Cabling
Firestopping
Sealing cable penetrations through rated walls and floors with tested assemblies so the barrier's fire rating is restored.
Every cable through a rated wall is a hole in a fire barrier. Firestopping restores the rating with an approved sleeve, putty, or intumescent product matched to the assembly and the fill percentage. It is inspected, documented, and non-negotiable in commercial work.
It is also the most common defect we find in buildings that were cabled by whoever was cheapest — open sleeves stuffed with cable and nothing else. Remediation is cheap per penetration and awkward at scale, so it belongs in the scope from day one.
Related terms
- Plenum-Rated Cable
- Cable with a fire-resistant, low-smoke jacket required by code in air-handling plenum spaces — typically the void above a suspended ceiling used for return air.
- Conduit Fill
- The code limit on how much of a conduit's cross-section may be occupied by cable, set so cables can be pulled without damage and can dissipate heat.
- IDF / MDF
- The hierarchy of network rooms in a building: the MDF is the main room where service enters and the core lives; IDFs are floor or zone closets that aggregate nearby horizontal runs back to it.
More Cabling terms
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