International Codes Updates Wanda Edwards, PE RCI, Inc. 1500 Sunday Dr., Ste. 204, Raleigh, NC 27607 Phone: 919-859-0742 • E-mail: wedwards@rci-online.org RC 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 ow • Ma rc h 1 4 – 1 9 , 2 0 1 9 E dwa r d s • 5 3 Abstract This presentation will focus on changes to the 2018 International Codes, and upcoming proposals to the 2021 International Codes. The presentation will cover the International Building Code, the International Existing Building Code, and the International Energy Conservation Code. Topics will include changes to reroofing, polypropylene siding, roof coverings, underlayment, building-integrated photovoltaics, air barriers, and secondary drainage requirements, along with the reasons for the code changes. Code proposals submitted by RCI and RCI’s position on certain code proposals will be discussed. Speaker Wanda Edwards, PE – RCI, Inc. – Raleigh, NC WANDA EDWARDS is the senior director of technical services for RCI. Before joining RCI, Edwards served as director of code development for the Institute for Business and Home Safety (IBHS). Previously, Edwards served as deputy commissioner and chief engineer for the Engineering Division of the North Carolina Department of Insurance, whose responsibilities included administration and regulation of the building codes. She was a Fulbright scholar to Trinidad and Tobago and previously owned a design/construction/development firm. Edwards earned her bachelor’s degrees in civil engineering and architecture from North Carolina State University. She is a licensed professional engineer and serves on various committees within ASTM, ICC, and NIBS. 54 • Edwards RCI International Convention and Trade Show • MarcRCh 14-19, 2019 The International Codes publish a new edition of the family of codes every three years. During the time between editions, proposals are submitted and hearings are held to amend the codes. The first hearings are heard by committees of stakeholders and professionals. The committees each have areas of responsibility. For instance, the International Building Code (IBC) is divided into four areas: fire safety, egress, general, and structural. There are committees for each area, which meet in the spring. The committees make an initial determination about proposals, and then there is a public comment period followed by final action hearings in the fall. The 2018 International Codes have been out for almost a year (Figure 1); jurisdictions are reviewing, amending, and adopting the codes. Meanwhile, work has begun to create the 2021 International Codes. This presentation will discuss the major changes to the 2018 IBC, 2018 International Energy Conservation Code (IECC), and the 2018 International Existing Building Code (IEBC). Italicized words are language contained within the International Codes. CHANGES TO THE IBC The provisions of this code shall apply to the construction, alteration, relocation, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures. The exception to the scope of the IBC is one- and two-family dwellings not exceeding three stories above grade plane. CHAPTER 2 DEFINITIONS Building-Integrated Photovoltaic Roof Panel (BIPV Roof Panel) A photovoltaic panel that functions as a component of the building envelope. As the definition states, BIPV roof panels function as a component of the building envelope and are therefore subject to code requirements for roof coverings. These panels are larger than BIPV shingles. The panels are a thin-film layer and are either rectangular or a rounded shape. In addition to the new definition, a new section has been added to Chapter 15, Section 1507.18, which details the proper application of the panels. Continuous Insulation Insulating material that is continuous across all structural members without thermal bridges, other than fasteners and service openings. It is installed on the interior or exterior, or is integral to any opaque surface of the building envelope. The term “continuous insulation” was introduced into the code in 2015; however, it was not defined. The code refers to insulated sheathing, which is a rigid board product. Insulated sheathing materials meet the criteria for continuous insulation, but not all continuous insulation products meet the criteria for insulated sheathing. Table 1405.3.2, Class III Vapor Retarders, has been revised to use the term “continuous insulation” instead of “insulated sheathing.” Roof Coating A fluid-applied, adhered coating used for roof maintenance or roof repair, or as a component of a roof covering system or roof assembly. See Figure 2. This definition was added to acknowledge