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HomeMy WebLinkAboutIEBC Code and Commentary ICC 2018100722987 AND T R FEMA.gov is being updated to comply with President Trump's Executive Orders. Thank you for your patience and understanding. I!; An officia l webs ite of th e Un ited States government Here 's how you know FEMA App ly for As sista nce Reports & Data Historic Structure Any structure that is: 1. Listed individually in the National Register of Historic Places or preliminarily determ i ned as meeting the requirements for individual listing on the National Register; 2. Certified or preliminarily determined as contributing to the historical significance of a registered historic district ; 3. Indivi dually listed on a state inventory of historic places; or 4. Individually listed on a local inventory of historic places . Communities may exempt historic buildings from NFIP substantial improvement and substantial damage requirements in either of two ways. First , they can exempt them through their definition of substantial improvement. Second , they can issue variances for historic structures . However, the improvement must not preclude the structures continued designation as a histor ic structure and must be the minimum necessary to preserve its historic character. National Flood Insurance Program Requirements ■ 59 .1 -Definition ■ 60 .6 -Va riances and exceptions o (a ) -Variances for Historic Structures Last updated J uly 8, 20 20 Return to t op_ 2. The vertical elements of the lateral force-resisting sys­ tem have suffered damage such that the lateral load­ carrying capacity of any story in any horizontal direc­ tion has been reduced by more than 10 percent from its predamage condition. • ❖ This defines earthquake damage where , even under small loads, the damage is significant. The proposed capacity loss thresh hold of 10 percent might appear small, but in Seismic Design Category D, E and F, with spectral acceleration less than 0 .4g, any decent building should have zero structural damage. This is important in the requirements for repair of earthquake damage in Chapters 5 and 6 of this code . EQUIPMENT OR FIXTURE. Any plumbing, heating , electrical, ventilating , air conditioning, refrigerating, and fire protection equipment , and elevators, dumbwaiters, escalators, boilers , pressure vessels and other mechanical facilities or installations that are related to building service s. Equipment or fixture shall not include manufacturing, production , or pro­ cess equipment, but shall include connection s from building service to process equipment. ❖ This definition outlines the type of building systems and devices that are considered to be categorized as equipment or fixtures . It is important to note that while the list is quite extensive, the definition does not spe­ cifically exclude the terms "manufacturing," "produc­ tion" or "process equipment." [A] EXISTING BUILDING. A building erected prior to the date of adoption of the appropriate code, or one for which a legal building permit has been issued. ❖ This term is used to identify those structures or build ­ ings that were constructed before the current edition of the code was adopted by the jurisdiction . Often erected under the provisions of an earlier edition of the code, the buildings are exempt from compliance with current code provisions unless otherwise stated, where a hazardous condition is present or where alterations or changes in building height and areas are made. [A] 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. ❖ In the IBC and IEBC the term "existing structure" is used interchangeably with "existing building ." Both basically mean the same thing in the context of these codes ; therefore , both have the same definition . [A] FACILITY. All or any portion of buildings, structures, site improvements , elements and pedestrian or vehicu lar route s located on a site . ❖ This term is intentionally broad and includes all por ­ tions within a site and all aspects of that site contain ­ ing features required to be accessible. This include s parking areas ; exterior walkways leading to accessi- DEFINITIONS ble features ; recreational facilities, such as play­ grounds and picnic areas ; and any structures on the site (see also the commentary to the definition of . "Site" in the IBC). [BS] FLOOD HAZARD AREA. The greater of the follow­ ing two areas : 1. The area within a flood plain subject to a I-percent or greater chance of flooding in any year . 2 . The area de signated as a flood hazard area on a com­ munity's flood hazard map , or otherwise legally desig- nated. • ❖ The Federal Emergency Management Agency (FEMA) prepares Flood Insurance Rate Maps (FIRMs) that delineate the land area subject to inun­ dation by the 1-percent annual chance flood . Some states and local jurisdictions develop and adopt maps of flood hazard areas that are more extensive than the areas shown on FEMA's maps . For the purpose of the code, the flood hazard area in which the requirements are to be applied is the greater of the two delineated areas. [A] HISTORIC BUILDING. Any building or structure that i s one or more of the following: 1. Listed, or certified as eligible for listing, by the State Historic Preservation Officer or the Keeper of the National Register of Historic Places , in the National Register of Historic Places . 2. Designated as historic under an applicable state or local law . 3. Certified as a contributing resource within a National Register, state designated or locally designated historic district. ❖ This definition specifies the criteria for consideration as a historic building . Chapter 11 contains the provi­ sions for buildings that qualify as historic buildings. [B] NONCOMBUSTIBLE MATERIAL. A material that, under the conditions anticipated , will not ignite or burn when subjected to fire or heat. Materials that pas s ASTM E136 are considered noncombustible materials . ❖ A material that will not ignite or burn when subjected to fire or heat or that successfully passes the ASTM E136 test is considered to be noncombustible. The test deter­ mines whether a building material will act to aid com­ bustion or add appreciable heat to a fire . A material may have a limited amount of combustible content but not contribute appreciably to a fire; thus , it may still qualify as noncombustible . PRIMARY FUNCTION. A primary fun ction is a major activity for which the facility is intended . Areas that contain a primary fun ction include , but are not limited to, th e customer services lobby of a bank, the dining area of a cafeteria , the meeting rooms in a conference center, as well as offices and 2018 IEBC"'CODE and COMMENTARY 2-3 100722987 11 ~111!]~1-lWl[IJ~l•"·~•JI] :(~l}IJ ~ [~ 11 Copyright C 201s ICC. ALL RIGHTS RESERVED. Accessed by Erik Cortinas (erikc@cohirhopt".com), (City of Fairhope) OrderNumber•100122sis1 on Jun 21, 201si 06:40 AM (PDT) pursuant to License ... ~---~!~!.IJ! __ -~!J.k!