Why this page exists
Network cabling for new construction is shaped by how the space is used, not just by the service itself. New construction bring their own operating constraints, and this page pairs what network cabling actually involves with what that environment changes about it.
Network cabling is the permanent copper and fiber pathway between a building's equipment room and every device location. Done properly it is a structured system — horizontal runs from a patch panel out to labeled outlets, each one under the 90-metre permanent-link limit, each one tested and documented. Done casually it is a bundle of unlabeled patch cords stapled to a joist, and every future change costs someone an afternoon of tracing.
One window, and it does not reopen
Low-voltage rough-in happens in a specific slot: after framing and electrical, before insulation and drywall. Inside that window, running a cable anywhere is straightforward. Once drywall goes up, the same cable costs many times more and sometimes cannot be run at all.
The asymmetry is the whole story of new-construction low voltage. Decisions made cheaply during rough-in become expensive or impossible afterwards, which is why the pre-rough-in planning conversation is worth more than any equipment choice made later.
- Rough-in window sits between electrical and drywall
- Upstream delays compress the window without extending the deadline
- Post-drywall changes cost many times more, if they are possible at all
- Finish work happens months later, after paint and ceilings
What network cabling usually involves
Most cabling complaints are not really about speed. They are about traceability and change cost. When nobody can tell which jack feeds which port, a five-minute move becomes a two-hour investigation, and the temptation is to run one more cable rather than fix the underlying mess.
The second cluster of problems is physical: runs that exceed distance limits, cable that has been kinked or over-tensioned during the pull, terminations that violate the pair twist, and shared pathways with electrical conduit that inject noise the switch then has to correct for.
- Unlabeled outlets and patch panels that make every move-add-change expensive
- Runs pushed past the 90-metre permanent-link limit, so the link negotiates down or drops
- Untwisted pairs at the termination point degrading crosstalk performance
- Cable draped on ceiling grid or tie-wrapped to sprinkler pipe rather than supported properly
- No spare capacity, so every new device triggers a new pull
What to rough in even without a final design
Full system design is often not finished when the rough-in window arrives. That is normal, and it is not a reason to skip the pathway. Running conduit or sleeves to likely positions preserves the option cheaply even when the eventual equipment is undecided.
For a commercial building, the reliable rough-in set is: cable to every likely device outlet, ceiling positions for access points spaced for the intended coverage, camera positions at entries and approaches, door positions with cable to the controller location, and pathway to any likely display or AV position. Plus, in every case, a properly located equipment room.
The equipment room deserves particular emphasis because it is the most commonly under-provisioned item. It has to hold the network rack, camera recorder, access-control panel, and any AV equipment, with dedicated power, ventilation, and clearance to work. Sizing it from the network alone is a decision that gets discovered eighteen months later.
- Sleeves and conduit to likely positions even before final design
- Ceiling access-point positions spaced for the intended coverage
- Camera positions at entries, approaches, and service areas
- Cable from every controlled door to the controller position
- Equipment room with dedicated power, ventilation, and working clearance
Distance, pathway, and pair-twist decisions that set the outcome
The governing number is the 90-metre permanent link: the fixed cable from patch panel to outlet. Adding patch cords at both ends brings the total channel to 100 metres. That budget disappears faster than people expect once the cable goes up into the ceiling, across the building, down a wall, and back. A run that measures 70 metres on a floor plan can easily land at 95 metres in reality.
- 90 m permanent link, 100 m total channel including patch cords
- Continuous cable support rather than ceiling-tile or pipe bearing
- Separation from parallel electrical runs; cross at right angles where unavoidable
- Bend radius respected at corners, in the rack, and behind the outlet
- Plenum-rated jacket where the pathway shares an air-handling space
Frequently asked questions
What changes about network cabling in new construction?
The operating environment does. New construction bring specific constraints — how the space is used, when work can happen, and what has to keep running — and those shape the network cabling plan as much as the service's own technical requirements.
How long can a single network cable run be?
The fixed cable between patch panel and outlet is limited to 90 metres, with patch cords at each end bringing the total channel to 100 metres. Beyond that, the answer is not a longer cable — it is either an intermediate equipment location or a fiber link to a secondary switch.
What has to be decided before rough-in?
Device locations, the equipment room position, and the pathway plan. Equipment selection can wait — you can run cable to a position without knowing which camera or access point will go there. What cannot wait is the decision about where things go, because that is what determines where cable is pulled while the walls are open.
