Chapter 29: Building Codes & Regulations

Chapter 29: Building Codes & Regulations HISTORY OF BUILDING CODES • • Babylonian Law of Hammurabi, 2000 – death to builder if constructed house coll...
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Chapter 29: Building Codes & Regulations HISTORY OF BUILDING CODES • •

Babylonian Law of Hammurabi, 2000 – death to builder if constructed house collapsed and killed owner Henry Fitz-Elwyne Assoze of Buildings, London, 1189: Thached roofs prohibited Party walls specified



Great Fire of 1666: parlament established: Classes of buildings Types of materials allowable Established fees for cost of inspections Metropolitan building act, 1844: took above and revised: To regulate height Occupancies Establish a building official USA codes prompted by fires and diseases in urban areas (NYC) 1625: first code for settlement of New Amsterdam regulated roof coverings to protect from chimney sparks 1871: Chicago fire prompted insurance agencies to see benefit of codes 1905: nat’l Board of Fire Underwriters first model fire code = first National building Code Result was three model building codes BOCA: Building Official Conference of America UBC: Uniform Building Code SBC: Standard Building Code Combined in 1990 into single International Building Code 2000, first publication





BUILDING REGULATIONS State and Federal Regulations • •

Fed agencies regulate military and prisons Safety-glazing requirements issued by Consumer Products Safety Commission (CPSC) ADA: removal of barriers for the physically disabled Requirements based on American National Standard Institute (ANSI) ICC/ANSI A117.1: Accessible and Usable Buildings and Facilities ADA is not a code, but a civil rights legislation

Local Regulations •

Local codes may include amendments to the model code in use pertaining to concerns of geographical region

BUILDING CODES Legal Basis of Codes •

• • •

Authority for adopting and enforcing codes is of police powers given to state by 10th amendment to constitution Each state in turn may retain powers or delegate to lower levels of gov’t Adopting and enforcing codes varies among states Codes typically adopted and enforced by local gov’t Few states adopt a model code state wide Before construction: enforced as permit process where architect submits to authority having jurisdiction (AHJ) Durring construction: AHJ conducts inspection

Model Building Codes • • • • • •

• • • •



Written by experts w/o reference to geographical area Adopting is a workable code w/o difficulty & expense of writing own Can have provisions needed to suit particular requirements of municipality If city or state writes own code, usually based on a model code Exceptions: new York & Chicago Primary model code: IBC of 2000 published by the International Code Council (ICC) Three model codes still used: Uniform Building Codes (UBC): Western & central US, published by International Conference of Building Officials (ICBO) BOCA National Building Code: Northeast, published by Building Officials and Code Administrators International (BOCA) Standard Building Code (SBC): Southern US, published by Southern Building Code Congress International (SBCCI) Life Safety Code: published by Nat’l Fire Protection Association National Building Code of Canada (NBC) Nat’l Fire Protection Association (NFPA): written own code NFPA 5000 Building Code: 2002 IBC: prescriptive as opposed to performance based Describes specific materials and methods Describes how a building components must be designed as opposed to how it is supposed to function Codes written to protect health, safety and welfare of public Written on least acceptable risk

Adjuncts to Building Codes •

• •

Other codes published by the ICC International Residential Code International Fire Code International Mech Code International Plumbing Code International Zoning Code National Electrical Code (NEC): elec code used by all jurisdictions, published by Nat’l Fire Protection Assoc (NFPA) Model codes make use of industry standards developed by trade associations Gypsum Association Gov’t agencies Standards writing associations: adopted by reference American Society for Testing and Materials (ASTM) National Fire Protection Associations (NFPA) American Nat’l Standards Institute (ANSI)

TESTING AND MATERIAL STANDARDS • • •

Standards developed by trade associations Standards have no legal standing Only referred to in a code that is adopted by gov’t jurisdiction

Standard Writing Organizations •

American Society for Testing and Materials (ASTM): publishes standards and test procedures that prescribe how Test apparatus must be set up How materials must be prepared for test Length of test