_~ ...... _!! _ .. ~ ... !! . _ Agrttment with ICC. No further reproduction or distribution authorized. Single usu only, copying and networking prohibited. ANY UNAlITHORlZED REPRODUCTION OR DISTRIBUTION JS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LI CENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER. PRESCRIPTIVE COMPLIANCE METHOD gency veh icle garages are needed to be in service during and immediately after a major windstorm or earthquake event. Where th \s applies, the structure m_ust be analyzed for seismic load s and shown to be adequate under the provisions of the IBC for new buildings . The impact this may have on the existing structure and the minimum design loads depends on the risk cate ­ gory for the new (proposed) occupancy category compared to those required for the current occu­ pancy category . Other less apparent impacts will result due to the fact that the basic design loads prior to considering the risk category (for example , wind pressure) required by the IBC will often be different than the predecessor model code used in the build ­ ing 's original design . Exception 1 is based on a similar exception to Chapter 16 of the IBC and recognizes the difficulty of making an older structure comply with the seismic requirements for a new structure . It provides general guidance to the code official and designer on areas that need to be investigated when compliance with the seismic requi rements for new buildings is difficult. Exception 2 contains requirements and exceptions that apply to buildings housing two or more occupan ­ cies that are classified in different risk categories . The general requirement for a change of occupancy resulting in a mixed-use building is that the entire structure must be designed in accordance with the requirements of the most critical risk (higher hazard classification) category because it resists the· earth ­ quake forces as a unit. This is consistent with Chap ­ ter 16 of the IBC. The actual exception to this rule is where a new occupancy having a risk category com ­ prises no more than 10 percent of the total building area and it is not considered an essential facility. Exception 3 refers to Chapter A 1 of Appendix A. GSREB , which is applicable to URM wall buildings. These build ings would likely fall into the category of buildings already exempt under Exception 2. Never­ theless, thi s exception provides a direct 'link to the GSREB requirements for URM buildings that undergo a change of occupancy . Section A 102 .2 limitations make Appendix Chapter A 1 applicable to Risk Cate ­ gorie s I and II in Table 1604 .5 of the IBC . 506 .4 .4 Access to Risk Category IV. Any stru ctu re th at pro ­ vi des operational access to an adj acent stru cture ass ign ed to R isk Category IV as th e res ult of a change of occup ancy shall i tself satisfy the req uirement s of Sec tion s 1608, 160 9 and 1613 of th e Inten;iatio nal Building Code . For co mplian ce wi th Section 1613, I nternat ional Bu ilding Code -level sei smi c forces shall b e used . Where ope rati onal access t o th e R isk Category IV struc tu re is less than 10 feet (3 048 rmn ) fr om ei ther an interior lot line or fro m an oth er stru ctu re, access protection from po t ential fallin g d ebri s shall be prov id ed . ❖ Thi s section is· intended to ensure access for the occupant to es se ntial facilitie s after an earthquake by proh ibiting a cce ss through an adjacent structure that doe s not comply with the se ismic criteria for essential 5-16 INTERNATIONAL CODE COUNCI~ facilities . These requirements are the result o f les ­ sons learned from previous earthquakes in which essential facilities have been rendered out of service be.cause of the failure of an adjacent. structure or a structure's exterior components . These requirements are based on ASCE 7 as well as FEMA 368 . SECTION 507 HISTORIC BUILDINGS 507 .1 Historic buildings. The provisions of thi s cod e that require improvements relative to a building 's exis ting co ndi­ ti on or, in the case of rep a irs, that require impro vements rela­ ti ve to a building 's pre damage condition, shall not be mandatory for historic b uilding s unless specific ally req uired by thi s section. ❖ This section provides an exception • from code requirements when the building in question has his­ toric value . The most important criterion for the appli ­ cation of this section is that the building must be essentially accredited as being of historic significance by a qualified party or agency (see the definition of "Historic building" in Section 202). Usually, this is done by a state or local authority after careful review of the historical value of the building . Most, if not all , states have such authorities, as do many local juris­ dictions . The agencies with such authority can be located at the state or local government level or through the local chapter of the American Institute of Architects (AIAJ. This section also clarifies that the code generally does not apply unless specifically required by this section . There are two subsections . The first deals with addressing distinct hazards to life . The second deals with flood hazard areas and neces­ sary upgrades as applicable . Note, as will be dis ­ cussed, most historic buildings need not comply with the flood hazard requirements . 507.2 Life safety hazards . The provisi ons of thi s co d e shall appl y to his toric buildings judged by th e building offi cial to constitute a di stin ct life saf;ety hazard . ❖ This section provides the authority to address distinct hazards to life safety . This can address issues such as structural instability or blocked or severely limited exits . Once a distinct hazard is established , the provi ­ sions of the code will apply. The extent of application is at the discretion of the code official. [BS] 507 .3 Flood hazard areas. Within fl oo d haza rd are as es tabli shed in accordan ce with Section 1612 .3 of th e I nterna­ tio n al Bu ildin g Code, or Sec ti on R3 22 o f th e In te rna tio na l _Resid ential Code, as appli cabl e, where the work propo se d co nstitutes sub stan tial improvement, th e building shall be brou ght into co mplian ce with Sec tion 161 2 of th e In terna­ ti onal Bu ilding Co d e, or Sec tio n R 322 of th e International Residen tia l Cod e, as applicable. Exception: Hi sto ri c b uildings meeti ng an y of th e fo ll ow ­ ing criteria nee d not be bro ught int o complian ce: 1. Li sted or preliminarily d etermin e d to be eli gible for lis ting in th e N ational R egister of Hi stori c Pl aces. 2 . Determined by the Secretary of the U .S. Department of Interior as contributing to the historical signifi­ cance of a registered historic district or a district pre­ liminarily determined to qualify as an historic district. 3. Designated as historic under a state or local historic preservation program that is approved by the Department of Interior . ❖ With respect to provisions applicable to buildings in flood hazard areas, the discretion given in Section 507 .1 allowing the code official to waive the require­ ments for historic structures extends only to historic structures that meet the specific limitations in the exception to this section. For example, location in a historic district does not qualify a structure as historic . Care must be taken to ensure that work on such his­ toric structures will not cause them to lose their con­ tinued listing or designation. If improvements or repairs cause a structure to lose its listing or designa­ tion as a historic building , then the code official must enforce the substantial improvement requirements. Owners of historic structures should consider mea­ sures to reduce flood damage to the extent practical. For additional guidance, see FJ:MA P-467-2, Flood­ plain Management Bulletin on Historic Structures, and FEMA P-758 . [BS] 507 .4 Structural. Historic buildings shall comply with the applicable structural provisions in this chapter. Exceptions: 1. The code official shall be authorized to accept exist­ ing .floors and existing live loads and to approve operational controls that limit the live load on any floor. 2 . Repair of substantial structural damag e is n ot required to comply with Section s 405 .2.3, and 405.2.4. Substantial structural damag e shall be repaired in accordance with Section 405 .2 .1. ❖ Any proposed work on historic buildings must comply with the structural provisions that apply based on the nature of that work . In other words, the classification of any proposed work is the first consideration . Exception 1 authorizes the code official to accept existing floors and approve operational controls that limit the live load on any such floor . This could be achieved by posting load limit signs in conspicuous locations . Actual loads on floors are typically less than the code-required loads. This section permits consideration of the actual loads as opposed to the probabilistic loads used for new design . Section 1201 .2 allows alternative approaches through the evaluation and report . Exception 2 addresses the argument that historic buildings should not be subject to expensive and dis ­ ruptive wind and seismic retrofits when those retrofits are required by repairs . Alterations, additions, reloca­ tions , and changes of occupancy are all voluntary; those projects should be subject to sensible upgrade requirements , even for historic buildings , and the proj- PRESCRIPTIVE COMPLIANCE METHOD ects can be scoped and budgeted to accommodate these requirements with due regard for historic pres­ ervation. Repairs, however, are not voluntary, so an upgrade required by repair might be at odds with the priorities of preservation . Not everyone will agree with this approach; after all, historic buildings are expected to provide adequate safety , too. But if historic bu il d­ ings should ever be exempt from the code 's sensible wind and seismic retrofit requirements , it should be in the case of involuntary repairs. 