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Fire Resistive Construction

Construction Class 6

Overview

Fire Resistive Construction

Overview

This Construction Brief will give you an overview of Verisk's Construction Class 6 – fire-resistive construction. When you've completed this course, you will know what a Verisk report means when it says a building is fire-resistive construction. And you'll understand why a particular structure is—or isn't—fire-resistive.

Walls:

  • Solid masonry, including reinforced concrete not less than four inches thick
  • Hollow masonry not less than 12 inches thick
  • Hollow masonry less than 12 inches thick, but not less than eight inches thick with a listed fire-resistance rating of not less than two hours
  • Assemblies with not less than a two-hour fire-resistance rating

No results

Floors and roofs:

  • Reinforced concrete not less than four inches thick
  • Assemblies with not less than a two-hour fire-resistance rating
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Structural metal supports:

  • Horizontal and vertical load-bearing protected metal supports—including prestressed and posttensioned concrete units—with not less than a two-hour fire-resistance rating

The exterior bearing walls and load-bearing portions of exterior walls must be of noncombustible materials or of masonry, but exterior nonbearing walls and wall panels may be slow burning, combustible, or with no fire-resistance rating.

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Solid masonry

Fire Buildings

Hollow masonry

Noncombustible Materials

Exterior walls of noncombustible materials

Pre- and post-tensioned concrete units

  • Both pre- and post-tensioned concrete units have steel cables installed in the concrete to provide tensile strength. With pre-stressed concrete units, builders pull the cables tight before pouring the concrete and release them as the concrete cures. With post-tensioned concrete units, builders pull one end of the cable tight after pouring the concrete.
Posttensioned Concrete Units

Post-tensioned concrete units

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Prestressed concrete units

Advantages of fire resistive construction

Advantages Of Fire Resistive Construction

Advantages of fire resistive construction

  • Uses noncombustible materials
  • Allows greater height and area than other construction classes
  • Uses load-bearing members or assemblies that resist damage from fire

Disadvantages of fire resistive construction

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Disadvantages of fire resistive construction

  • Expensive to construct and repair, provides a false sense of security

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