Nat’l Fire Protection Association (NFPA): standards related to the causes and prevention of destructive fires Sprinkler systems, fire extinguishers, hazardous materials, fire fighting NFPA publishes own code NFPA 5000 Other standards writing organizations: ASHRAE Illuminating Engineering Society (IES) Gypsum Assoc (GA) American Concrete Institute (ACI)American Iron and Steel Institute (AISI) American Institute of Timber Construction American national Standards Institute (ANSI): does not develop or write standards, but approves those developed by other organizations and works to avoid duplications

Testing Laboratories • When standards describe a test procedure, a Nat’l Recognized Testing Lab (NRTL) must perform test An independent lab recognized by OSHA to test products to specifications of applicable standard Most well known NRTL is Underwriters Laboratory (UL) Listed label: When product is successfully tested, passed the safety test and is manufactured under UL follow-up services program Classified label: samples tested for certain uses only and must cary statement specifying conditions tested for Most common uses of UL testing is for doors and other opening penetrations UL 10B Fire Test of Door Assemblies Results of tests are listed in UL’s Building Materials Directory Types of Tests and Standards • Codes indicate what tests or standards material must satisfy ASTM C36, Standard Specification for Gypsum Wallboard • Most important tests are those that rate ability of a construction assembly to prevent passage of fire and smoke from one space to another ASTM E-119 • Standard Method of Fire Tests of Building Construction and Materials • Overall, test evaluates assemblies ability to prevent passage of fire, heat and hot gases for a given amount of time • Tests sample of wall, floor/ceiling assembly applying fire on one side • Part 1: Measures heat transfer, determines temp at which the surface of adjacent materials on side of assembly not exposed will combust at • Part 2: Hose Stream test that uses a high pressure hose stream to simulate how well assembly stands up to impacts from falling debris and cooling and eroding effects of water • Assemblies tested given a rating according to time 1-hr 2-hr 3-hr 4-hr • Doors and other openings 20-min 30-min 45-min NFPA 252 • • • •

NFPA 252, Fire Tests of Door Assemblies Evaluates ability of a door assembly to resist passage fo flame, heat and gases Time base fire endurance rating & hose stream Test determines if door will stay within its frame when subjected to standard blast from fire hose

NFPA 257 • NFPA, 257, Standard on Fire Test for Windows and Glass Block Assemblies • Degrees of fire protection in units of time for window openings in fire resistive walls • Flammability tests for finishes • ASTM E-84, NFPA 265 and NFPA 286 • If a material is flammable and if it simply burns with apply heat or supports combustion (adds fuel to fire)

ASTM E-84 • • • • •



ASTM E-84, Standard Test Method for Surface Burning Characteristics of Building Materials Also known as Steiner tunnel test Most common Rates the surface burning characteristics of interior finishes Can be used to generate a smoke developed index Class A (I): 0-25 most resistant Class B (II): 26-75 Class C (III): 76-200 Codes specify min flame spread for various occupancies

NFPA 265 • • • •

NFPA 265, Room corner test Determines contribution of interior wall and ceiling coverings to room fire growth Simulate real conditions Textile coverings applied to three sides of and 8’ x 12’ x 8’ room Ignition source provides heat output of 40 kW for five min and then 150 kW for 10 min Passes if: Flame does not spread to ceiling during 40 kW exposure and No flashover and no spread of flame to outer extremity during 150 kW exposure

NFPA 286 • • •

NFPA 286, Standard Method of Fire Tests for Evaluating Contribution of Wall and Ceiling Interior finishes to Room Fire Growth: Evaluates materials other than textiles to address concerns with finishes that do not remain in place During the E-84 test Evaluates extent finishes contribute to growth in a room by assessing heat and smoke released, combustion products release and potential fire spread beyond room

FIRE RESISTIVE STANDARDS Construction Materials and Assemblies • • •

Classification of fire resistance a material or assembly must have Specified in hourly rating determined by ASTM E-119 for walls ceilings/floor assemblies, columns, beam enclosures, etc Any penetrations in fire resistive barrier must also be fire rated Doors windows, ducts Duct protected w/ fire dampers w/ fusible link that closes a louver to maintain wall rating

