Installing a smart light switch involves turning off the circuit breaker, removing the old switch, connecting the new smart switch to the existing wiring, and configuring it through a smartphone app. It sounds simple, and for a single-pole switch in a newer home with a neutral wire present, it often is a manageable DIY project for someone comfortable with basic electrical work. That said, three-way switches, older wiring without a neutral, aluminum wiring, or any uncertainty about what you’re looking at inside the box are all reasons to bring in a licensed electrician.

Before You Buy: Check for a Neutral Wire

Most smart switches require a neutral wire (typically white) in the switch box to complete the circuit for the switch’s own low-level electronics. Many Denver-area homes built before the 1980s were wired with “switch loops” — a method that doesn’t bring a neutral to the switch box. If you open your existing switch and find only two wires (both insulated, no bare copper ground), you may not have a neutral. Some smart switch brands offer no-neutral models, but they’re more limited in compatibility. Check your wiring before purchasing any device.

Step-by-Step for a Standard Single-Pole Replacement

Here’s the general process for a straightforward single-pole installation:

  • Turn off the breaker for the circuit at your panel and verify power is off with a non-contact voltage tester — never work on a live circuit
  • Remove the switch plate and existing switch, taking a photo of how the wires are connected before you disconnect anything
  • Identify your wires: typically a black (hot), white (neutral), and bare copper or green (ground)
  • Connect wires to the smart switch per the manufacturer’s diagram — hot to hot, neutral to neutral, ground to ground; most use push-in or screw terminals
  • Tuck wires carefully back into the box without pinching insulation, then secure the switch and plate
  • Restore power and follow the app pairing process — most switches use Bluetooth or Wi-Fi for initial setup

Three-Way Switches Are More Complex

If you have two switches controlling one fixture — common on staircases and in hallways — you have a three-way circuit. Smart three-way setups vary by brand: some require a smart switch at one location and a compatible “accessory” (dumb) switch at the other; others require smart switches at both ends. The traveler wires that connect the two boxes add complexity. If you’re not confident reading a three-way wiring diagram, this is a job to hand off to an electrician.

Colorado Code and Permit Considerations

In Colorado, replacing a like-for-like switch — same location, same circuit — generally doesn’t require a permit. But if you’re adding a new switch, moving a switch, or making any changes to the circuit itself, a permit and inspection are typically required under state and local electrical codes. Denver and most Front Range municipalities follow the NEC with amendments. When in doubt, call your local building department or ask a licensed electrician — doing unpermitted electrical work can affect your homeowner’s insurance coverage and complicate a future home sale.

When to Call a Pro Instead

Beyond three-way complexity and missing neutrals, call an electrician if you discover aluminum wiring (silver-colored conductors common in some 1960s–70s homes), a box that’s too shallow to fit a deeper smart switch, or any signs of prior DIY wiring that doesn’t look right. What looks like a simple swap can hide a wiring issue that’s a fire risk.

Done’s electricians handle smart switch and dimmer installations throughout the Denver metro — including tricky three-way setups and older homes without neutrals. Learn more on our outlets and switches page or explore full smart home integration services. We’re also happy to pair a switch install with a broader lighting upgrade if you’re ready to modernize more of your home.