products used within the industry. International Codes Updates RCI International Convention and Trade Show • MarcRCh 14-19, 2019 E Edwards • 55 Figure 1 – International Building Code. Courtesy of ICC. Figure 2 – Roof coatings. Courtesy of Roof Coatings Manufacturers Association. Section 1511.3.1, Roof Recover, was revised to specify the acceptable substrates for coatings. A compatible change was also included in the IEBC. CHAPTER 14 EXTERIOR WALLS Section 1404 Installation of Wall Coverings Table 1404.2 Weather Covering Minimum Thickness (was Table 1405.2) The minimum required thickness of masonry and stone veneer weather coverings has been updated to align with current industry standards. Two types of masonry are covered in the table—anchored masonry and adhered masonry. Anchored masonry is attached with ties or anchors. Adhered masonry veneer is applied to masonry using mortar or other approved adhesives. Terms such as “stone (cast artificial)” have been changed to “architectural cast stone.” 1404.18 Polypropylene Siding The 2015 IBC allowed polypropylene siding only on exterior walls of buildings of Type VB construction. Type VB buildings have the most lax fire resistance requirements of all building types. Types I through IV construction were allowed to have combustible materials on the exterior if they passed NFPA 268 testing, and met surface area, height, and radiant heat limits as specified in the code. The 2018 IBC allows polypropylene siding on buildings of Types I through V construction if they meet the requirements of Section 1403.12, which requires that the siding be certified and labeled as conforming to ASTM D7254 and other requirements of the code, such as height limitations and maximum wind speed. If the siding installed exceeds the limits specified in the code, calculations showing the adequacy of the siding must be submitted with the construction drawings. CHAPTER 15 ROOF ASSEMBLIES AND ROOFTOP STRUCTURES Section 1504 Performance Requirements Section 1504.3 Wind Resistance of Nonballasted Roofs This section was modified to remind users that the wind loads on the roof coverings shall be determined using the allowable stress design method. The introduction of ASCE 7-10 and the use of ultimate wind speeds have caused confusion with design professionals when calculating wind loads on roof coverings. 1504.3.3 Metal Roof Shingles A new section has been added to the code to address metal roof shingles (Figure 3), which were previously covered under metal roof panels. This section was added to because metal shingles are not the same as asphalt shingles or other roof systems in some respects. The applicable wind testing standards are ASTM D3161, FM 4474, UL 580, or UL 1897. ASTM D3161 is a fan-induced test that was developed for asphalt shingles. The 2015 version of D3161 has been revised to evaluate wind resistance of the product’s rigidity without the contribution of the sealant or adhesive and would, therefore, be applicable to metal shingles. Section 1505 Fire Classification Section 1505.9 Rooftop-Mounted Photovoltaic Panel Systems Previously, this section was titled “Photovoltaic Panels and Modules.” The section title was changed to “Rooftop-Mounted Photovoltaic Panel Systems,” and a new standard was added, UL 2703, entitled Mounting Systems, Mounting Devices, Clamping/Retention Devices, and Ground Lugs for Use with Flat-Plate Photovoltaic Modules and Panels. The reason for the change was because the slope of the photovoltaic (PV) system is important in determining the fire classification. The position of the PV panel is established by the racking system. The new standard UL 2703 allows for testing of multiple panels for each racking system. Either standard may be used to determine the fire classification. Section 1505.10 Roof Gardens and Landscaped Roofs A reference was added to clarify that roof gardens and landscaped roofs must comply with Section 1505.1 and 1507.16, as well as ANSI/SPRI VF-1. This change was made to avoid confusion that roof gardens and landscaped roofs may be exempt from these sections of the IBC. Section 1507 Requirements for Roof Coverings Section 1507.1 Underlayment Underlayment and ice barrier requirements have been relocated from various sections of the codes into one new section. Previously, underlayment requirements were specified by roofing covering material. Now all the underlayment requirements are in one section. Self-adhered membranes are now permissible as an alternative to underlayment provisions for high winds. The threshold for enhanced requirements has been changed from vasd = 120 mph to vult = 140 mph to be consistent with the International Residential Code (IRC). Figure 3 – Metal shingles. Courtesy of Schroer & Sons. 56 • Edwards RCI International Convention and Trade Show • MarcRCh 14-19, 2019 Section 1507.1.1 Exception #1 As an alternative to the underlayment requirements of 1507.1, this exception has been revised to include the requirement that self-adhered membranes comply with ASTM D1970 and be installed in accordance with the manufacturer’s installation instructions. Self-adhered membranes are not required, but are an alternative to the underlayment provisions for high-wind areas. Section 1507.1.1 Exception #2 As an alternative, this section allows the use of a minimum 4-in.