What Should You Prewire Before the Drywall Goes Up in a Commercial Building?

Once walls and ceilings are finished, adding low-voltage cabling usually turns into a retrofit problem instead of a straightforward rough-in decision. A commercial building's low-voltage infrastructure — data and network cabling, wired backhaul for wireless access points, cabling and pathways for security cameras and access control, connections for conference-room AV and displays, a planned equipment location, and enough spare conduit and pathway capacity for what comes next — is considerably easier to plan and install while walls and ceilings are still open than afterward. None of it needs to be finalized in exact detail before construction starts, but it needs to be part of the conversation early, because the options narrow considerably once framing, ceilings, and finishes are in place.

This is written for the people actually making that call: general contractors, builders, business owners, and facility or property managers planning new construction, a tenant improvement, a remodel, or an expansion — office, retail, warehouse, agricultural or packing facility, logistics space, or anything in between.

Why Early Planning Matters More Than a Fixed Sequence

Low-voltage planning works best when it starts during building design, not once framing is already up. Telecommunications and low-voltage pathways — device locations, cable routes, equipment-room space, and conduit — need to be coordinated with the architect, electrical, mechanical, and other trades before walls and ceilings close, so conflicts get resolved on paper instead of discovered in the field. Telecom design guidance that follows standard industry practice makes this point directly: infrastructure planning belongs in the preliminary design phase, with the goal of coordinating between disciplines during design rather than making adjustments in the field during construction.

The actual construction sequence varies by project — some low-voltage rough-in happens alongside electrical rough-in, some follows it, and the order depends on the general contractor's schedule and how the trades are coordinated on that specific job. There's no single universal sequence that applies to every project. What doesn't vary is the underlying constraint: once walls, ceilings, and door assemblies are finished, running a new cable or adding a device location becomes a retrofit rather than a rough-in task.

The list below isn't a claim that every project needs every item on it, either. A small retail buildout has a different real scope than a multi-suite office or a packing facility with a detached equipment building. The point of going through it isn't to check every box — it's to make each decision on purpose, while it's still straightforward to change.

Network & Data Cabling

Every device that needs a wired connection — desktop computers, phones, printers, point-of-sale terminals, wireless access points, and cameras — needs a cable run to a central location before that location is behind a finished wall. The specific cable category (Cat6, Cat6A, or fiber for backbone runs) depends on the building's size, expected bandwidth needs, and how far a run has to travel — there's no single "always use this" answer, and a contractor should size the cabling to the actual project rather than defaulting to the highest spec by habit. What matters most at this stage isn't which category gets chosen — it's making sure every location that will eventually need a wired connection actually gets a cable pulled to it, since adding a new run later is generally the harder and more disruptive part, not upgrading the cable category itself.

Wireless Access Points

Wi-Fi access points need a wired connection back to the network (their backhaul), and that means a cable run to wherever the access point will actually be mounted — usually the ceiling. Once the ceiling is finished, adding a new AP location generally means either a surface-mounted cable run or opening the ceiling back up. It's generally easier and less disruptive to run a cable to a few extra candidate locations while the ceiling is still open than to add one after the fact. (How many access points a given space actually needs depends on the building's construction, layout, and device load — we cover that question in more detail here — but the decision at this stage isn't "exactly how many," it's "make sure the ceiling locations that are likely candidates have a cable run to them before they're finished.")

Security Cameras and Access Control

Camera cabling has its own planning requirements that go beyond "point a camera where you want to see something." For a modern PoE (Power over Ethernet) IP-camera system, each camera location needs a network cable run back to a switch, and that switch needs enough PoE capacity, available ports, and uplink bandwidth to carry the cameras being added. An existing network should not automatically be assumed to have the switching, PoE, and uplink capacity a planned multi-camera surveillance system will need — that's worth checking rather than assuming. (Not every camera system is IP/PoE-based, so the specific cabling requirement depends on which system is actually selected — but that selection is exactly the kind of decision worth making before the wall behind the camera is finished.)

Access-control doors have a different, more varied set of requirements depending on the system chosen. Planning typically needs to account for reader wiring at the door, lock wiring and power, door-position contacts, request-to-exit devices, and where the controller for that door (or group of doors) will actually live, along with the pathway connecting all of it back to the controller location. Not every component runs on the same kind of cable, and not every reader is an Ethernet device — the actual wiring architecture depends on the access-control system selected. What matters at this stage isn't nailing down every wire type in advance; it's making sure the door frame, wall, and ceiling aren't finished before someone has confirmed what that door actually needs.

Conference Rooms, AV, and Displays

Conference rooms and any space with a wall-mounted display, video conferencing setup, or presentation system need more than a single power outlet behind the screen. Depending on the system, that can mean a data drop for the display and camera, a separate run for control equipment, and conduit or a cable pathway between the display wall and wherever the AV equipment itself will live (a rack, a credenza, or a dedicated equipment room). Deciding the display location and equipment location together, before the wall behind the display is closed, avoids a surface-mounted cable run being the only option later.