Types of Fire Resistance Rated Walls and Partitions •

Fire partition: 1-hour fire resistance rating where: Walls separating dwelling units Walls separating guestrooms in Groups R-1 occupancies (hotels) Walls separating tenant spaces in covered malls Corridor walls Fire partitions must provide continuous barrier that extend from floor to roof/floor slab Openings in fire partitions min 3/4-hr except for corridors which must protect 20-min Continuous slab-to-slab is best w/ passive control of smoke and fire w/o relying on ceiling assembly. Also easies and cost effective



Fire barrier: designed to restrict spread of fire, confine it to limited area and afford safe passage for egress To enclose vertical exit enclosure Separate different occupancies in mixed use Separate single occupancies into different fire areas Provide barrier where required by code Must be cont from floor to slab Must have resistance rating greater than 1-hr Openings protection varies depending on rating of barrier May range from 20-min to 3-hr Max aggregate width of 25% of length of wall Single opening cannot exceed 120 ft2 Exceptions: If adjoining area sprinklered Fire doors Not limited if opening protective assembly has been tested according to ASTM E-119 and has fire resistance rating equal to or greater than that of wall



Fire Wall: used to separate a single structure into separate construction types 2 to 4-hr rating Continuous from foundation thru roof One side can collapse w/o affecting structural stability of adjacent



Smoke barrier: membrane w/ min fire resistive rating of 1 hour Openings of 20-min

Finishes • • • • • •

Second type of fire resistive classification: single layers of finish material rated according to ASTM E-84 and use is restricted to certain areas of buildings Purposes: to control flame spread rate to limit amount of combustible material Traditionally: E-84 exclusive for interior finishes but IBC allows use of finish materials with exception of textiles if in accordance with NFPA 286, Std Method of Fire Tests for Evaluating Room Fire Growth Contribution of Wall and Ceiling Interior Finish Textile coverings must either be rated as Class A according to ASTM E-84 and be protected by an automatic sprinkler system or must meet requirements of NFPA 265 NFPA 253, the Flooring Radiant Panel Test: tests amount of radiant energy needed to sustain flame is measured and defined as critical radiant flux Two classes Class I: critical radiant flux of not less than .45 W per cm2 Required in vertical exits, egress passage and exit corridors in Group I-2 and I-3 (hospitals nursing homes detention facilities Class II: critical radiant flux of not less than .22 W per cm2 Required in vertical exits, egress passage and exit corridors in Groups A, B, E, H, I -4, M, R-1 and S occupancies

Decorations and Trim • • • •

Materials in occupancies of Groups A, E, I, or R-1 and dormitories in Group R-2 must be flame resistant and pass NFPA 701 vertical ignition test Amount of non combustible decorative materials is not limited byt the amount of flame resistant materials is limited to 10% of the aggregate area of walls and ceilings except in A occupancies where it is limited to 50% of building if fully sprinklered Interior trim: min Class C flame spread index Combustible trim excluding handrails and guardrails cannot exceed 10% of aggregate wall

ADMINISTRATIVE REQUIREMENTS OF BUILDING CODES •

Chapter of codes that outlines provisions Codes applicable Powers of building official Permit process Info req’d on documents Fees for services How inspections are handles Kinds of inspections are req’d Requirements for CofO Provisions for appeal

REQUIREMENTS BASED ON OCCUPANCY • •

Occupancy: refers to type of use for a building Occupancy group varies by fire protection requirements area and height limitations type of construction restrictions, means of egress

Occupancy Groups •

A Assembly -

• • •

F-1: Factory moderate hazard F-2: Factory low hazard

H Hazardous I Institutional -

• •

assembly w/ fixed seats assembly for food and drink assembly for worship,recreation or other assembly for indoor sports Assembly for outdoor sports

B Business E Education F Factory & industrial -

• •

A-1: A-2: A-3: A-4: A-5:

I-1: I-2: I-3: I-4:

