved entity, and bear a label identifying manufacturer, performance characteristics, and approved inspection agency to indicate compliance with the requirements of the following specification”: 

ASTM E 1886 and ASTM E 1996 (see Section 8.0 of this document for information on ASTM E 1886 and ASTM E 1996); or  AAMA 506 (2006 referenced standard) – Voluntary Specification for Hurricane Impact and Cyclic Testing of Fenestration Products. * Definition of FENESTRATION in Section R202 of the NCRC: Skylights, roof windows, vertical windows (whether fixed or moveable); opaque doors; glazed DOI File # WP-002-10 (Rev. 2013)

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doors; glass block; and combination opaque/glazed doors. c.

2.

Section R301.2.1.2: This Section requires the glazing in the openings in the exterior envelope of a building located in a wind-borne debris region to resist breakage by flying debris. The code allows glass in the opening to be impact-resistant glazing or non-impact-resistant that is protected by a covering. Both impact resistant glazing and coverings protecting non-impact resistant glazing shall meet the requirements of the Large Missile Test of ASTM E 1996 (2006 referenced standard) and ASTM E 1886 (2006 referenced standard).

Glazed openings in garage doors: Section R301.2.1.2 addresses protection of garage doors glazed openings in exterior walls of buildings located in a wind-borne debris region. This Section requires glazed protection to meet the requirements of an approved impact-resisting standard (by the CEO/AHJ) or ANSI/DASMA 115 (2005 referenced standard). Note that ANSI/DASMA 115 is the “Standard Method for Testing Garage Doors: Determination of Structural Performance under Missile Impact and Cyclic Wind Pressure”.

B. NCBC (Note-Opening protection can be achieved with either impact-resistant glazing or with a protective covering over non-impact-resistant glazing*): 1.

Section 1609.1.2 addresses the protection of glazing in exterior window and doors located in wind borne debris regions from flying debris. This Section states “glazing in buildings shall be impact resistant or protected with an impact-resistant covering meeting the requirements of an approved impact-resistant standard (by the CEO/AHJ) or ASTM E 1996 (2005 standard) and ASTM E 1886 referenced herein as follows” (see Section 8.0 of this document for information on ASTM E 1886 and ASTM E 1996): a.

“Glazed openings located within 30 feet of grade shall meet the requirements of the large missile test of ASTM E 1996.”

b.

“Glazed openings located more than 30 feet above grade shall meet the provisions of the small missile test of ASTM E 1996.” * Note: Attachments of the impact-resistant glazing to the window frame and the attachment of the window frame to the building structure as well as the attachment of impact-resistant coverings to protect non-impact-resistant glazing shall be designed to resist component and cladding wind pressures as determined in accordance with the provisions of Minimum Design Loads for Buildings and Other Structures in ASCE 7 (2005 reference standard). The intent is for the design pressure rating on the opening component label to equal or exceed the required design pressure calculated using ASCE-7.

2.

Exceptions in Section 1609.1.2 where glazed openings of buildings located in wind borne debris regions are not required to be protected: a.

Exception # 2 states “Glazing in Occupancy Category I buildings as defined in Section 1604.5, including greenhouses that are occupied for growing plants on a production or research basis, without public access shall be permitted to be unprotected”.

b.

Exception # 3 states “Glazing in Occupancy Category II, III or IV buildings (as defined in Section 1604.5) located over 60 feet above the ground and over 30 feet above aggregate surfaced (stone ballast or gravel) roofs located within 1,500 feet (horizontally) of the building shall be permitted to be unprotected.” However, note that conversely, glazing in Occupancy Category II, III or IV buildings located less

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than 30 feet above aggregate surfaced (stone ballast or gravel) roofs located within 1,500 feet (horizontally) of the building shall be protected. Protection of glazing for these openings shall meet the requirements of the Small Missile Test of ASTM E 1996. For additional information, also refer to Drawings 1, 2 & 4 in Attachment B of this document under “16.0-Illustations”. 3.

6.0

Glazed openings in garage doors: Section 1609.1.2.2 addresses protection of garage doors glazed openings in exterior walls of buildings located in a wind-borne debris region. This Section requires protection to meet the requirements of an approved impact-resisting standard (by the CEO/AHJ) or ANSI/DASMA 115 (2005 referenced standard) which is the “Standard Method for Testing Garage Doors: Determination of Structural Performance under Missile Impact and Cyclic Wind Pressure”.