2018 IEBC"'CODE and COMMENTARY 5-17 i"Offirfe INTERNATIONAL CODE COUNCI[ Y±0 §ID. -wiO'e.~0110::u.01 i OGEO.ffil¼-»J,2§LlljJY;®i' /;0~W'l~0 >M' -ta!i'-~i"Q~·,,..rilM!o~ ~-toa,1":t' @' i /o0'9.1Bil)OO.rui +"«®«c-r.t6'Ai'-» 11•~;, ,1-©~ >Wo0t 0<©,>®il'~ :fl!¾.~ c<;~»X>l~•·»«-ia.'"§:Mc"'-'' tW ,~" •a,-¾-,,xr..o:;:ECnEi l2ff ¥1:Di(jjri(Eyj >IION O>lii~i >lb~ 11 ~mi woo 0.XO:Xil10'iw;f w 11Yi 1100; 0.Xm.ao11cr uoca mOOIEl:(D)ii ; N'i'>E>Coo:i'if ,o,moo::mo ,a illlJCEoXi o Chapter 6: Classification of Work General Comments This chapter provides an overview of the process for the repair, alteration and restoration of existing buildings . A brief description is provided that identifies the differ­ ences between the three levels of alterations . In addi ­ tion, the topics of additions , historic buildings and relocated buildings are mentioned . SECTION 601 GENERAL 601.1 Scope. The provisions of this chapter shall be used in conjunction with Chapters 7 through 12 and shall apply to the alteration, addition and change of occupancy of existing structures, including historic and moved structures, as refer~ enced in Section 301.3.2. The work performed on an existing building shall be classified in accordance with this chapter. ❖ This section establishes when the regulations con ­ tained in the code must be followed, whether all or in • part. Something must happen (modification to · an existing building or allowing an existing building or structure to become unsafe} for the code to be appli­ cable . The code is not a maintenance document requiring periodic inspections that will, in turn, result in an enforcement action. Periodic inspections are addressed by the International Fire Code® (IFC ®). 601.1.1 Compliance with other alternatives. Alterations, additions and changes of occupancy to existing structures shall comply with the provisions of Chapters 7 through 12 or with one of the alternatives provided in Section 301.3. ❖ This section offers the code user compliance options. In addition to being able to use the provisions listed in Chapters 7 through 12, there are three other compli­ ance alternatives listed under Section 301 .3. First, Section 301 .3 .1 offers a prescriptive compli­ ance method for repairs , alterations , additions and changes of occupancy as long as they comply with Chapter 3 of the code and the IFC. Second , Section 301.3 .2 describes the work area compliance method that requires compliance with the appli'cable provi­ sions of Chapters 7 through 12. Third , Section 301.3.3 describes the performance compliance method that requires compliance with Chapter 14 . 601.2 Work area. The work area, as defined in Chapter 2, shall be identified on the constructi on documents . ❖ As defined in Chapter 2, a "Work area" is the area of all reconfigured spaces where work is occurring Purpose This chapter enables the contractor , design professional or code official to easily identify the classification of and the associated chapter in the code for building alter­ ations, additions and repairs . within the scope of a project. These areas are to be shown clearly on the construction documents . Work areas exclude other portions of the building where incidental work is ongoing . SECTION 602 ALTERATION-LEVEL 1 602.1 Scope. Level 1 alterations include the removal and replacement or the covering of existing materials , elements, equipment, or fixtures using new materials, elements, equip­ ment, or fixtures that serve the same purpose . ❖ Level 1 alterations represent the most basic or fore­ most level of building alterations . This includes the removal and replacement or the covering of existing materials, elements, equipment or fixtures . An exam­ ple would be the addition of a new roof to an existing building . Another example would be the removal of aluminum siding to be replaced with vinyl siding. 602.2 Application. Level 1 alterations shall comply with the provisions of Chapter 7 . ❖ Chapter 7 describes , in detail , the requirements for Level 1 alterations . It is important to note that historic buildings must also comply with this chapter unless there is a modification noted in Chapter 12 . Note that Level 1 alterations do not involve the reconfiguration of space . SECTION 603 ALTERATION-LEVEL 2 603.1 Scope. Level 2 alt erations include the reconfiguration of space, the ad dition or elimination of any door or window, the reconfiguration or extension of any system, or the instal­ lation of any additional equipment. ❖ Chapter 8 describes, in detail, the requirements for Level 2 alterations. The exception to Section 801 .1 allows bu ildings undergoing alterations that are 2018 IEBC"'CODE and COMMENTARY 6-1 INTERNATIONAL CODE COUNClt' Y±"§© . .vi O'e.~or..OOi ,uzj I iOG ~Ufil~>//4§UijJYc!®' c0l!il,Ulli"t ~·»w <t'W·~i"Q~•,,.~~ ~'ffii.9-'e±' Gl' iioO'Y.Ofiil)OOIW +"<@<t "Tj:O'#-» 11•~1 >f:@~ ~oClt'<®,>!l!if~ ~~ 0,:~»¼>i"•»«-tt'§:M''-'' l'!/4'>1©ti!j}" •~ ·¾-,,xna;:EmEl ru¥1:DiC£iNJE'ii wrii O>iii>l=Ei w~ 11 ~>N'.ill wrv10Juwf10iiE;i w 11Yi 11rul 0J6<i'C.ci011ucroca a100IE~ l NY>£>01ru'if>0,mCnrnO>(J l0JCEruu o CLASSIFICATION OF WORK exclusively the result of compliance with the accessi­ bility requirements of Section 705.2 to comply with Chapter 7. 603 .2 Application . Level 2 alte rati on s shall comply with the provisions of Chapter 7 for Level 1 {l,lterati ons as well as the provisions of Chapter 8. ❖ In addition to the provisions listed in Chapter 8, Level 2 alterations are also required to meet all of the provi ­ sions of Chapter 7, Level 1 alteraUons . This require ­ ment effectively compounds the requirements for someone planning to alter an existing structure. For example , if, during the process of replacing the alumi­ num siding on a building with vinyl siding , the building owner decides to eliminate one of four windows from a room , then this project would be classified as a Level 2 alteration and would, therefore , be 'required to meet the provisions of Chapters 7 and 8. SECTION 604 ALTERATION-LEVEL 3 604.1 Scope. Level 3 alteration s apply where the work area exceeds 50 percent of the building area. ❖ Any time the work area , as defined in Section 202 , exceeds one -half of the aggregate building area, it is considered to be a Level 3 alteration and, therefore , has to meet the requirements of Chapter 9 . In the code, a work area encompasses all portions of the existing building that are proposed to be reconfig -. ured . 604.2 Application. Level 3 alte rati ons shall comply with the provi si on s of Chapters 7 and 8 for Le vel 1 and 2 alterati on s, respectively, as well as the provision s of Chapter 9. ❖ Any project that qualifies as a Level 3 alteration proj­ ect must meet all of the requirements of Chapters 7, 8 and 9. SECTION 605 CHANGE OF OCCUPANCY 605 .1 Scope. Ch ange of occupancy provi si on s appl y where the activi ty is classified as a change of occupan cy as defined in Chapter 2. ❖ A change of occupancy in an existing structure may change the level of inherent hazards that the code was initially intended to address . This is done so that the applicable code require ­ ments adequately address the specific •hazards of the new occupancy . For example , a change from an existing mercantile occupancy to a business occu­ pancy renders all Group B provisions applicable to all portions of the structure where the occupancy has changed . 