Building and Infrastructure Construction

Frame Construction (ISO Class I, IBC Type V)

Frame construction is ISO Class 1. ISO Class 1 encompasses IBC Type VA and IBC Type VB. Regardless of whether the IBC classification is A (protected) or B (unprotected) the ISO Class is 1.

1. Note the elements of frame building construction:
   • Frame buildings are buildings with exterior walls, floors, and roofs with combustible construction — or buildings with exterior walls of noncombustible or slow-burning construction with combustible floors and roofs.
   • Frame buildings generally have roof, floor, and supports of combustible material, usually wood, and combustible interior walls.
   • Two variations on frame construction don’t change the construction class:
     • Masonry veneer (brick veneer)- Masonry veneer is thin layers of brick, stone, or stucco, used for appearance purposes rather than structural support.
     • Metal clad – A building with a metal exterior wall may not look like frame construction, but when the metal skin is attached to wood studs and joists, ISO classifies the building as frame.
   • Other Conditions That Lead to Classification as Frame Construction include:
     • Metal walls or floors sheathed with combustible materials
     • Metal floors or roofs with combustible insulation or ceiling material attached to the underside or within 18 inches of horizontal supports
     • Composite assemblies of noncombustible materials with combustible materials
2. Be familiar with the advantages of frame construction:
3. Frame construction offers these advantages:
   • easy to erect and alter
   • economical
   • versatile
   • performs well in Earthquake areas – can move
4. Be familiar with frame construction disadvantages:
5. Frame construction has these disadvantages:
   • • fire can spread rapidly
     • highly damageable
     • may become unstable in a fire
     • may include enclosed spaces where fire can spread undetected