Code Requirements for Wood Structural Panels Used as Wind Borne Debris Protection A. NCRC: “Exception” under R301.2.1.2 and accompanying Table R301.2.1.2 addresses prescriptive code requirements for wood structural panels. Refer to Drawings 1-6 in Attachment A of this document under “16.0-Illustations” that also includes information on wood structural panel requirements by the NCRC. B. NCBC: Exception #1 under 1609.1.2 addresses prescriptive code requirements for wood structural panels. Refer to Drawings 3 & 4 in Attachment B of this document under “16.0Illustations” that also includes information on wood structural panel requirements by the NCBC.

7.0

Code Design Requirements for Exterior Window, Door, and Garage Door Assemblies for Resisting Wind Pressure A. NCRC: 1.

Section R301.2.1 addresses wind load requirements in designing a lateral-force-resisting system for a building. This Section also states “Where loads for curtain walls, exterior windows, skylights, garage doors and exterior doors are not otherwise specified, the loads listed in Table R301.2(2) adjusted for height and exposure using Table R301.2(3) shall be used to determine design load performance requirements for curtain walls, exterior windows, skylights, garage doors and exterior doors”.

2.

Exterior Window and Door Assemblies a.

Section R612.5: This section addresses the performance of exterior windows and door assemblies in any wind zone. It reiterates Section R301.2.1 by restating that these openings “shall be designed to resist the design wind loads specified in Table R301.2.(2), adjusted for height and exposure per Table R301.2.(3)”*. Table R301.2(4) tabulates the required design pressures, adjusted for height, for fenestration located in 90 and 100 mph wind zones. Pressures in this table are for Exposure Category B. The design pressure rating on the window or door label must exceed the adjusted pressure from Table R301.2(3) or the pressure from Table R301.2(4). The design and anchorage requirements, when located in the building envelope (referenced as “main force-resisting system”), are addressed in Section R612.10. These sections of the code ensure the window or door and its anchorage have the structural integrity to sustain static pressures imparted by the wind and do not address impact-resistance. * Note: Chapter 45, entitled “High Wind Zone”, is a North Carolina addition to the

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IBC. Based on Table R301.2.(2), Table R4502(a) lists the required design pressures for windows and doors in wind zones from 110 mph to 130 mph and includes the adjustment for height and exposure per Table R301.2.(3)”. b.

3.

Section R612.6 addresses testing and labeling of exterior windows and sliding doors: 

This Section states that these opening elements shall be “tested by an approved independent laboratory, and bear a label identifying manufacturer, performance characteristics and approved inspection agency to indicate compliance with AAMA/WDMA/CSA 101/I.S.2/A440. Exterior side-hinged doors shall be tested and labeled as conforming to AAMA/WDMA/CSA 101/I.S.2/A440 or comply with Section R612.8”.



Section R612.8 is an exception to Section R612.6 for exterior windows and door assemblies not included within the scope of Section R612.6. An example is a custom window or door which is not a manufactured “off the shelf” item. Section R612.8 allows these windows and doors to be tested in accordance with ASTM E 330 (2002 referenced standard) as an alternate test standard which requires testing to 1.5 times the required design pressure. Note that glass in assemblies covered by this exception shall comply with Section R308.5 which states “site built windows shall comply with Section 2404 of the International Building Code”, i.e. the NCBC.

Overhead garage doors: a.

As addressed in Section R301.2.1, the loads listed in Table R301.2(2) that are adjusted for height and exposure using Table R301.2(3) or Table R301.2(4), shall be used to determine design load performance requirements for garage doors. (Note: Chapter 45, entitled “High Wind Zone”, is a North Carolina addition to the IBC. Based on Table R301.2.(2), Table R4502(b) lists the required design pressures for garage doors and includes the adjusted for height and exposure per Table R301.2.(3)”.)

Figure 7: Garage door blown inward from hurricane–force winds.

b.

Section R612.7 states “Vehicular access doors shall be tested in accordance with either ASTM E 330 or ANSI/DASMA 108, and shall meet the acceptance criteria of ANSI/DASMA 108”. Section R612.8 allows these garage doors to be tested in accordance with ASTM E 330 (2002 referenced standard) as an alternate test standard which requires testing to 1.5 times the required design pressure.

c.

