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modified fire resistive construction

Modified 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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modified fire resistive construction

Modified 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 modified fire resistive construction, followed by the associated ISO construction code, is exterior walls, floors, and roof of masonry or fire-resistive material with a fire resistance rating of at least 1 hour but less than 2 hours (Construction Code 5). 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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