-wide strip of self-adhering membrane applied to the joints of the roof decking with one layer of underlayment on top. The underlayment may be rated for design speeds less than 120 mph. Section 1507.1.1 Exception #3 As an alternative, two layers of underlayment may be permitted. As a result of testing conducted by the Institute for Business and Home Safety (IBHS), this method provides equivalent protection to a self-adhered membrane. The requirements for this alternative are very detailed and very specific in the exception. Section 1507.8 Wood Shingles Section 1507.8.9 Label Required Each bundle of wood shingles shall be identified by a label showing the approved grading or inspection agency. Labels will aid code officials in determining code compliance. Section 1507.9 Wood Shakes Section 1507.9.10 Label Required Like wood shingles, each bundle of shakes shall be identified by a label showing the approved grading or inspection agency. The labels will help code officials determine code compliance. Section 1511 Reroofing Section 1511.3 Roof Replacement This section has been revised to allow the application of a roof coating over some roofs as listed in the section. Allowable substrates include an existing roof coating, metal roof panel or shingle, mineral-surfaced roll material, built-up roof, modified-bitumen roofing, thermoset and thermoplastic single ply and spray polyurethane foam roofing system. The roof coating may be applied without removing the existing roof covering. Section 1507.18 BIPV Roof Panels The BIPV Panel section is new and has been added to the roof coverings in the code. (See Figure 4.) The new section covers the deck, underlayment, high-wind attachment, ice barrier, and attachment requirements. The panels must be installed on a solid, close-fitting deck, and on roof slopes of 2:12 or greater. The underlayment shall comply with ASTM D226, ASTM D4869, or ASTM D6757, applied in shingle fashion, parallel to and starting from the eave, lapped 2 inches and fastened. CHAPTER 16 STRUCTURAL DESIGN Section 1603 Construction Drawings Section 1603.1 General This section was revised to coordinate the 2018 IBC with ASCE 7-16, Minimum Design Loads and Associated Criteria for Buildings and Other Structures. The change requires that construction drawFigure 4 – BIPV panels. Courtesy of Solar Power World. RCI International Convention and Trade Show • MarcRCh 14-19, 2019 E Edwards • 57 ings for conventional light-frame construction must show rain load data, along with other loads, on the drawings. Section 1603.1.3 Roof Snow Load Data This section was changed to require that drawings must indicate the slope factor(s), Cs with the roof snow load data (Figure 5). Section 1603.1.9 Roof Rain Load Data Rain intensity and rain load data shall be shown on the drawings, regardless of whether rain loads govern the design. Having this information on the drawings will assist designers and owners when making alterations to the roof. Section 1609 Wind Loads Changes to ASCE 7-16 have been discussed in previous white papers. At the 2017 convention, a presentation was given on the changes to ASCE 7-16. Please refer to the convention proceedings for details on the changes. CHAPTER 23 WOOD Section 2303 Minimum Standards and Quality Section 2303.2.2 Other Means During Manufacture The section is revised to clarify that it refers to wood products impregnated with chemicals. Further, it states that the use of paints, coatings, stains, or other surface treatments are not approved methods of protection as required in this section. In the 2015 IBC, lumber was either pressure impregnated or impregnated by other means during manufacture. Fire-retardant-treated wood is typically solid-sawn lumber or plywood that is pressure treated. For engineered lumber, “other means during manufacture” refers to a process where veneers, chips, or adhesives are treated with fire-retardant chemicals. Surface treatments such as paints, coatings, or stains are considered