Figure 7 is an example of a garage door blown inward from hurricane-force winds.

B. NCBC: 1.

Section 1405.13 states “Windows and doors installed in exterior walls shall conform to the testing and performance requirements of Section 1715.5”. Section 1405.13.1 requires windows and doors to be installed in accordance with approved manufacturer’s instructions, including fastener size and spacing and calculations based on maximum loads and spacing used in the tests.

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2.

Section 1715.5 permits two methods for testing wind loading for exterior window and door assemblies. The design pressure rating of these assemblies in buildings shall be determined in accordance with Section 1715.5.1 or with Section 1715.5.2 for any wind zone. a.

Section 1715.5.1 states, “Exterior windows and sliding doors shall be tested and labeled as conforming to AAMA/WDMA/CSA101/I.S.2/A440. The label shall state the name of the manufacturer, the approved labeling agency and the product designation as specified in AAMA/WDMA/CSA101/I.S.2/A440. Exterior sidehinged doors shall be tested and labeled as conforming to AAMA/WDMA/CSA101/I.S.2/A440 or comply with Section 1715.5.2. Products tested and labeled as conforming to AAMA/WDMA/CSA 101/I.S.2/A440 shall not be subject to the requirements of Sections 2403.2 and 2403.3.Exterior side-hinged doors shall be tested and labeled as conforming to AAMA/WDMA/CSA101/I.S.2/A440 or comply with Section 1715.5.2”.

b.

Section 1715.5.2, as an alternate to Section to 1715.5.1, states that Exterior windows and door assemblies (not provided for in Section 1715.5.1) “shall be tested in accordance with ASTM E 330. Exterior window and door assemblies containing glass shall comply with Section 2403. The design pressure for testing shall be calculated in accordance with Chapter 16. Each assembly shall be tested for 10 seconds at a load equal to 1.5 times the design pressure”.

3.

8.0

Structural performance (pressure testing) of garage doors shall be determined in accordance with either ASTM E 330 or ANSI/DASMA 108, and shall meet the acceptance criteria of ANSI/DASMA 108.

Basic Description of ASTM E 1886 and ASTM E 1996 A. ASTM E 1886 (Note: The 2005 edition is referenced in Chapter 35 of the NCBC and the 2006 edition is referenced in Chapter 44 of the NCRC) - Standard Test Method for Performance of Exterior Windows, Curtain Walls, Doors and Storm Shutters Impacted by Missile(s) and Exposed to Cyclic Pressure Differentials. 1.

ASTM E 1886 specifies the requirements for performing the missile tests. “Scope” under 1.1 of ASTM E 1886 states “This test method determines the performance of exterior windows, curtain walls, doors, and impact protective systems impacted by missile(s) and subsequently subjected to cyclic static pressure differentials”. The scope continues with “This test method is applicable to the design of entire fenestration or impact protection systems assemblies and their installation. The performance determined by this test method relates to the ability of elements of the building envelope to remain un-breached during a windstorm”.

2.

The NCBC requires compliance with the large and possibly the small missile test of ASTM E 1886, based on the height of the glazed opening above grade. For additional information in this document, refer to Drawings 1, 2 & 4 under “16.0 Illustrations Attached to this Document”. ASTM E 1886 specifies a small and a large missile used in the test as follows: a.

Section 6.2.7.1 in ASTM E 1886 describes the physical characteristics of the small missile used in the test as a solid steel ball. The ball must be within a specified tolerance range for mass (weight) and diameter. The test is conducted at an impact speed between 0.40 and 0.85 of the basic wind speed (3-second wind gust in accordance with ANSI/ASCE 7).

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b.

c.

Section 6.2.7.2 in ASTM E 1886 describes the physical characteristics of the large missile used in the test as a No. 2 or better Southern Yellow Pine or Douglas Fir 2 X 4 dimension lumber having an American Lumber Standard Committee accredited agency mark. The lumber must be within a specified tolerance range for mass (weight) and length with no defects (knots, splits, etc.) within 12” of the impact end. The test is conducted at an impact speed between 0.10 and 0.55 of the basic wind speed (3-second wind gust in accordance with ANSI/ASCE 7). Section 6.2.7.3 in ASTM E 1886 permits other types of missiles to be used in the test. This section states “Any other representative missile with mass, size, shape, and impact speed as a function of basic wind speed determined by engineering analysis”.

