I- Beam

See “S” Shape

Ice Dam

A buildup or ice which forms a dam on the roof covering along the eave of the building.

Impact Load

A dynamic load resulting from the motion of machinery, elevators, craneways, vehicles, and other similar moving forces. See Auxiliary Loads.

Impact Wrench

A power tool used to tighten nuts on bolts.

Importance Factor

A factor that accounts for the degree of hazard to human life and damage to property.

Insulation

Any material used in building construction to reduce heat transfer.

lnternal Pressure

Pressure inside a building.