THE BUILDING ENVELOPE: Lecture 3 Building Codes and Standards

MODEL BUILDING CODES Establish standard of practice Represent “minimum” standards Must be adopted by local authority to be “legal”

MODEL BUILDING CODES April 2000 : Uniform Building Code Standard Building Code BOCA/Basic Building Code became The International Building Code

INTERNATIONAL BUILDING CODE One national consensus model code Based on national consensus standard (ASCE 7) Will become standard of practice in foreseeable future as local jurisdictions formally adopt the IBC

INTERNATIONAL RESIDENTIAL CODE Replaces CABO “One- and Two-Family Dwelling Code” Residential buildings where V > 110 mph must be designed for loads in ASCE 7 Requires that ~ one-half of new residential buildings in U.S. be “engineered”

ASCE 7 “Minimum Design Loads for Buildings and Other Structures” (ASCE, 2002) National consensus standard Captures modern wind engineering technology Addresses factors judged to affect significantly the pressures that act on buildings in windstorms

ASCE 7: FACTORS THAT AFFECT PRESSURE wind speed (V) terrain (K z ) topography (K zt ) wind direction (K d ) wind gusts (G) building geometry (C p ) relative importance of the building (I).

NATIONAL CONSENSUS STANDARDS ASCE 7: Minimum Design Loads ASTM: Wind Borne Debris AISC/AISI: Steel Construction ACI: Reinforced Concrete NFPA: Timber Construction NCMA: Concrete Masonry MBMA: Metal Buildings AAMA: Architectural Glazing

LOCAL BUILDING CODES Formal enactment of laws or ordinances are necessary for legal enforcement of Local Building Codes State Building Codes County Building Codes Municipal Building Codes Insurance Building Codes

PERFORMANCE AND PRESCRIPTIVE CODES Performance Codes: Require the designer to meet specific performance standards (e.g., a specific design wind speed) Prescriptive Codes: Prescribe construction details for the builder (i.e., if the builder conforms the building is deemed to be in compliance)

THE "EITHER/OR" OPTION The IRC and ASCE 7 offer the designer an two options: Design for (1) windborne debris (i.e. window protection) or (2) for internal pressure Many designers opt for Option 2 Option 2 is often short sighted

BEYOND CODE MINIMUMS IBC/IRC and ASCE 7 establish minimum requirements Designer has responsibility to assess special project conditions that may warrant attention beyond code minimums Special design requirements may be established