B. ASTM E 1996 (2006 referenced standard) - Standard Specification for Performance of Exterior Windows, Curtain Walls, Doors and Storm Shutters Impacted by Windborne Debris in Hurricanes

9.0

1.

This standard establishes a uniform set of specifications and performance guidelines required to conduct Test Method E 1886.

2.

The intent of this specification, as stated in Section 1.3 under scope, is to provide “a basis for judgment if the ability of the applicable elements of the building envelope to remain un-breached during a hurricane, thereby minimizing the damaging effects of hurricanes on the building interior and reducing the magnitude of internal pressurization”.

NCRC Code Requirements when Replacing Windows in Existing Residential Dwellings Located in a Wind-Borne Debris Region A. Repairing or replacing a non-protected window opening(s) in an existing dwelling located in a wind-borne debris region may trigger the requirement for the new window opening(s) in the existing openings to comply with current code for protection from flying debris. For information on this topic, refer to the NCDOI-OSFM Website at www.ncdoi.com/osfm :     

At the NC Department of Insurance, Office of State Fire Marshal Website, click on “Engineering and Codes” where a menu will “drop down”; On this menu click on “Code Enforcement Resources”, after which a new screen will appear; Click on “Code Interpretations” from the directory on the left hand side of this screen and a list of the types of states codes will appear on the right hand side of this screen; On the line entitled “Residential”, click on “2012” which is on the same line at the far right; This directs you to the “2012 Residential” site where you click on the document entitled “R301.2.1.2 – Windborne Debris Protection”. This document is dated December 18, 2012.

B. Where the NCDOI OSFM Website Document entitled “R301.2.1.2 – Windborne Debris Protection” (dated December 18, 2012) triggers the requirement for wind-borne debris protection, note that a building permit, issued by the AHJ, is required before this work can commence. 10.0

Submittals the Code Enforcement Official may request for Verification of Code Compliance or Equivalency At their discretion, the following is suggested information the code enforcement official/authority having jurisdiction may request to confirm code compliance: A. Submission may include a copy of the following:

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1.

Copy of ASTM E 1886: a. b.

2.

2005 referenced standard for compliance with the NCRC; or 2006 referenced standard for compliance with the NCBC.

Copy of ASTM E 1996 (2006 referenced standard), Large Missile Test and/or Small Missile Test, as appropriate for the NCRC or the NCBC.

B. Submission may include a copy of the Test Report from an independent third party testing laboratory certifying that the protective covering complies with ASTM E 1886 and ASTM E 1996: 1.

The laboratory shall be accredited (for the specific test method under consideration) by the International Accreditation Service, Inc. (IAS) or an accreditation service recognized by IAS. Website for link to list of IAS accredited test laboratories is http://www.iasonline.org/More/search.html.

2.

Copy of the test report, to include information listed under Item 12 of ASTM E 1886.

3.

Impact-resistant coverings shall be tested as an assembly. The assembly shall include the material, frame (if a part of the system), attachment hardware/anchors, & all associated components normally used for product installation as defined by the manufacturer or as required for a specific project.

4.

The test report for compliance with ASTM E 1886 shall include the basic wind speed under which the product was evaluated.

5.

For protective coverings such as flexible fabric/woven mesh screens that deflect on impact from wind-borne debris, the test report for compliance with ASTM E 1886 shall indicate minimum clear dimension required between the protective covering and the glazing.

C. For work being performed under the NCBC, the submission may include written confirmation from the applicant to the AHJ that there is, or is not, an aggregate surfaced roof within 1500 feet of the project, as addressed in Exception # 3 under Section 1609.1.2 of the NCBC. D. At the discretion of the CEO/AHJ, the submission may include a Shop Drawing from the product manufacturer that should contain the following information: 1.

Maximum width and height of single opening for which the covering assembly has been tested for compliance with ASTM E 1886 & ASTM E 1996 may be requested with the manufacturer’s requirements for the conditions of the project.

2.

Provide details of manufacturer’s anchorage requirements for the type of substrate (concrete, masonry, wood framing/studs, aluminum, etc.) on which the covering will be secured. Include description/specification of type of fasteners for each substrate material, maximum spacing of fasteners and minimum embedment/penetration depth of fasteners into each type of substructure.

3.

Each sheet of shop drawings shall be sealed by a design professional, registered in North Carolina.