16 ambulatory people on 24hr medical care on 24hr basis >5 people restrained Daycare for >5 adults or infants

theatres, live performance bars, restaurants libraries, museums, conf rooms (+50) arenas stadiums offices, banks, education above 12th grade Post office grade schools & day care if > 5 kids & > 2.5 yrs old see code see code see code assisted living, group home, convalescent facilities hospitals, skilled care ails, reformatories daycare for infants Dept. stores, markets, retail, sales rooms

M Mercantile R Residential (must use International Residential Code) -

R-1: residential for transient lodging R-2: residential with 3+ units R-3: 1-2 units w/ attached uses or child care 5 occupants but < 16

Hotels apartments, dorms, convents

small assisted living See code

• •

S Storage U Utility



Occupancy class determines: max. area, # floors allowed how buildings must be separated from together structures occupant load egress design interior finish requirements fire partitions and barriers dire detection & suppression venting and sanitation requirements

See code

Mixed Occupancy and Occupancy Separation • •

When building contains two or more occupancies Each occupancy must be separated w. a fire barrier of hourly rating defined by code

Accessory and Incidental Uses • • •

Accessory use area: space used in conjunction w. main occupancy but does not exceed 10% of floor area of main use Do not need to be separated Example: gift shop in hospital Incidental use area: incidental to the major occupancy and classified the same as the major occupancy. But by code must be separated with fire barrier Separation requirements given in IBC table 302.1.1 When table allows a sprinkler system to substitute for a fire barrier, incidental use area must be separated by smoke barrier and sprinklers only have to be in incidental use area. Doors must be self closing

CLASSIFICATION BASE ON CONSRUCTION TYPE • • • • • •

• •

Based on fire resistance rating of its major construction components Purpose is to protect the structure from collapse and to divide building so fire will be contained ong enough to evacuate Type I & II– non combustible Types III, IV & V – combustible Requirements for ext, nonbearing walls are based on distance from building to property line, type of construction and occupancy group Combination of occupancy groups & building type limits area and height. Example: Type I buildings of any occupancy can be unlimited area and height while Type V are limited to only a few thousand square feet and one to three stories, depending on occupancy. Limiting height and area based on occupancy & construction type recognizes difficulty to fight fires Fire zone: urban areas divided into zones representing degree of fire hazard base on density, access for fire fighting and existing building height For renovation knowing construction type is important if major changes Example: of occupancy is changed from a ‘B’ to an ‘A’, architect must know construction type to verify if max area is not exceeded If it is fire wall may be needed or sprinklers

Allowable floor Area and Heights of buildings •

• •





Ch. 5 of IBC establishes max height and area based on construction type & gives allowable occupancy and conditions which height and area may be increased Concept: more hazardous = smaller it should be (SEE Table 29.7 & 29.2) If bldg is equipped with sprinkler, area and height can be increased One story can be tripled in area Multistory can be doubled in area Max height increased by 20’ No stories increased by 1 If more than 25% perimeter is located on public way, area may be increased according to various formulas Exception: Group H, Divisions 1,2and 5 (hazardous occupancies) Allowable height and building area table (29.7) used: If occupancy and construction type are known, find intersection of “occupancy” row and “type” column = permitted area or height Then able to increase the area according to the percentages allowed for sprinklers and perimeter open space Part of pre-design phase Occasionally, design for occupancy different than original occupancy. If existing not large enough to accommodate new occupancy, project may be infeasible

-

Example: 12,00 ft2 Type V bldg formerly low hazard (F-2). To be remodeled into nightclub (A-2). IBC states max allowable floor area for F-2 is 13,000 & 6,000 for A-2, entire area cannot be used as a nightclub unless adding fire walls. Portions separated are considered separate buildings as long as requirements for fire wall met. 4hr for H-1 & H-2 2hr for F-2, S-2, R-3 and R-4 3hr for others

Location On Property • •

Ch 6 of IBC – Requirements for siteing of buildings relative to adjacent property Resistance of exterior nonbearing walls based on distance from property lines