an alternate method or design and are addressed in Section 104.11, and will have an evaluation report that must demonstrate equivalency with the code. Acceptance criteria include durability, degradation from rain exposure, flaking or peeling due to shrinkage and expansion, and effects on stiffness and strength of the wood substrate. Section 2304 General Construction Requirements Table 2304.9.3.2 Mechanically Laminated Decking Since the introduction of power-driven nails, their equivalency to conventional nails has been questioned. The 2015 IBC expanded the fastener table in Chapter 23 and attempted to provide equivalent power-driven nail sizes to conventional nail sizes. However, there were still questions about whether a specific manufacturer’s power-driven nail was equivalent to conventional 20d nails, as the information was proprietary. A new alternative fastener schedule for construction of mechanically laminated decking has been added to the 2018 IBC, giving equivalent power-driven fasteners for 20-penny nails, which have a smaller diameter than 20d nails. Because the nails are smaller, they are spaced closer together. See Figure 6. Table 2304.10.1 Ring-Shank Nails The 2015 IRC addressed ring-shank nails for roof sheathing, but the IBC did not. Tests have shown ring-shank nails (Figure 7) to be at least equivalent to and better than smooth-shank nails. The 2018 IBC and IRC are now aligned by requiring 8-penny common or ring-shank nails when nailing 6 inches and 12 inches on center for roof sheathing. The spacing for ring-shank nails is less than for 8d box nails. Section 2304.10.5 Fasteners in Treated Wood Staples in preservative-treated wood and fire-retardant-treated wood are now required to be made of stainless steel. The Figure 5 – Snow on sloped roof. Courtesy of ICC. 58 • Edwards RCI International Convention and Trade Show • MarcRCh 14-19, 2019 code has added staples for use in some wood-to-wood connections. The staples must be stainless steel in areas subject to corrosion. Section 2304.11 Heavy Timber Construction The heavy timber provisions of Chapter 23 have been reorganized, and the 2015 IBC table on engineered lumber dimensional equivalencies—previously located in Section 602.4—has been moved into Section 2304.11. Previously, the provisions for heavy timbers were located throughout the code. Now the requirements have been consolidated to one location. The code has been revised to allow cross-laminated timber (CLT) to be used for two-hour exterior walls in Type IV construction (heavy timber construction). Section 2304.12.2.5 Supporting Members for Permeable Floors and Roofs Structural members supporting moisture-permeable floors or roofs that are exposed to the weather shall be of naturally durable or preservative-treated wood unless separated from the floor by an impervious moisture barrier. The impervious moisture barrier must allow for drainage of water that penetrates the moisture-permeable floor topping to prevent deterioration of the structural members due to trapped moisture. This change will promote the removal of water and moisture to prevent floors from being saturated and rotting, molding, and decaying. When a roof leaks, occupants typically see there is a roof leak, but it is not always visible when water penetrates a balcony. Section 2304.12.2.6 Ventilation Beneath Balcony and Elevated Walking Surfaces Enclosed balconies and elevated walkways that are exposed to rain, snow, and drainage from irrigation shall be provided with openings that provide a cross ventilation area not less than 1/150 net area for each separate space. The provision clarifies that when a balcony or elevated walking surface serves as a weather-resistant barrier and the joist spaces below are enclosed, cross ventilation is required similar to enclosed rafter spaces in roofs. The 2018 IBC brings in ventilation requirements similar to those found in Chapter 12 and is specific to enclosed balconies. CHAPTER 25 GYPSUM BOARD, GYPSUM PANEL PRODUCTS, AND PLASTER Section 2510 Lathing and Furring for Cement Plaster (Stucco) Section 2510.6 Water-Resistive Barriers A new exception was added to this section to prevent the accumulation of moisture behind the stucco in humid climates. In many climates, a vapor-permeable water-resistive barrier can be too vapor permeable, and moisture can be driven inward. Moisture being driven into the wall can cause water damage and molding. With stucco walls, the stucco can absorb moisture during rain, and Figure 6 – Mechanically laminated decking. Courtesy of Western Wood Structures, Inc. Figure 7 – Ring-shank nails. Courtesy of ICC. RCI International Convention