4.

Exception under Section R301.2.1.2 of the NCRC addresses structural wood panels with the requirement that permanent attachment hardware is to be “corrosion-resistant”. a.

For protective coverings to properly function when needed, recommendation is that all permanent components, including attachments, anchors, fasteners, etc. are to be corrosion-resistant. (Note-“corrosion-resistant” is not defined in the codes. However,

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the American Iron and Steel Institute (AISI) states corrosion-resistant “is a material's ability to resist deterioration caused by exposure to an environment”. b.

Materials (usually metals) deteriorate at different rates. For example, a stainless steel alloy will resist corrosion for a longer time period than hot-dipped galvanized steel. Also note that plastic based materials can become brittle in a harsh coastal environment. It is important for a fastener or other part of an opening protective to be replaced when it corrodes or deteriorates to the degree that it can no longer serve the function for which it was intended.

E. If the covering protecting the non-impact-resistant glazing deflects inward towards the glazing upon impact, the minimum separation distance required between covering and glazing by the manufacturer should be provided. An example is a flexible fabric protective covering. F. Submission may include a copy of the manufacturer’s printed installation instructions. G. Submission may include written verification from contractor/installer that the substrate for attaching the protective covering is a solid and an acceptable substrate, capable of accommodating the attachments/fasteners to sustain the loads as required by Code. H. The Code Enforcement Official may require a sample of the proposed product/covering, including proposed anchorage, be included as a part of the submission for review and approval of the work. (After approval, the CEO can return the sample to the applicant for incorporation into the project.) 11.0

Maintaining Emergency Escape and Rescue Opening Code Requirements in Wind-borne Debris Regions In addition to providing natural lighting and ventilation, operable windows can also serve as a means for a building occupant to escape or to be rescued by emergency responders during a building fire or similar life-threating event. An exterior opening required by code to serve as an emergency escape and rescue opening can be located in a wind-borne debris region and also required by code to be protected from hurricane force winds. After a high wind event has passed and opening protection is no longer necessary, the opening protective shall be removed before the space is reoccupied if the protective covering prevents the ability of an opening to serve as a code required means of escape and rescue. A.

NCRC - Section R310 addresses emergency escape and rescue exterior opening requirements by the Residential Code. Section R310.1 describes the location where the opening requirements apply. 1.

Where Section R310.1 requires an exterior glazed opening to serve as a means of emergency escape and rescue and Section R301.2.1.2 requires the same opening to have protection from wind-borne debris, recommendation is for the submission to include: a.

From the Designer or Contractor where a protective covering(s) is to be left permanently in place at an exterior glazed opening(s), written confirmation that the protective covering also complies with Section R310.4. Section R310.4 requires an opening to be releasable or removable from the inside of the room without the use of a key, tool, special knowledge or force greater than that which is required for normal operation of the escape and rescue opening and this should also apply to the permanently installed protective covering. Further, the permanently installed protective covering, when in the opened position, shall not restrict or hinder the ability of the glazed opening to serve as an operable emergency escape and rescue opening, as required by Section R310.2; or

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b.

From the Building Owner where the protective covering is not to be left permanently in place at an exterior glazed opening(s), written confirmation that the protective covering shall be removed from the exterior glazed opening(s) after wind-borne debris protection is no longer required before the room is reoccupied (for compliance with Section R310). An example is wood structural panels screw attached from the exterior.

B. NCBC - Requirements for Emergency Escape and Rescue:

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1.

Section 1029 addresses emergency escape and rescue opening requirements. Section 1029.1 describes the occupancy groups, room types and other areas where the opening requirements apply, unless exempted by one of the Exceptions listed under Section 1029.1.

2.

Where Section 1029.1 requires an exterior glazed opening to serve as a means of emergency escape and rescue and Section 1609.1 requires the same opening(s) to have protection from wind-borne debris, recommendation is for the submission to include the following: a.

From the Designer or Contractor: Where a protective covering(s) is to be left permanently in place at an exterior glazed opening(s), written confirmation that the protective covering also complies with Section 1029.4. Section 1026.4 requires an opening cover to be releasable or removable from the inside (of the room) without the use of a key, tool, special knowledge or force greater than that which is required for normal operation of the escape and rescue opening. Further, the permanently installed protective covering shall not restrict or hinder the ability of the glazed opening to serve as an operable emergency escape and rescue opening, as required by Section 1029.1; or

b.

