When prewire has to happen
Low-voltage rough-in goes in after framing and electrical rough-in, before insulation and drywall. On a typical Miami custom home that window is two to four weeks long. Miss it and every cable afterward is a fishing job, a soffit, or a wireless compromise.
The design work happens earlier. Rack room location, conduit paths, lighting panel locations and keypad boxes should be on the permit set. That is when we like to join a project, and when the electrician needs our load schedule for panelized lighting.
Room-by-room checklist
Run everything to the rack, home-run, no daisy chains. Use Cat6A for data, 16/4 or 16/2 for speakers, 18/2 or 22/4 for keypads and shades per the manufacturer, and RG6 only where a specific device needs it.
| Location | Run this | Why |
|---|---|---|
| Every TV location | 2× Cat6A, 1× conduit (1 inch) to the rack or attic | AV over IP, future HDMI paths, no wall openings later |
| Every access point location (ceiling) | 1× Cat6A | Wired UniFi access points; never rely on mesh |
| Every camera position | 1× Cat6A (outdoor-rated where exposed) | PoE power and data; sealed penetrations |
| Front door, gate, service entrances | 1× Cat6A + 1× 18/2 to the operator | Video intercom, strike, gate control |
| Every keypad location | Keypad cable per lighting system; a single-gang box | Panelized lighting keypads; decided with the designer |
| Every lighting circuit | Home-run to the lighting panel location | Control4 panelized lighting; coordinated with the electrician |
| Every window with a possible shade | Shade cable + power per manufacturer; pocket or bracket detail | Wired shades that never need a battery |
| Every audio zone (indoor and outdoor) | 16/4 speaker wire to speaker locations, 1× Cat6A for a keypad or touchscreen | Architectural audio, volume control |
| Primary suite, kitchen, great room, office | +1 Cat6A spare and a touchscreen box | Wall touchscreens, desks, future devices |
| Thermostat and HVAC zones | 1× Cat6A + thermostat cable | Climate integration |
| Pool equipment, dock, gate, roof | 1× 1.25 inch conduit each + 1× Cat6A | Pool controller, dock cameras and audio, gate, future antennas |
| Guest house or cabana | Buried conduit with single-mode fiber and Cat6A | A wired network across the lot |
The rack room
Every run terminates here, so treat it like a small mechanical room rather than a closet. The minimum spec we ask builders for:
- A dedicated space at least 4 by 6 feet, or a wall section for a wall-mount rack in smaller homes, away from the laundry and the garage's heat.
- Conditioned air or a dedicated exhaust. Equipment in Miami without cooling fails early.
- Two dedicated 20-amp circuits on the generator side of the transfer switch, plus a grounding point.
- A 3/4 inch plywood backboard on one wall for the lighting panels and the service entrance for internet.
- Conduit from the rack to the attic, to the exterior demarcation point and to the roof.
- Lighting, a door that locks, and no water lines running through it.
Conduit: the cheapest insurance in the house
Cable covers what you know you want. Conduit covers what you will want in ten years. Empty 1 inch and 1.25 inch conduit costs very little at framing and makes the next upgrade a pull rather than a construction project. We run it to every TV, the roof, the gate, the dock, the pool equipment and between floors, and we leave a pull string in each.
Coordinating with the electrician
Panelized lighting is where low voltage and line voltage meet. The electrician wires every controlled circuit to the lighting panel location instead of to a wall switch, and the low-voltage keypads take the switches' place. That needs a load schedule, agreed panel locations and a clear division of scope before rough-in. We produce the load schedule from the lighting design and walk it with the electrician on site.
Shades and motorized devices need power at the window or in the pocket. Intercoms and strikes need low-voltage power at the door. All of it goes on the same drawing so nothing is discovered after drywall.
Testing and documentation before insulation
Every cable is tested and certified before the walls close, labeled at both ends with a scheme that matches the drawings, and photographed in place. The owner receives an as-built cable map at handoff. This is not extra; it is the only proof the prewire was done and the only way the next technician, or we in ten years, know what is in the walls.
Mistakes we see on other people's prewires
- Coax everywhere, Cat6A nowhere. Modern video is over IP.
- One access point location for a 6,000 square foot concrete house.
- No conduit, so the first upgrade opens the great room ceiling.
- Keypad boxes placed by the electrician without the designer, then moved after paint.
- Speaker wire to the rooms but not to the terrace, pool or dock, where Miami homes actually live.
- Rack in a hot garage closet with one outlet.
- Cables unlabeled, untested, and stuffed into a box before drywall.
Questions people ask about this
How much does prewire cost on a new home?
For a 4,000 to 8,000 square foot home, a complete low-voltage prewire including conduit, rack room preparation, testing and documentation typically runs from the mid four figures to the low five figures. It is the cheapest phase of the project and the one with the longest payoff.
Do we have to decide every system before prewire?
No. The point of prewire is to keep options open. Run cable and conduit to every plausible location, then decide on shades, audio and cameras after move-in without opening walls.
Can our electrician do the low-voltage prewire?
Some can pull cable, but few design it, certify it, coordinate panelized lighting and document it. Low voltage is its own trade for a reason. If your electrician pulls it, insist on a drawing, certification results and labels.
What about fiber?
Single-mode fiber belongs between buildings, between floors on large homes, and from the demarcation point to the rack. It future-proofs bandwidth for decades and costs little at framing.
Serving Golden Beach, Miami Beach, Coral Gables and across South Florida.