6-2 605.2 Application . Changes of occupancy shall comply with the provisions of Chapter 10. ❖ This section indicates compliance with Chapter 10 for changes of occupancy. Chapter 10 contains provi­ sions frequently used for existing structures since the occupancy in a building or structure often changes during the life of the building. SECTION 606 ADDITIONS 606 .1 Scope. Provisions for additions shall apply where work is classified as an addition as defined in Chapter 2 . ❖ Any project that would increase the floor area, the number of stories in a building or the height of a structure would qualify as an addition . 606.2 Application. Additions to existin g buildings shall com­ ply with the provisions of Chapter 11 . ❖ Additions to existing structures are specifically cov - ered in Chapter 11 of the code . • SECTION 607 HISTORIC BUILDINGS 607 .1 Scope. Histori c building provisions shall apply to buildings classified as historic as defined in Chapter 2. ❖ The most important criterion for the application of this section is that the building must be certified as being of historic significance by a qualified party or agency. Usually this is done by a state or local authority after careful review of the historical value of the building . Most, if not all , states have such authorities, as do many local jurisdictions. The agencies with such authority can be located at the state or local govern ­ ment level or through the local chapter of the Ameri­ can Institute of Architects (AIA). Other considerations for classification as a historical building include the structural condition of the building (in other words , whether it is structurally sound), its proposed use , its impact on life safety and how the intent of the code, if not the letter, will be achieved. 607.2 Application. Except as specifi cally provided for in Chapter 12, hi stori c buildin gs shall comply with applicable provisi ons of this code for the type of work being performed . ❖ Chapter 12 covers the various aspects of existi ng his ­ toric structures and includes specific sections on repairs , fire safety , alterations , change of occupancy and structure . In the absence of any specific require­ ments or provisions in Chapter 12 , the remainder of the code is applicable to work proposed for historic buildings . 2018 IEBC"'CODE and COMMENTARY INTERNATIONAL CODE COUNCI[ Y±0 §Bl. -wi o·e>lM611(fi w I 1 OG!ceiml¼--»J,2§UiµY:!®' c~l¥l~•,,w ..W·~:L"Q~•,,,.fi®m<' ~Mfic;eH' G' i ro o·9.1mt,OO aD\ +0 ,«1,:«t ~Cl'Ai'-» 11'<1i>, ,,~~ >lM60t 0<<8?,®11'<1iY.»±' :!!!¾~ o<;~»X>I "'»«->&" '§:1¼0 "" tW >>©l!!j)'' 0 C!i. •¾-,,X!>Q;EmEi QN ~1C£iNJEYi >!ION O>liT ~i >00>111 !:m i w~i a,([00 r..(J'iw;i w 11'1 11ru i ~ 011u Ol'Jw mOO IE~ i NY>l':,mai~ >6>CnCa'.'.rno ,(J i a1 (EOJ(j o SECTION 608 RELOCATED BUILDINGS 608.1 Scope. Relocated building pro visions shall apply to relocated or moved buildings . ❖ Any structure that is relocated or moved to a different lot or a new location on the same lot falls within the scope of Section 608 . Structures that are relocated or moved are required to comply with the provisions applicable for new con­ struction. The moved structure may comply with the alternative provisions of Chapter 14 instead of the code requirements for new structures, which may be particularly useful if the moved structure is older than the effective date of the adoption of the building codes in the jurisdiction . The fire separation distance of the moved structure must also comply with the requirements for new structures even if the compli­ ance alternative provisions in Chapter 14 are used to meet the code requirements . 608 .2 Application. Relocated buildings shall comply with the provisions of Chapter 14 . ❖ The requirements for relocated or moved buildings are found in Chapter 14 of the code. CLASSIFICATION OF WORK 2018 IEBC"'CODE and COMMENTARY 6-3 INTERNATIONAL CODE COUNCI~ Y±0 ~. -wiO'e~or..O'.':i >UZi Ii 00 f=Wl'1½»---»)%iliiJY:!®' i;0~W't~·,M' -<W·"§:l!'Q~-~~ ~Olai1B3±' Gl' ie:'i6'9.laiM6ru +0 «®<t ~<'.'1N -» r,•0,1 ,1-©~ ><i'Yoat"<®,>l!!!il'~ ~~ c<;~»X>i ,,.»«->02 '§:M""-'' t¼'»©ll!j)" 0 8.. •¾.,,~EmEi Qlif ¥EDi w N£ii wl\i O>ili ,i:el w~ r, rcm1 wooi ruuoo~ w r,'i'i r,rui 0.XMDOr,u uoCc':i mOOIE~ 1 Nv>£{na)YT ,o,moomo ,o i wCEO)Q o Chapter 12: Historic Buildings General Comments This section prov ides some overall exceptions from code requirements when the building in question has historic value. The most important criterion for the application of this section is that the building must be essentially accredited as being of historic significance by a qualified third party or agency. Usually, this is done by a state or local authority after careful review of the historical value of the building . Most, if not all, states have such authori­ ties, as do many local jurisdictions . The agencies with such authority can be located at the state or local gov ­ ernment level or through the local chapter of the Ameri­ can Institute of Architects (AIA). Other considerations include the structural condition of the building (in other words, whether the building is structurally sound), its proposed use , its impact on life safety and how the intent, if not the letter, of the code will be achieved . SECTION 1201 GENERAL 1201.1 Scope. This chapter is intended to provide means for the preservation of historic buildings . Historic buildings shall comply with the provisions of this chapter relating to th eir repair, alteration, relocation and change of occupancy. ❖ This section establishes that this chapter deals with the requirements for the repair, alteration, relocation and change of occupancy of buildings previously defined by the code as historic . Note that the code would not regard a reconstruction of a historic build ­ ing as qualifying for treatment under this chapter , even if the building is reconstructed entirely from orig ­ inal, stored materials and assemblies . [BS] 1201 .2 Report. A historic building undergoing alter­ ation or change of occupancy shall be investigated and evalu ­ ated. If it is intended that the building meet the requirem ents of this chapter, a written report shall be prepared and filed with the code officia l by a registered design professional where such a report is necessary in the opinion of the code officia l. Such report shalJ be in accordance with Chapter 1 and shall identify each required safety feature th at is in com­ pliance with this chapter and where com plian ce with other chapters of these provi sion s woul d be damaging to the con­ tributing historic features . For buildings assigned to Seismic Design Category D, E or F , a struct ural evaluation describing , at a minimum , the vertical and horizontal elements of the lat­ eral force-resisting system and any strength s or weaknesses 2018 IEBC ®CODE and COMMENTARY Purpose A large number of existing buildings and structures do not comply with current building code requirements for new construction . Although many of these buildings are potentially salvageable, rehabilitation is often cost pro ­ hibitive because they may not be able to comply with all of the requirements for new construction. At the same time , it is necessary to regulate construction in existing buildings that undergo additions, alterations, renova­ tions, extensive repairs or change of occupancy. Such activity represents an opportunity to ensure that new construction complies with current building codes and that existing conditions are maintained , at a minimum, to their current level of compliance or are improved as required . To accomplish this objective and to make the rehabilitation process easier, this chapter allows for a controlled departure from full compliance with the tech­ nical codes without compromising the minimum stan­ dards for fire prevention and life safety features of the rehabilitated building . therein shall be prepared . Additionally, the report shall describe each feature that is not in compliance with these pro­ visions and shall demonstrate how the intent of these provi­ sions is co mpli ed with in providing an equivalent level of safety. ❖ This section provides for a report that acts as a tech­ nical backup for the code official's judgment. The intent is to be able to retain a record of the decisions and the basis for those decisions for future reference . The definition of "Historic building" refers to listing/ eligibility for national register , state designation, inclu­ sion in a survey or contributing to a national or state historic district. Contributing features may be limited to those features in nominations , historic structure reports or other such documents . This represents a systematized approach for evaluating proposals of equivalent performance (see the definition of "Historic building " in Section 202). 