Project Delivery
Division 27 / 28
Also called: CSI Division 27, CSI Division 28, MasterFormat
The CSI MasterFormat sections covering low-voltage work: Division 27 is communications — cabling, AV, paging — and Division 28 is electronic safety and security, including access control and surveillance.
On construction projects, these numbers determine who is responsible for what and where scope gaps appear. Reading the specification by division is how you find out that conduit is in Division 26 electrical while the cable inside it is Division 27 — and that nobody has been assigned the sleeves between them.
Bidding low-voltage work means reading both divisions plus the electrical division and the drawings together. Most disputes we see on commercial jobs trace to an item each trade assumed belonged to another division.
Related terms
- Scope of Work
- The document defining exactly what is included, excluded, and assumed on a project — deliverables, quantities, responsibilities, and acceptance criteria.
- Submittal
- Documentation — product data, shop drawings, samples — submitted to the architect or engineer for approval before equipment is ordered or installed.
- AHJ
- The local official or agency — building department, fire marshal, electrical inspector — with authority to interpret and enforce code on a given project.
- Rough-In
- The construction phase where pathways, boxes, sleeves, and cable are installed before walls close, ahead of any device or equipment installation.
More Project Delivery terms
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Our engineers will review your drawings or quote and tell you exactly where Division 27 / 28 belongs in the design.
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