B-01 — environmental loads

Environmental Loads

Snow, wind, and seismic — the loads that vary by location. Where you build determines which ones govern and by how much.

SEISMIC SNOW WIND SNOW + WIND HURRICANE AK

click a region to explore its load profile

← select a region
to see its load profile
load profile

ASCE 7 translates natural hazards into design loads: wind speed → pressure, ground acceleration → base shear, ground snow → roof load.
Every environmental load starts with a map (geographic hazard), gets modified by site-specific factors (exposure, soil class, building importance), and becomes a force or pressure the structure must resist.
key concepts
overview Geography sets snow, wind, and seismic demands

Environmental loads — snow, wind, and seismic — are set by geography. ASCE 7 maps translate location into design demands that every structure must resist.

one code, all the hazards ASCE 7 translates natural hazards into design loads

ASCE 7 (Minimum Design Loads and Associated Criteria for Buildings) is the single document that translates natural hazards — wind, earthquake, snow, rain, ice — into design loads that engineers can use. It doesn't tell you how to size a beam; it tells you what that beam has to resist. Every structural design in the US starts with ASCE 7. The current edition is ASCE 7-22.

from maps to numbers Hazard maps plus site factors yield design loads

The process: look up your site on the hazard maps (wind speed, seismic spectral acceleration, ground snow load), apply modification factors for your building's specific conditions (exposure category, site class, importance factor, topographic effects), and out comes a design load in psf or kips. The maps embed decades of meteorological and seismological data into a single contour line.