1201.3 Special occupancy exceptions-museums. Where a building in Group R-3 is used for Group A, B or M purposes such as museum tours , ex hi bits, and other public assembly activities, or for museums less than 3,000 square feet (279 m2), the code official may determine th at the occupancy is Group B where life safety conditions can be demonstrated in accordance with Section 1201.2 . Adequate means of egress in such buildings , which may include a means of maintaining doors in an open position to permit egress, a limit on building occupancy to an occ upant load permitted by the means of 12-1 100722 987 INTERNATIONAL CODE COUNCI[ Copyright C 2018 JCC. ALL RJGHTS RESERVED. Accessed by Erik Cortinas (erlkc@cofairhope.com), {Qty of Fairhope} Order Number •100722987 on Jun 27, 2019 06:•o AM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRJBUTION JS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIM INAL PENAL Tl.ES THEREUNDER HISTORIC BUILDINGS egress cap aci ty, a limit on occ upancy of certain areas or fl oors , or supervision by a p erson kn owledg eable in the emer­ gency exiti ng proce dures, shall be prov ided . ❖ This s ection acknowledges that dwellings used as mu seum s and other public assembly activities are a special case . The provision allows a small museum or historic hous e in a mus e um use to demonstrate life safety using operational controls that would not be permitted in most other uses. This is likely to be effective becaus e of the high degre e of supervision that would be necessary for security reasons in this occupancy . In this case , the building occupancy is classified as Group B even though it may contain assembly or mercantil e us e s . It would also permit the occasional use of a re sidential building for tours and museum us e . [BS] 1201 .4 Flood hazard areas. In fl ood haza rd areas, if all proposed wo rk, includin g rep airs, work required because of a change of occupancy, and alterati ons, con stitutes substantial improvement, then th e existing building shall comply with Secti on 1612 of th e In te rn ational Buildin g Co de, or Sec ti on R322 of th e Internatio nal Resid ential Code, as appli cable . Exception : If a historic b uild ing will continu e to b e a histo ric buildin g after the pro p osed work i s compl e ted , th en the pro posed work is not considered a substantial improvement. For the purposes of thi s exc eption , a historic building is any of the fo llowing: 1. Li sted or prelim inari ly determin ed to be eli gibl e for li sti ng in the Nati onal Register of Hi stori c Places . 2. Determined b y th e Secretary of th e U .S . Dep artment of Interior to contribute to the hi stori cal signifi cance of a registered hi storic dis tri ct or a di stri ct prelimi ­ narily determined to qu alify as a hi storic di strict. 3. D esignated as his tori c und er a state or local hi stori c pre servati on progr am th at i s approved by the Department of Interi or. ❖ In flood ar eas , hi storic buildings that meet one of th e exception s are not required to comply with the flood provision s, including th e substantial improvement provision , as long as the building continues to be des ­ ignated as historic . However , if plans to sub stantially improve a hi storic building would result in th e loss of its histori c de signation , th e building would be required to be brought into compliance with th e requirem e nts for flood hazard areas . Th e cod e official may require applicants to con sult with the appropriate historic pres ervation authority to determine whether the pro­ po se d work will j eopardiz e a structure 's histori c des­ ignation . To th e exte nt practicable , owners of hi storic building s may wi s h to incorporate flood -re s istant pro ­ vi sion s wh e n such building s undergo re pair s and alt erations . If th e work on a hi storic structure doe s not cau se th e lo ss of its hi storic building e ligibility as a res ult of th e propo se d work, then th e work would not be consid e re d as a s ub stantial improvement ; th e re- 12-2 fore , the building would not have to comply with Sec ­ tion 1612 of the International Building Code® (I BC ®) or Section R322 of the International Residential Cqde® (IRC ®), as applicable . 1201.5 Un safe conditions . Condition s determined by the code official to be un safe shall be remedi ed . Work sh all not be required beyond what is required to remedy the unsafe co nditi on s. ❖ This section require s th e repair of identified unsafe condition s in historic buildings without triggering sec ­ ondary requirements . It is important to note the term "unsafe" in this section as it is specifically defined in Section 202 . It is a more general term than the term "dang erous," which is specific to structural conditions . SECTION 1202 REPAIRS 1202.1 General. Rep airs to any porti on of a historic building or stru cture shall be permitted with ori ginal or like m ateri al s and original methods of constru ction , subject to th e provi­ sions of thi s chapter. Haz ard ous mat erial s, such as as bestos and lead-b ased paint, shall not be used where the cod e for new constru ction wo uld not permit their use in build ings of simil ar occ upan cy, purpose and locati on . ❖ Re pairs with like materials may be needed for aes ­ thetic reasons or to meet material conservation needs . It is important to note that original or like mate­ rials can be used, but these materials cannot contain substances such as asbestos that are hazardous and would not be permitted under the current building code for new construction . 1202.2 Replacement. Repl acement of existin g or mi ssing fea tures using ori gin al material s shall be permitted . Partial replacement fo r rep ai rs th at match the original in co nfig ura­ tion , heig ht, and si ze shall be permitted . Replacement glazing in hazardous location s shall co mply with th e safety glazing requirements of Ch apter 24 of the In tern ati onal Build ing Code. Exception : Gl ass bl ock walls, louvered wind ows, and j al­ o usie s rep aired wi th like materials . ❖ In some ca ses, historic materials hav e not been tested for fir e resistanc e or structural performanc e but have b een s hown to pe rform adequately wh en in use . An excell ent example would be a railing , wh ere spacing , height or end condition s would not me et modern requirement s . If sections of a railing are mis sing or if re pairs are ne eded , the railing is not required to mee t th e code provi s ion s for new con ­ struction ; how ever , th e second paragra ph of thi s sec ­ tion re quires upgrading to th e sa fety gl a zing requir e ment s of Chapte r 24 of th e IBC , sinc e th e re is an establi shed ha zard and th e co st to fabri cate a hi s­ toric ally corr ect re production of a prop er materi a l is ne gligibl e . 2018 IEBC ®CODE and COMMENTARY 100722987 HHll:UMUIHMIIIl)l]ll{IUJ:{ijll Copyright C 2018 ICC. ALL RIGHTS RESERVED. Accessed by Erik Cortinas (erikc@cofairhope.com), (City of Fairhope) Order Number •10072298' on Jun 27, 2019 06:40 AM (PDT) pursuant to License Agreement with ICC. No further reproduction o r distribution authorized. Single user only, copying and networking prohibited. ANY UNAlITHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRJGHT ACT AND THE LICENSE AGR.E.EMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER. SECTION 1203 FIRE SAFETY 1203.1 Scope. Historic buildings undergoing alterations, changes of occupancy, or that are moved shall comply with Section 1203 . ❖ This section recognizes the unique aspects associ­ ated with older historical structures . It reinforces the importance of the means of egress pathway while granting the code official some latitud e in accepting some degree of variance in the egress components. (for example, direction of exit door swing, egress path width and height). 