Go to Home Page           Conservationtech.com, Building Conservation Technology

SITE INDEX | BASE-ISOLATED HOUSE PROJECT | PUBLICATIONS | PHOTOGRAPHS | EXHIBITIONS | RESUME & CONTACT INFO | Site info

Chapter 1: Buildings

1C: RISK ASSESSMENT - Year of Construction

Year of construction (from FEMA 154-p129 for benchmark years)

This chart provides the benchmark years for the three principle model codes.  Before allowing credit for structures later than these benchmarks, one must ascertain that the local codes reflected these provisions at the that time.  The code that is the model code for most of the area in the United States subject to high seismicity is the Uniform Building Code, (ICBO), which was also the first to reflect increased requirements for seismically resistive design.  When using D6, The Rapid Visual Survey, it is important to determine when the particular code was adopted and enforced locally.

Model Building Seismic Design Provisions
Building Identifier NEHRP UBC BOCA SBCC
W1 LIGHT WOOD FRAME 1985 1976 1992 1993
W2 HEAVY TIMBER/OVER 5,000 SF. 1985 1976 1992 1993
S1 STEEL MOMENT RESISTING FRAME (MRF) ** 1994 ** **
S2 BRACED STEEL FRAME 1991 1988 1992 1993
S3 LIGHT STEEL FRAME * * * *
S4 STEEL FRAME WITH CONCRETE SHEAR WALLS 1985 1976 1992 1993
S5 STEEL FRAME WITH UNREINFORCED MASONRY (URM) INFILL * * * *
C1 REINFORCED CONCRETE (RC) MRF 1985 1976 1992 1993
C2 RC FRAME WITH SHEAR WALLS 1985 1976 1992 1993
C3 RC FRAME WITH URM INFILL * * * *
PC1 RC TILT-UP 1985 1997 * *
PC2 PRECAST RC FRAME * * * *
RM1 REINFORCED MASONRY WITH FLEXIBLE DIAPHRAGMS 1985 1997 * *
RM2 REINFORCED MASONRY WITH RIGID DIAPHRAGMS * 1976 1992 1993
URM UNREINFORCED MASONRY * 1991 * *

* Indicates no benchmark year (i.e., no buildings of this type may receive a positive age modifier in the RVS analysis.) 

** Contact local building official for benchmark year.

** Local provisions for wood construction need to be compared to 1949 UBC to determine benchmark year.

NEHRP = National Earthquake Hazards Reduction Program, FEMA 302, Recommended Provisions for the Development of Seismic Regulations for New Buildings.

UBC = International Conference of Building Officials, Uniform Building Code.

BOCA = Building Officials and Code Administrators, National Building Code.

SBCC = Southern Building Code Congress, Standard Building Code.

One of the key issues that must be addressed in the planning process is the determination of (1) the year in which seismic codes were initially.  Therefore, as part of this review process, the user should identify (1) the year in which seismic codes were first adopted and enforced in the area to be screened, (2) the "benchmark" year in which significantly improved seismic code requirements were adopted for each building type, and (3) the year in which the community adopted seismic anchorage requirements for heavy cladding. If the RVS authority in high and moderate seismicity regions is unsure of the year(s) in which codes were initially adopted, the default year for all but one building type is 1941 (the default year specified in the HAZUS criteria; NIBS, 1999). The one exception is PC1 (tilt-up) buildings, for which it is assumed that seismic codes were initially adopted in 1973, the year in which wall-diaphragm (ledger) connection requirements first appeared in the Uniform Building Code (ICBO, 1973).

During the review of the Data Collection Form, the user should confer with the chief building official, plan checkers, and other design professionals experienced in seismic design to identify the years in which the affected jurisdiction initially adopted and enforced seismic codes (if ever) for the building lateral-force-resisting structural systems considered by the RVS procedure. Since municipal codes are generally adopted by the city council, another source for this information, in many municipalities, is the city clerk's office. In addition to determining the year in which seismic codes were initially adopted and enforced, the RVS authority should also determine (1) the benchmark years in which substantially improved seismic codes were adopted and enforced for the various lateral-load-resisting systems and (2) the year in which anchorage requirements for cladding were adopted and enforced.

Return to RISK ASSESSMENT list

 

HOME PAGE | SITE INDEX | BASE-ISOLATED HOUSE PROJECT | PUBLICATIONS | PHOTOGRAPHS | EXHIBITIONS | RESUME & CONTACT INFO | Site info

Website by

Randolph Langenbach

M-Arch (Harvard), Dipl.Conservation (York, England)


FAX: 801-730-1616

Writings and photographs found on this website is Randolph Langenbach and other authors. For use permission, write to the address above.

Please send your reactions, comments or questions regarding this website to the Email address above