and Trade Show • MarcRCh 14-19, 2019 E Edwards • 59 when the sun comes out and heats the wall, the moisture can be driven into the wall. In humid climates, the moisture can remain in the wall. Climate Zones 1A and 3A have the largest mold issues. An air space is now required between the stucco and the water-resistive barrier to allow transport of water out of the wall. Where a water-resistive barrier is installed over wood-based sheathing in Climate Zone 1A, 2A, and 3A, you must provide a ventilated air space between the stucco and the water-resistive barrier. In humid climates, moisture can remain behind the stucco. CHAPTER 26 PLASTIC Section 2603 Foam Plastic Insulation Section 2603.13 Cladding Attachment Over Foam Sheathing to Wood Framing This new section provides the requirement for cladding attachment over foam sheathing on wood framing. These provisions are consistent with requirements in the IRC. These fastening requirements were based on work performed by the New York Energy Research and Development Agency (NYERDA). The goal of the project was to ensure adequate performance of cladding over rigid foam sheathing. The project tested various cladding attachments over steel framing with various thicknesses of foam sheathing. The results were the basis of the code change. CHANGES TO THE IECC The IECC applies to commercial buildings and the buildings’ sites and associated systems and equipment. The code is now divided into two sections: one for the residential provisions, and one for the commercial provisions. Residential buildings shall meet the residential provisions of the IECC and commercial buildings shall meet the commercial provisions of the IECC. For buildings with mixed residential and commercial occupancies, each section of the building shall meet the applicable provisions. The residential portions of the building meet the residential provisions of the IECC, and the commercial portions of the building meet the commercial provisions of the IECC. (See Figure 8.) CHAPTER 2 COMMERCIAL PROVISIONS DEFINITIONS Air Barrier The definition of “continuous air barrier” was deleted from the code, being redundant with the definition of “air barrier,” which is also included in the code. The definition of “air barrier” was revised to clarify that an air barrier can be a single material or a combination of materials. The definition has been revised as follows: One or more materials joined together in a continuous manner to restrict or prevent the passage of air through the building thermal envelope and its assemblies. Approved The definition of “approved” was revised to be consistent with the other volumes of the codes. The definition previously said, “acceptable to the code official or the authority having jurisdiction.” It now says, “acceptable to the code official.” Building Thermal Envelope The basement walls, exterior walls, floors, ceilings, roofs, and any other building element assemblies that enclose conditioned space or provide a boundary between conditioned space and exempt or unconditioned space. This definition has been revised to include all the elements of the envelope. Cavity Insulation Insulation material located between framing members. This new definition aids in distinguishing cavity insulation from continuous insulation. Continuous Air Barrier Definition has Been Deleted With the modification to the air barrier definition, continuous air barrier is redundant. Fenestration Products classified either as skylights or vertical fenestration. Skylights are defined as being installed at a slope less than 60 degrees, and vertical fenestrations are installed at not less than 60 degrees. Entrance doors are now defined as a vertical fenestration product. Labeled Equipment, materials, or products to which have been affixed a label, seal, symbol, or other identifying mark of a nationally recognized testing laboratory, approved agency, or other organization concerned with product evaluation that maintains periodic inspection of the production of the labeled items and whose labeling indicates either that the equipment, material, or product meets identified standards or has been tested and found suitable for a specified purpose. Products that are required to be labeled must be tested by a nationally recognized testing laboratory, approved agency, or an organization that provides product evaluation. The definition of “approved” has been changed. An approved agency is one that is acceptable to the code official, allowing the code official to accept the agency providing the label. SECTION C301 CLIMATE ZONES The climate map that is included in the 2018 IECC is the same map that