MEANS OF EGRESS The Egress System • •

• • • •

Means of Egress: cont & unobstructed path of vertical & horizontal egress travel from any point in building to a public way Parts: Exist access Exit Exit discharge Must lead to a public way unobstructed from ground to sky & is permanently appropriated to public Clear width of not less than 10ft Exit Access: portion of the means of egress that leads to the entrance to an exit Exit: portion that provides protected path of egress between exist access and the exit discharge. Fully enclosed and protected from al other interior spaces by fire resistance rated construction Exit discharge: portion between termination of exit and public way. Typically include portions outside exterior walls Exterior discharge may include lobbies if exit door clearly visible, level of discharge is sprinkelered, area of discharge is separated by same fire resistance as exit enclosure

Occupant Load • • •

Occupant load: number of people code assumes will occupy a given building Assumes certain uses will be more packed with people exiting should respond accordingly IBC requires load be established by larges number by: Actual number Auditorium with fixed seating Taking area in square feet and dividing by an occupant load Most common method Occupant load factor: floor area presumed to be occupied by one person When occupant load from an accessory space exits through a primary space, the egress facilities from the primary space occupant load must include the occupant load of the primary space plus the occupant load of the accessory space Requires occupant loads should be cumulative as occupants exit thru intervening spaces to an ultimate exit Mixed occupancies each area calculated then added together Example: occupant load for restaurant dining room that is 2,500ft2 “assembly w/o fixed seats” load factor of 15ft2 dividing 15 into 2500 = 167 persons Example: occupancy load for office w/ gross area of 3700ft2 & two training classrooms of 1200ftt ea -business area had occupant load factor of 100 gross, so 3,700 divided by 100 = 37 persons -classrooms load factor of 20, two classrooms of 1200 five a total of 2400ft2 divided by 20 = 120 persons for the two classrooms -157 total persons

Required Number of Exits • •

Based on occupant load and occupancy of a space IBC requires two exits when occupant load exceeds number given in: Max Occupancy Load Spaces With One Exit Occupancy A, B, E, F, M, U H-1, H-2, H-3 H-4, H-5, I-1, I-3, I-4, R S

• •

Max occupant load 50 3 10 30

Exceptions: second story of an apartment w. only four units and max travel distance of 50’ Large occupancy loads: three exits when occupant load is between 501 & 1000 Four exits requires for 1000+ occupants

Common Path of Egress Travel •

Common path of egress travel: portion of exit access that occupants traverse before two separate and district paths of egress are available Two exits are not required based on occupant load if common path exceeds 75’, then two exits from space required Distance increased to 100’ in occupancies B, F and S if building sprinklered

Maximum Travel Distance •

Exit access travel distance: distance that an occupant must travel from the most remote point in the occupied portions of the exit access to the entrance to the nearest exit



(INSERT Table 29.10)

Separation of Exits • •

When two exits are required, they must be placed a distance apart equal to not less than one half the length of the max overall diagonal dimension of the building or area to be served if three or more exits, two must conform to the one half diagonal distance rule, third a reasonable distance apart

Width of Exits •

Required max width determined by multiplying the occupant load by appropriate factor given in table 1005.1 of IBC, resulting number is minimum total width in inches In standard buildings .3 for stairways .2 for egress components In sprinklered buildings factors are: .2 for stairways .25 for egress components Example: if occupant load is 157, min width of corridor in office unsprinklered building, multiply 157 by .2 = 31.4” However: elsewhere in codes, min width serving an occupant load greater than 50 is 44”

Exiting Through Intervening Spaces • •

Egress can pass thru an adjoining room provided that the room is accessory to the area served and the adjoining room is not an H occupancy Must be a discernible path of egress travel to an exit

