Design Criteria

Residential Design Criteria*

Criterion	Specification
Ground snow load	15 PSF
Wind speed	118
Seismic design category	A
Weathering	Severe
Frost line depth	12 IN
Termite	Moderate to heavy
Winter design temperature	22ºF
Ice barrier underlayment required	No
Flood hazards	May 2, 1977
Air freezing index	150
Mean annual temperature	59ºF

*Design criteria for buildings constructed in accordance with the Virginia Residential Code. For all other buildings, see Chapter 16 of the Virginia Construction Code (PDF).