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fire resistive construction (ISO)

Fire resistive construction is one of six building construction categories established by Insurance Services Office, Inc. (ISO), in its Commercial Lines Manual (CLM) for purposes of developing rates for insuring commercial property, based on susceptibility to damage by fire.

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fire resistive construction (ISO)

Fire resistive construction is one of six building construction categories established by Insurance Services Office, Inc. (ISO), in its Commercial Lines Manual (CLM) for purposes of developing rates for insuring commercial property, based on susceptibility to damage by fire.

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The CLM description of fire resistive construction, followed by the associated ISO construction code, is exterior walls, floors, and roof of masonry or fire-resistive materials with a fire resistance rating of at least 2 hours (Construction Code 6). The construction code indicates the ranking of this building construction category within the six categories, with 1 as the least fire-resistive and 6 as the most fire-resistive.

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