Planning the Equipment Location

Every structured cabling system needs a planned location where cabling terminates and network equipment lives — not necessarily a dedicated room on a small project, but a deliberate decision rather than whatever space happens to be left over. Depending on the size and layout of the building, that might mean a single equipment closet, a proper telecommunications room, or, on a larger or multi-area building, a main distribution location plus one or more secondary telecom rooms extending the network to other parts of the building without long, unmanaged cable runs. In the field, this is commonly referred to as an MDF (Main Distribution Frame) and, where a building needs more than one, IDFs (Intermediate Distribution Frames) — terms worth knowing since a cabling contractor or vendor will likely use them, even though not every project needs the full multi-room version.

Wherever that space ends up — closet, room, or full MDF/IDF setup — its location matters. It affects how far every cable run has to travel (which affects both practicality and, past a certain distance, signal performance), how easy the space is to service later, and whether it has adequate power and ventilation for the equipment that will live there, including room to add equipment later. Picking that location early is worth prioritizing, because every other cable run in the building is measured from it.

Fiber and Inter-Building Connections

If a project includes more than one building — a detached shop, a separate warehouse, a second structure on the same property — getting a reliable connection between them is its own design decision, and it's considerably easier to solve with conduit or fiber while the ground is still open than after landscaping and hardscape are finished. (We've written in more detail about when a wireless bridge is the right call versus running dedicated fiber between buildings.) Even where a wireless bridge is the plan for now, having conduit in the ground as a future option is worth considering while the trenching is already happening for other utilities.

Conduit, Pathways, and Room to Grow

Conduit and cable pathways are generally considerably easier to add during rough-in than afterward. An empty conduit run to a likely future location, or extra capacity in a cable tray or pathway, is a straightforward addition while walls and ceilings are open, and can avoid a real disruption later if the building's needs change — another camera, an additional access point, a future tenant space. This isn't a recommendation to over-build every project; it's a case for treating spare pathway capacity as a real line-item decision during planning rather than something that only gets considered after it's needed and the walls are already closed.

Coordinating With the GC, Electrical, and Other Trades

Low-voltage work doesn't happen in isolation, and a common source of change orders on a commercial project isn't the cabling itself — it's a gap in who was supposed to provide the pathway for it. Responsibility for conduit, sleeves through fire-rated assemblies, cable tray, and other pathway work varies by project: it can sit with the electrical scope, the low-voltage scope, or be split between them, depending on how the project documents and GC contracts are written. There's no single default that applies to every job. What matters is that those responsibilities get assigned explicitly, in writing, before rough-in — not assumed. When that division isn't spelled out, low-voltage work can end up waiting on pathway nobody was actually contracted to install, discovered only once the ceiling is about to close. An above-ceiling coordination meeting with the GC, electrical, HVAC, and low-voltage trades, held before rough-in rather than after a conflict is discovered, is standard practice on projects that avoid this problem.

What Your Low-Voltage Contractor Needs From You

A short, practical list of what makes that conversation productive, whether it happens during design or closer to rough-in:

• Architectural or reflected ceiling plans, so cable routes can be planned around HVAC, plumbing, and structural elements rather than discovered mid-installation
• A general sense of what each space will be used for (offices, conference rooms, retail floor, warehouse racking) — the cabling and pathway needs are different for each
• Whether the project includes more than one building or any outdoor coverage areas
• Whether security cameras, access control, or a specific AV/conference-room system are planned, even if the exact equipment isn't chosen yet
• Any known future-growth plans (an additional suite, a planned expansion) that might justify extra conduit or spare capacity now
• Who is responsible for providing conduit, sleeves, and pathway versus who is responsible for the cabling itself, confirmed in writing rather than assumed

Common Mistakes That Create Retrofit Problems After Drywall

• Assuming a general contractor's electrical scope automatically includes low-voltage pathway, and discovering the gap only once the ceiling is closing
• Picking camera or access-point locations based on where they'll look right, without confirming a cable can actually reach that spot
• Treating the equipment location as leftover space (a closet, a corner) rather than a location chosen for cable-run distance, power, and ventilation
• Assuming an existing or newly-installed office network has the switch and PoE capacity to absorb a planned PoE/IP-camera system added later, without checking
• Skipping spare conduit or pathway capacity to save a small amount up front, then facing a disruptive wall-opening for the next addition

A Pre-Drywall Checklist

• Has every planned network-device location — desks, access points, IP cameras, and displays — had the required cable run planned, and have the wiring and pathway requirements for access-control doors been identified?
• Has the equipment location been chosen based on cable-run distance, power, and ventilation, not just available space?
• If the project includes more than one building, has the connection between them been planned while trenching or conduit work is still possible?
• Is there spare conduit or pathway capacity for realistic future growth?
• Has responsibility for conduit, sleeves, and pathway been explicitly assigned between the electrical and low-voltage trades, in writing?
• Has the low-voltage contractor reviewed the architectural plans with the GC and other trades before rough-in?

Plan the Infrastructure Before the Walls Close

Getting low-voltage infrastructure right isn't really about the cabling itself — it's about which decisions are still straightforward to make and which ones have already turned into a retrofit problem. A conversation with a structured cabling contractor early — during design if possible, before rough-in at the latest — is what keeps those decisions simple instead of turning them into a retrofit later.

If you're planning new construction, a tenant improvement, or an expansion in the Yuma area, WOW Electronics designs and installs structured cabling and business network infrastructure built around how the building will actually be used, and can review plans and coordinate with your GC and other trades before rough-in. Contact WOW Electronics to talk through a project before drywall goes up.