was included in the 2015 IECC. However, the climate map in ASHRAE 90.1, Energy Standard for Buildings Except Low-Rise Residential Buildings, is a different map from the one in the IECC. If your path to compliance is ASHRAE 90.1, use the map in that standard. If your path to compliance is the IECC, use the map in the IECC. (See Figure 9.) C303.1 BUILDING THERMAL ENVELOPE INSULATION The exception to this section has been revised to clarify how above-deck insulation is identified. Labeling each piece of insulation is not practical, as the insulation is quickly covered up during construction. The exception requires that the packaging be labeled with the applicable R-value in accordance with the IBC Table 1508.2, “Material Standards for Roof Insulation.” C402.2.2 ROOF ASSEMBLY This section has been revised to require that above-deck insulation consist of two layers and Figure 8 – IECC. Courtesy of ICC. 60 • Edwards RCI International Convention and Trade Show • MarcRCh 14-19, 2019 shall be installed with staggered joints. An exception was added that two layers of insulation are not required when tapering to a roof drain. Two layers of insulation with staggered joints help to prevent the movement of air through the roof assembly. C402.5.1.1 AIR BARRIER CONSTRUCTION When penetrations of the air barrier occur, the code requires that the penetration be sealed. The code has been revised to require that the sealant allow for expansion and contraction of dissimilar materials and mechanical vibration. IEBC The IEBC (Figure 10) applies to the repair, alteration, change of occupancy, addition to, and relocation of existing buildings. The IEBC does not apply to detached one- and two-family dwellings and townhomes. CHAPTER 2 SECTION 202 DEFINITIONS Building Any structure utilized or intended for supporting or sheltering any occupancy. Existing Structure A structure erected prior to the date of adoption of the appropriate code, or one for which a legal building permit has been issued. There is also a definition of “existing building.” The code refers to existing buildings and existing structures and did not include a definition of “existing structure.” The terms are interchangeable, and this code change confirms that they are the same. Roof Coating A fluid-applied adhered coating used for roof maintenance, roof repair, or as a component of a roof covering system or roof assembly. This change was included in the IBC, and a discussion of the change is found above in the IBC portion of this paper. Substantial Structural Damage Substantial structural damage occurs when any of three conditions exist. The 2015 IBC listed two conditions. A new condition has been added to cover structural components that carry snow loads that support more than 30 percent of the roof area, whose capacity has been reduced by more than 20 percent from its pre-damage capacity and the remaining capacity is less than 75 percent of that required for new buildings. This change introduces a trigger for snow retrofit. There has been an increase in roof failures due to snow—particularly in the Northeast. Since a roof assembly may not represent more than 30 percent of the total building area, the trigger would not apply. The addition of the third condition makes it clear that snow loads can trigger a substantial structural damage condition. CHAPTER 7 ALTERATION LEVEL 1 Section 705 Reroofing Section 705.1 General The IEBC states when re-covering or replacing an existing roof covering, the work must comply with Chapter 15 of the IBC. An exception has been added to this section that was added to the 2015 IBC. The exception states when re-covering or replacing an existing roof covering, a secondary drainage system is not required to be installed if positive drainage is provided, and if one did not exist prior to the work. The IBC defines “positive drainage” as the drainage condition in which consideration has been made for all loading deflections of the roof deck, and additional slope has been provided to ensure drainage of the roof within 48 hours of precipitation. The ICC offers a number of reference books to help users. These publications include Significant Changes to the IBC, IBC Code Commentary, IECC Code Commentary, Building Code and Energy Code Essentials, and Complete Revision History to the 2018 I-Codes, which can be purchased at ICC’s website (www.iccsafe.org). These reference books, along with the 2018 IBC, IECC, and IEBC, were used in developing this paper. Figure 10 – IEBC. Courtesy of ICC. Figure 9 – ASHRAE climate zones map. Courtesy of ICC. RCI International Convention and Trade Show • MarcRCh 14-19, 2019 E Edwards • 61