1203.2 General. Every historic building that does not con­ form to the construction requirements specified in this code for the occupancy or use and that constitutes a distinct fire hazard as defined herein shall be provided with an approved automatic fire-extinguishing system as determined appropri­ ate by the code official. However, an automatic fire-extin­ guishing sy stem shall not be used to substitute for, or act as an alternative to, the required number of exits from any facil­ ity. ❖ Fire -extinguishing systems are effective substitutes for some requirements that are typical for new con­ struction, particularly passive systems such as rated doors and corridors . By slowing or suppressing the development of a fire, a sprinkler system will make passive fire resistance unnecessary. This section also establishes that an automatic sprinkler system is not considered appropriate as a substi tution for a reduction in the required number of exits . 1203.3 Means of egress. Existing door openings and corridor and stairway widths les s than those specified elsewhere in thi s code may be approved, provided that, in the opinion of the code official , there i s sufficient width and height for a per­ son to pass through the opening or traverse the means of egre ss . Where approved by the code official , the front or main exit doors need not swing in the direction of the path of exit travel , provided that other approved means of egre ss hav­ ing suffici ent capacity to serve the total occupant load are provided . ❖ This provision would permit the continuance of a structure no more hazardous than before rehabilita ­ tion, with minimum standards of usability . Provisions for new construction would require that exit doors swing in the direction of exit travel for an occupant load exceeding 50 . 1203.4 Transoms. In full y sprinklered buildings of Group R-1 , R-2 or R-3 occupancy , existing transoms in corridors and other fire-re sistanc e-rated wall s may be maintained if fixed in the closed position . A sprinkler shall be in stalled on each side of the transom . ❖ This permits the retention of nonwired/nonrated glass in historic transoms in rated walls in residential occu­ pancies where protected by an automatic fire sprin­ kler system throughout the building. This section requires the transoms to be closed and specific pro ­ tection on both sides of the transoms . This approach HISTORIC BUILDINGS basically affords a level of safety equivalent to the passive protection provided by a rated corridor or other rated construction . 1203.5 Interior finishes. The existing interior finishes shall be accepted where it is demon strated that they are the historic finishes. ❖ While existing wood paneling or other finishes may not meet flame spread requirements for walls or ceil­ ings, this section allows the finishes to remain in place if they can be shown to be historic in nature. If not, there should be no reason not to address the flame spread rating of the materials since the sensi­ tivity of the historic nature of the building is no longer an issue. 1203.6 Stairway enclosure. In building s of three stories or less , exit enclosure construction shall limit the spread of smoke by the use of tight-fitting doors and solid elements. Such elements are not required to have a fire-resistance rat­ ing. ❖ Enclosure of stairways to control smoke would pro­ vide an improvement, but permitting the enclosure to be nonrated would allow for use of traditional materi­ als. Example enclosures include plain or wired glass, smoke-activated doors and similar assemblies . This provides for flexibility, but requires at least a minimum level of passive smoke control to protect stairways for exiting . 1203.7 One-hour fire-resistant assemblies. Where I -hour fire-re sistance-rated construction is required by these provi­ sions, it need not be provided , regardless of construction or occupancy , where the existing wall and ceiling finish is wood or metal lath and plaster. ❖ The substitution of standard , old-fashioned lath and plaster for 1-hour"-rated wall construction is a well­ established alternative and is considered as meeting the intent of the code to provide a safe path for exit. 1203.8 Glazing in fire-resistance-rated systems. Historic glazing materials are permitted in interior wall s required to have a 1-hour fire-resistance rating where the opening is pro­ vided with approved smoke seal s and the area affected is pro­ vided with an automatic sprinkler sys tem . ❖ Glazing of interior partitions can be vulnerable because of potential leakage around the edge of the glazing or because of heat -induced glass breakage. This provision addresses both concerns. The sprin­ kler system should be provided on both sides of the wall containing the glazing . 1203.9 Stairway railings. Grand stairway s shall b e accepted without complying with the handrail and guard requirements . Exi sting handrail s and guards at all stairw ays shall b e permit­ ted to remain , provided they are not structurall y dan ge rou s. ❖ New construction requirements for handrail and guardrail height have increased over the years . Since an ornamental railing is typically difficult to modify, however , particularly without significant architectural change, the code permits historic railings that are 2018 IEBC ®CODE and COMMENTARY 12-3 100722987 11 1111•,1]~1.1•1111~••"•1l1]J].~l}IJ, (~ 11 Copyright C201a ICC. ALL RIG HTS RESERVED. Accessed by Erik C~rtinas {erikc@cofa.irhope.com), {City of Fairhope) Order Number •100722987 on Jun 27, 2019 06:◄ 0 AM (PDT) pursuant to License •-~----!~!lJ! __ -~!J}!_~ . _!!_~ _ . ~ .!! . _ Agreement with ICC. No furt her rep roduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHOR1ZED REPRODUCTION OR DISTRIBUTION IS A .VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LI CENSE AGREEMENT, AND SUBJECT TO CIVIL AND CR1M1NAL PEN ALTIES THEREUNDER HISTORIC BUILDINGS essentially safe t_o remain . This also would allow handrail profiles that may not meet current grip requirements, provided that they are not structurally dangerous. 1203.10 Guards. Guards shall comply with Sections 1203 .10.1 and 1203 .10.2. ❖ This section establishes that guards in existing his ­ toric structures can remain in the configuration in which they were originally constructed. Guards would still have to conform to the restrictions in effect at the time the building was built. 1203.10.1 Height. Existing g uards shall comply with the requirements of Section 404 . ❖ Section 404 requires that repairs maintain the exist- ing level of protection. 1203.10.2 Guard openings. The spacing between existing intermediate railings or openings in existing ornamental pat­ terns shal l be accepted . Missing elements or members of a guard may be replaced in a manner that will preserve the hi s­ toric appearance of the building or structure. ❖ Requirements for voids in railings and grilles have become more stringent over the years . The spacing of a balustrade or ornamental pattern of a grille is fre ­ qu en tly a significant contributor to the building's his­ toric character . This provision enables the retention and repair of the se elements. 1203 .11 Exit signs. Where exit sign or egress path marking location would damage the historic character of the building, alternative exit signs are permitted with approval of the code official. Alternative signs shall identify the exi ts and egress path . ❖ Signs and exit path identification are still required', but location is permitted to be flexible within the limits of functionality . 