CORRIDORS •





Corridor: fully enclosed portion of an exit access that defines and provides a path of egress travel to an exit Purpose is to provide space w/ limited choices as to paths or directions of travel When two exits laid out so possible to travel in two directions to an exit Width of exit must not be less than 44” Exceptions: 24” – Access to electrical, mech and plumb equipment 36” – Where occupant load is 50 or less 36” - Within a dwelling unit 72” – Group E occupancies serving occupant load of 100 or more 72” – Group I occupancy corridor serving health care centers 96” – Group I-2 bed movements However: min width determined by code should be verified w/ min dith req’d by ADA Corridor cannot be encroached upon except: Door opening into path of egress travel can reduce the required width up to one half during curse of the swing but when fully open the door cannot project more than 7” Horizontal projections such as handrails trim, fixtures and lights can project horizontally max of 4”

Corridor Construction •

Slab to slab construction exceptions: Group E classrooms and assembly rooms have half of their required egress loading directly to the exterior at ground level In a dwelling unit In open parking garages Group B occupancies that only require one exit

Openings in Corridors • •

Doors, glazing and fire shutters to have min rating of 20min Total area of fire protection rated glazing between rooms and corridors cannot exceed 25%

Corridor Continuity • •

`When corridor required to be fire rated continuous to exit Exceptions: Corridors may pass thru foyers, lobbies and reception as long as these spaces are rated as adjacent corridors Corridors in fully sprinklered Group B to pass through enclosed elevator lobbies

Dead Ends • •

Dead end: occupant has only one choice of direction leading to an exit Code allow dead ends if the do not exceed 20’ Exceptions: Not limited in length where length is less than 2.5 times the least width of the dead end corridor D and F occupancies ma have 50’ dead end corridors if entire building is sprinlered 50’ long in group I-3

DOORS • • • • •

Potential obstruction to egress Must be distinguishable from adjacent construction Recognizable as means of egress Cannot be covered w/ reflective materials Cannot be concealed with decoration

Size of Doors •

Must be sufficient for occupant load (32” min)

Door Swing • • • • • • • •

Pivoted or side hinged to ensure familiarity to user Special doors not considered exit Some revolving allowed if leaves collapse & at least one conforming door adjacent Swing in direction of travel when area served has occupant load of 50 or more Cannot swing into a required travel path. If so, door must be recessed in cove Doors without closers: max opening force of 5lbf Doors with closers: max opening force of 15lbf Max allowable force to set door in motion is 30lbf Door must swing to fully open position

Fire Resistive Rating Requirements •

Egress doors in fire rated partitions required to have fire rating

STAIRWAYS Exit Stairways • • •

Completely enclosed In buildings four or more stories in height, must have 2hr rated walls Buildings less than four stories (including mezzanines) 1hr rating

Requirements for All Stairways • • • • • • • • • •



Serving an occupant load of more than 50: min 44” or Occupant load X .3 or .2 (greater) Serving an occupant load of less than 50: min 36” Handrails may project 4 1/2” If accessible means of egress: min 48” Risers min 4”, max 7” (R-2: max riser = 7 3/4”) Treads min 11” (R-2: min tread = 10” Winding, circular and spiral used as exits in R-3 occupancies Landings at top and bottom Min width = width of stair, but need not exceed 48” Max distance between landings is 12’ vertically Handrails: both sides, intermediate required fo all portions of stairs for egress are within 30” Stairways wider than 5’ must have intermediate Top = 34” – 38” Must extend not less than one tread beyond top and bottom riser Ends must be returned 1 1/4” – 2” dia, easily gripped and 1 1/2” between it and wall Nosing: 1/2” radius max 1 1/4” max projection 1/2” radius w/ 60° angle to a max projection of 1 1/4”

OTHER CODE REQUIREMENTS High Rise buildings •

High-rise: occupied floors more than 75’ above fire dept vehicle access

Guard (guardrails) • • • • •

Guard: to prevent falls from elevated area Where 30” or more above floor Min 42” high 4”dia sphere cannot pass up to 34” must resist a load of 50lbf/ft

Fire Detection and Suppression • •

Single smoke detector in residence Elaborate in high rises including communication devices & audio & visual alarms for hearing impaired

Sound Ratings •

IBC requires wall, floor/ceiling assemblies in residential occupancies: Min sound transmission class (STC) of 50 (45 field tested for walls Min impact insulation class (IIC) for floors of 50 (45 field tested)