From the Building Owner: Where the protective covering is not to be left permanently in place at an exterior glazed opening(s), written confirmation that the protective covering shall be removed from the exterior glazed opening(s) after windborne debris protection is no longer required before the room is reoccupied (for compliance with Section 1029). An example is wood structural panels screw attached from the exterior.

Recommendations for Job Site Consideration by the Code Enforcement Official A. The Code Enforcement Official may require a copy of the manufacturer’s printed installation instructions and, if applicable, approved shop drawings to be kept at the job site during construction until certificate of occupancy for the project is issued by the CEO/AHJ. B. The Code Enforcement Official may require all protective coverings to be marked with a label, indicating the manufacturer’s name, product name and/or model number, size and compliance with ASTM E 1886 and/or ASTM E 1996 and applicable reference standard under which it was tested. Recommendation also is for the third party testing to be identified on the label. If any labels are temporarily affixed to the product, no label should be removed until the Code Enforcement Official approves the installation of the product. C. If the protective coverings are not designed to remain in place permanently at the opening, the Code Enforcement Official may require that one of each type of protective covering is be left in place over an opening at the time the Code Enforcement Official visits the site to inspect the installation. The Code Enforcement Official should have access to all stored protective coverings.

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Other Recommendations for Consideration by the Code Enforcement Official A. The Code Enforcement Official may require verification that the installer is certified by the manufacturer to install their product, if the manufacturer has such a program. B. For protective covering systems not permanently mounted and designed to be removed when not in use, the Code Enforcement Official may require that each covering be marked or labeled in some manner to identify which specific opening the cover is intended to protect on the structure. This can be of particular importance when the protective coverings are wood structural panels, as addressed in Section 6.0 of this document. C. The Code Enforcement Official may require written certification by the installer/contractor that coverings are installed in accordance with the manufacturer’s printed installation instructions and, if applicable, the approved shop drawings. D. If written confirmation is not submitted that there is no aggregate surface roof within 1500 feet of the proposed work, the Code Enforcement Official may require that all glazed opening protection be designed to comply with Exception # 3 under Section 1609.1.2 of the NC Building Code, as applicable for the conditions of the project.

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References 1. 2012 North Carolina Residential Code 2. 2012 North Carolina Building Code 3. 2009 International Residential Code and Commentary by the International Code Council, Inc. 4. 2009 International Building Code and Commentary by the International Code Council, Inc. 5. ASTM E 1886 - Standard Test Method for Performance of Exterior Windows, Curtain Walls, Doors and Storm Shutters Impacted by Missile(s) and Exposed to Cyclic Pressure Differentials (Note - 2005 edition referenced in Chapter 35 of the NCBC and the 2006 edition referenced in Chapter 44 of the NCRC.) 6. ASTM E 1996 (2006 referenced standard) - Standard Specification for Performance of Exterior Windows, Curtain Walls, Doors and Storm Shutters Impacted by Windborne Debris in Hurricanes 7. Hurricane Retrofit Guide by the State of Florida-Division of Emergency-Bureau of Mitigation

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Credits for Figures A. Figure 1: 2009 International Building Code Commentary, figure 1609.1.2 B. Reprinted from the Hurricane Retrofit Guide by State of Florida, Division of Emergency, Bureau of Mitigation: - Figure 2: Impact Resistant Glass after being struck by 2 x 4 Missile; - Figure 3: Example of Roll-Down Shutter; - Figure 4: Example of Side-Hinged Shutter; - Figure 5: Example of Horizontal Sliding Accordion Shutter System; - Figure 7: Garage Door blown inward. C. Figure 6: (http://www. hardwaresource.com) - Example of Bermuda/Bahamas Style Shutters

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Illustrations Attached to this Document  Attachment A - Drawings 1-6: Illustrations on Wind Borne Debris Protection - 2012 North Carolina Residential Code  Attachment B - Drawings 1-4: Illustrations on Wind Borne Debris Protection - 2012 North Carolina Building Code  Attachment C - Continental United States Land Falling Hurricanes 1950-1994

This Document does not constitute an evaluation of any vendor’s product nor does this document imply that the Code Enforcement Official must approve any specific material, design, or method.

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Attachment C- Continental United States Land Falling Hurricanes 1950-1994

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