1203.12 Automatic fire-extinguishing systems. Every his­ toric building that cannot be made to conform to the con­ struction requirements specified in the International Building Code for the occupancy or use and that constitut es a distinct fire hazard shall be deemed to be in compliance if provided with an approved automatic fire-exti ngui shin g system . Exception: Where the code official approves an alterna­ tive life-safety system . ❖ This term is the generic name for all types of auto­ matic fire-extinguishing systems, including the most common typ e: th e automatic sprinkler system . See Section 904 of the IBC for requirements for particular alternative a utomatic fir e -extinguishing systems, such as wet-chemical , dry -c hemical , foam , carbon dioxide , halon and clean agent systems. Note th at the alternative is specific to the construc­ tion requirements (in other word s, height and area limitations, construction typ e and pa ss ive fire resis ­ tance). Section 1203.2 sta tes that an automatic fir e­ extinguishing system is not a substitute for the reduc ­ tion in the number of exits from a facility . 12-4 The exception would allow the utilization of an alternative life safety system; however, it would have to first be approved by the code offi cia l or the local authority having jurisdiction. SECTION 1204 CHANGE OF OCCUPANCY 1204.1 General. Historic buildings undergoing a change of occupancy shall comply with th e applicable provisions of Chapter 10, except as specifically permitted in this chapter. Where Chapter 10 requires compli ance with specific require­ ments of Chapter 7, Chapter 8 or Chapter 9 and where those requirements are subj ect to the exceptions in Section 1202, the same exce pti ons shall apply to this section. ❖ Occupancy choice ideally minimizes code conflicts and the necessity for change . According to the Secre­ tary of the Interior's Standards for Treatment of His ­ toric Properties, "A property will be used as it was historically, or be given a new use that maximizes the retention of distinctive materials , features , spaces and spatial relationships ." Economic pressures, how­ ever, may dictate that a structure be used in a differ­ ent occupancy than that for which it was intended. 1204.2 Building area. The allowable floor area for historic buildings undergoing a change of occupancy shall be permit­ ted to exceed by 20 percent th e allowable areas specified in Chapter 5 of the International Building Code . ❖ This section permits an allowable floor area in excess of 20 percent as required by the IBC . This is critical, s ince changing the type of construction to be able to m eet the current building area requirements may be very difficult and will likely affect the historical fea­ tures of the building . This section does not prohibit the use of area increases from automatic sprinkler systems and frontage . 1204.3 Location on property . Historic structures undergo­ ing a chan ge of use to a hi gher-h azard category in accordance with Section 1011.6 may use alternative methods to comply with the fire-resistance and exterior opening protective req uirements . Such alternatives shall comply with Section 1201.2 . ❖ When changing to a higher hazard category , a build ­ ing should be evaluated for means to manag e the new or increased hazards . Literal code compliance may not be the only way , or the best way, to accom­ pli sh this objective in a historic building . 1204.4 Occupancy separation. Required occupancy separa­ tions of 1 hour may be omitted where the building is provided with an approved automatic spri nkl er system throughout. ❖ Substitution of automatic extinguishing systems for pa ss iv e protection is established as an acceptable procedure . 1204.S Roof covering. Regardless of occupancy or use group, roof-covering materials not less than Class C, where 2018 IEBC ®CODE and COMMENTARY 100722987 11a11;1u41m~r~11rn ,11t1, rn ~ tij 111 Copyright C 201s ICC. ALL RI GHTS RESERVED. Accessed by Erik Cortinas (erikc@cofairhope.com), (City of Fairhope) Order Number •100722987 on Jun 21, 2019 06:40 AM (Pon pursuiillt to License Agreement with ICC. No further reproduction or distribution authoriud. Single user only, copying iilld networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION JS A VJOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LI CENSE AGREEMENT, AND SUBJECT TO CM L AND CRIMINAL PENALTI ES THEREUNDER. tested in accordan ce with ASTM E l0 8 or UL 79 0, shall be penni tted where a fir e-retardant ro of coverin g i s required . ❖ Roof covering requir e me nts are a spread -of-fire iss ue : first, to prevent fire spread to the building in qu estion and , second , to ke e p burning brand s gener ­ ated by a fir e in that building from igniting other build ­ ings in a gen e ral conflagration . If a limited number of bu ilding s do not meet thi s requirement , however , th e hazard is not significantly increased . 1204 .6 Means of egress . Existin g door op enin gs and corrid or and stairway wi dths less th an those that would be acceptabl e for nonhis toric buildin gs under th ese provi sion s shall be approved, provi ded th at, in th e opini on of t he code official , th ere is sufficie nt wi dth and height fo r a person to p ass thro ugh the op enin g or traverse the ex it and th at the cap acity of the exit system is adequ ate for th e occ upant load, or where oth er operati onal contro ls to limit occupancy are approved by the code official. ❖ Thi s provi si on would permit the continu ed use of a stru cture that is no more hazardou s than before reha ­ bilitation , with minimum standards of usability . 1204.7 Door swing. Where approved by the code officia l, exis ting fro nt doors need not swin g in th e di recti on of ex it travel, provid ed that other approved exi ts hav in g suffi cie nt capacity to serve th e total occ up an t load are provided . ❖ Provi sion s for new con struction would require that e xit doors swing in the direction of e xit travel for an occupant load exc eeding 50 . Thi s section prescribe s a method by which existing e ntry doors can be allow ed to swing into th e building rather than in th e direction of e gre s s travel. 1204.8 Transoms. In corri dor walls re quired by these prov i­ sions to be fire -resistan ce rated, ex isting tran so ms may be maintained if fixe d in the closed position , an d fixe d wired glass set in a steel frame or oth er approved glazing shall be install ed on one sid e of th e tran som . Excepti on : Transo ms confo rming to Sec ti on 1203.4 shall be accepted . ❖ Th ese a lte rnative s would be us e d prim arily by non ­ res id e ntial occup a nci es, as resid e ntial occupancie s would use Section 1203.4 . 1204 .9 Finishes. Wh ere interi or finis h materi al s are requ ired to have a fla me spread index of Cla ss C or better, when tes ted in acc ordance with ASTM E84 or UL 723, exis ting noncon­ fonning materials shall be s urfaced wi th approved fire-r etar­ dan t pai nt or fi ni sh . Exception : Exi sting nonco nforming material s need not be surfaced wi th an approved fire -re tardan t p ai nt or finish wh ere the buil di ng is equi pped throug hout with an autom ati c sprinkler sy stem instal led in accordance with the Internati onal Buildin g Code an d th e nonconform in g materia ls c an be substan tiated as bein g hi storic in character. ❖ Thi s sectio n sets a minimum fl a me s pre ad ind ex for inte ri o r fin is hes in hi stori c structures . As a n option, HISTORIC BUILDINGS fire -retardant paint c an be u sed to make the curr ent historic material s comply . Fire retardant s hav e th e effect of slowing th e deve lopment and spre ad of fire . The exception , which require s an automatic s prinkler system , can be us ed where conditions are unsuitabl e for th e use of intumesce nt paint or varni s h or oth er fir e -r etardant finishes . 1204.10 One-hour fire-re sistant assemblies. W here I -hour fire-resi stance-rated constru ction is require d by-these provi­ sions, it n eed not be prov ided , regardl ess of construction or occupancy, where the exis ting wall an d ceiling finis h is woo d l ath and pl aster. ❖ The substitution of standard lath and pl aster con ­ struction for 1-hour fire -resistance -rated wall con ­ struction is a we ll -establi s hed alternative . Pre sse d tin ceiling s are an exampl e of this issue . Som e State Historic Pres ervation Office s (SHPO) may provid e additional guidanc e on thi s subject and alternatives . 