How to Wire Security Cameras in an Existing Building (Without Tearing Walls Apart)

Running cable in a new construction building is straightforward — open walls, accessible ceilings, no tenants to work around. Running cable in an existing, occupied building is an entirely different discipline. Here’s how we approach it for security camera installations across Chicago.

Why Wired Cameras Are Still the Standard

Before discussing cabling methods, let’s address the obvious question: why not just use wireless cameras?

Wireless cameras have their place — temporary deployments, locations where running cable is physically impossible, and quick additions to existing systems. But for permanent commercial installations, wired cameras (using PoE — Power over Ethernet) remain the professional standard because:

• Reliability: No signal interference, no bandwidth competition with Wi-Fi devices, no connection drops
• Power: PoE delivers power and data on one cable — no separate power supply or outlet needed at each camera
• Bandwidth: Wired connections handle 4K streams without compression compromises
• Security: Harder to jam or intercept than wireless signals
• Longevity: Cat6 cable lasts 15-25 years with zero maintenance

Cable Types and When to Use Each

Cat6 (Standard for New Runs)

Cat6 is the standard cable for IP security cameras. It supports PoE power delivery up to 100 meters (328 feet) and provides more than enough bandwidth for any current camera.

Always use Cat6 for new runs — the cost difference from Cat5e is negligible, and Cat6 provides better performance margin and future-proofing.

Cat6A (For Long Runs and High-Power Cameras)

Cat6A is shielded and rated for longer distances at full bandwidth. Use Cat6A when:

• Cable runs exceed 200 feet
• Cameras require PoE++ (60W+) — PTZ cameras with heaters
• Runs pass through areas with heavy electromagnetic interference (near elevator motors, heavy machinery)

Existing Coaxial Cable

Many older Chicago buildings have coaxial cable from legacy analog camera systems. If the coax is in good condition, you can potentially use Ethernet-over-coax (EoC) adapters to carry IP camera signals without pulling new cable. This saves significant installation cost in buildings where pulling new cable is extremely difficult.

The tradeoff: EoC adapters typically limit bandwidth to ~100 Mbps and PoE delivery to ~30W. Adequate for 4MP cameras but may limit 4K or high-power PTZ cameras.

Finding Cable Pathways in Existing Buildings

Drop Ceilings (Best Case)

Commercial buildings with drop ceilings (suspended ceiling tiles) are the easiest to cable. The space above the tiles typically provides clear pathways for running cable from camera locations to the network closet.

Key considerations:

• Fire-rated plenum cable (CMP) is required in the plenum space above drop ceilings in most Chicago buildings
• Avoid laying cable directly on ceiling tiles — use J-hooks or cable tray to support runs
• Keep camera cable away from electrical and fluorescent ballast wiring (minimum 12” separation)
• Plan cable routes to avoid mechanical equipment, sprinkler pipes, and fire dampers

Conduit (Exposed Environments)

In parking garages, warehouses, loading docks, and mechanical areas, exposed cable is vulnerable to damage. All runs in these areas should be in conduit:

• EMT (Electrical Metallic Tubing) — rigid metal conduit, professional appearance, good protection
• ENT (Electrical Nonmetallic Tubing) — flexible “smurf tube,” easier to install around obstacles but less protective
• PVC conduit — for outdoor and underground runs

Conduit adds significant labor cost (roughly doubling the per-camera cabling expense) but is necessary for long-term reliability.

Surface Raceway (Finished Spaces)

When you can’t access ceiling spaces or wall cavities, surface raceway (Wiremold) provides a clean exterior cable pathway along walls and ceilings. It’s painted to match the wall color and provides a professional appearance.

Surface raceway is common in:

• Retail stores with finished ceilings
• Historic buildings where opening walls isn’t permitted
• Residential corridors in condo buildings
• Areas where the building owner doesn’t want visible cable

Core Drilling (Between Floors)

Getting cable from one floor to another in an existing building usually requires core drilling — creating a new penetration through the floor or ceiling. This requires:

• Building owner approval
• Knowledge of structural elements (don’t drill through rebar or post-tension cables)
• Fire-stopping after cable installation (code requirement)
• Sometimes a structural engineer’s assessment in older buildings

Minimizing Disruption in Occupied Buildings

Work Schedule Planning

For Chicago offices and occupied buildings, we schedule cable pulls during off-hours when possible — evenings, weekends, or holidays. Overhead ceiling work generates dust and noise that disrupts normal business operations.

Pre-Installation Preparation

Before the cable crew arrives:

1. Pathway survey — walk every cable route to identify obstacles, access points, and potential issues
2. Pull string — in longer runs, pre-install pull strings in conduit or ceiling pathways
3. Material staging — pre-cut and label cable spools to minimize on-site mess
4. Access coordination — arrange building access, freight elevator scheduling, and parking for the crew

Clean Work Standards

Our cabling team follows clean-work protocols:

• Plastic sheeting under all ceiling work areas
• Ceiling tiles replaced and aligned after cable installation
• All debris removed daily (no “we’ll clean up at the end of the project”)
• Cable supports installed properly (no cable resting on ceiling tiles)
• All penetrations fire-stopped before leaving the floor

Network Closet Setup

All camera cables terminate at a network closet (or IDF — Intermediate Distribution Frame). This is where your PoE switch and NVR live.

Requirements for the network closet:

• Power — dedicated circuit for PoE switch and NVR, connected to UPS
• Cooling — enclosed closets need ventilation or cooling; PoE switches and NVRs generate significant heat
• Physical security — locked door or rack; this room contains all your camera infrastructure
• Patch panel — all camera cables terminate at a labeled patch panel for clean, documented connections
• VLAN-capable switch — managed switch with PoE budget sufficient for all cameras plus growth

When Wireless Makes Sense

Despite our preference for wired cameras, wireless solutions are appropriate in specific situations:

• Temporary coverage during construction or renovation
• Outdoor point-to-point links between buildings where trenching isn’t feasible
• Adding 1-2 cameras to an existing system where running cable would be disproportionately expensive
• Historic landmark buildings where any physical modification requires preservation board approval

For wireless camera links, we use commercial-grade wireless bridges from Ubiquiti — not consumer Wi-Fi cameras. Point-to-point wireless bridges deliver reliable, dedicated bandwidth for camera traffic.

Get a Cabling Assessment

Every building is different. A site walkthrough reveals the cable pathways, obstacles, and opportunities that determine the most efficient approach and accurate cost estimate. Schedule a walkthrough or call (872) 254-5015 — we assess your building’s cabling situation as part of every camera system proposal.