1204.11 Stairways and guard s. Existi ng stairways shall co mply with the requirement s of these provi sion s . T he code official shall grant altern ati ves for stairways and guard s if altern ati ve st airways are fo und to be acceptabl e or are judged to meet th e intent of th ese provi sio ns. Existing stairways shall comply with Section 1203. Exception : For bu ildin gs less th an 3,000 square fee t (279 m2), exi stin g conditi on s are permitted to remain at al l stair­ ways and guards. ❖ Thi s provision gives an opportunity to a nalyz e the stairway s ' functionality as an exit, and to alter only tho se elements that are judged to be unsafe or inad e­ quate . The exception allows existing sta irway condi ­ tion s to re main for small e r building s, taking into a ccount th e s horte r time requir ed for e gress . 1204 .12 Exit signs. The code official may accept altern ative exit sig n locati ons where th e locati on of such signs wou ld damage the hi storic character of the buildi ng or stru cture . Su ch signs shall identi fy the exi ts and exit path . ❖ Sign s and exit path id entification are still re quir ed , but lo cation is pe rmitted to be fl e xibl e within limits of func ­ tionality . [BS] 1204.13 Exit stair live load. Existin g hi storic stairway s in b ui ldin gs chan ged to a Group R-1 or R-2 occ u pancy shall be accepted where it can be shown th at the stairway can sup­ p ort a 75 -pound s-per-squ are -foot (366 kg/m2) li ve load . ❖ In th e c ase of a building changed to a Group R occu ­ p ancy , th e like lihood is that stairs will be d es ign ed to a high e r c apacity th a n use would requir e . To s ub stan ­ ti at e th at lik e lihood , stru ctura l calcul ation s or oth e r data us ing th e structur a l prope rti es of t he ex isting sta ir con struction could be submitt ed to th e cod e offi ­ cial for approval. 1204 .14 Natural light. W here it is determi ned by the code offi cial th at compliance with th e natural ligh t req uirements of Section 10 10 .1 will lead to loss of his toric character or hi s- 2018 IEBC ®CODE and COMMENTARY 12-5 100722987 11 ~111 ■11J~••••111JJl.!ll~I] J] ·~•111, [~ 11 Copyright C 2ois ICC. ALL RI GHTS RESERVED. Accessed by Erik Cortinu (erikc@cofairhope.com), (City of Fairhope) Order Number ,100122987 on Jun 21, 20 19 06:40 AM (PDT) pursuant 10 License --~----!~!(I! __ -~!~}!_~ _ _ !!!!_ _ _ ~ -~. _ Agreement with ICC. No furthu reproduction or distribution authorized. Single user o nly, copying and networking prohibited. ANY UNAtrrHORIZED REP RODUCTION OR DISTRIBUTION JS A VIOLATI ON OF THE FEDERAL COPYRIGHT ACT AND THE LI CENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRI MINAL PENALTIES THEREUNDER HISTORIC BUILDINGS toric materials in the building, the existing level of natural lighting shall be considered to be acceptable . ❖ At the time the provisions requiring natural light in residential occupancies were enacted, they were a necessary public health reform . At this time, devia­ tions from these requirements would probably not have health consequences . SECTION 1205 STRUCTURAL [BS] 1205.1 General. Historic buildings shall comply with the applicable structural provisions for the work as clas sified in Chapter 4 or 5. Exceptions: 1. Th e code official shall be authorized to accept exist­ ing floors and existing live load s and to approve operational control s that limit the live load on any floor. 2 . Repair of substantial structural dama ge is not req uired to comply with Sections 405 .2.3 and 405.2.4. Substantial structural damage shall be repaired in accordan ce with Section 405 .2 .1. ❖ Any proposed work on historic buildings must comply with the structural provisions that apply, based on the nature of that work. In other words , the classification of any proposed work is the first consideration . Exception 1 authorizes the code official to accept existing floors and approve operational controls that limit the live load on any such floor . This could be achieved by posting load limit signs in conspicuous locations . Actual loads on floors are typically less than the code -required loads. This section permits consideration of the actual loads as opposed to the probabilistic loads used for new design . Section 1201 .2 allows alternative approaches through the evaluation and report. Exception 2 addresses the argument that hi storic buildings should not be subject to expensive and dis ­ ruptive wind and seismic retrofits when those retrofits are triggered by repairs . Alterations , additions , relo­ cations and changes of occupancy are all voluntary ; those projects should be subject to sensible upgrade trigger s, even for historic buildings, and the projects can be scoped and budgeted to accommodate these requirement s with due re gard for historic preserva ­ tion . Repairs, however , are not voluntary , so an upgrad e required by a repair might be at odds with the priorities of preservation. Not everyone will agree with this approach; after all, historic buildings are expected to provide adequate safety , too. But if his­ toric buildings s hould ever be exempt from the code's sensible wind and seismic retrofit triggers, it should be in the case of involuntary repairs . [BS] 1205 .2 Dangerous conditions. Condition s determin ed by the code official to be dangerous shall be remedied . Work 12-6 shall not be required beyond what i s req uired to remedy the dan gerous conditi on . ❖ The definition of "Dangerous" in Section 202 gives five conditions under which a building, a portion of a building or an individual structural component is con ­ side red dangerous . Any building or structural compo ­ nent that is determined to be dangerous presents an unacceptable risk to public safety . Section 115 .1 clar­ ifies that a building cons idered dangerous is deemed to be unsafe , and in order for an unsafe building to remain in place the building must be made safe . This section clarifies that in a historic building, any structura l repair , strengthening or replacement applies only to the specific component(s) or portion(s) necessary to correct the dangerous condition(s). SECTION 1206 RELOCATED BUILDINGS 1206.1 Relocated buildings. Foundations of relocated his­ toric buildings and structures shall comply with the Interna­ tional Building Code. Relocated historic buildings shall otherwise be considered a histori c building for the purposes of thi s code . Relo cated historic buildin gs and stru cture s shall be si ted so that exterior wall and opening requirements co m­ ply with the Internati onal Buildin g Code or with th e co mpli­ ance alternatives of thi s code . ❖ The foundation of a relocated building is a new struc­ ture ; there is no reason why it shou ld not comply with provisions for new construction. Compared with code provisions that treat a relocated building as a new building , however , the rest of the building is still treated as a historic structure. In relocation , siting is, to some degree , a new design decision . Relationship of walls and openings to property lines is, therefore, reasonably able to be brought into compliance with the fire separation requirements of the code Bibliography The following resource materials were used in the preparation of the commentary for this chapter of the code . 36 CFR. Parts 1190 and 1191 Final Rule , The Ameri­ cans with Disabilities Act (ADA) Accessibility Guide­ lines; Architectural Barriers Act (ABA) Accessibility Guidelines. Washington, DC : Architectural and Transportation Barriers Compliance Board , July 23 , 2004. 2010 ADA Standard for A ccessible Design . Washing ­ ton, DC : Department of Justic e, September 15 , 2010 . Standards for Treatm ent of Historic Properties. Wash­ ington , DC : Secretary of the Interior, 1992 . 2018 IEBC ®CODE and COMMENTARY 100722987 Copyright C 2018 ICC. ALL RIGHTS RESERVED. Accessed by Erik Cortina.s (erikc@cofairhope.com), (City of Fairhope) Order Num~r •100722987 on Jun 27, 2019 06:◄ 0 AM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VJOLATION OF THE FEDERAL COPYRIGIIT ACT AND THE LI CENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER