Short answer
DIY is reasonable for simple, like-for-like tasks on existing circuits (e.g., swapping a light fixture, replacing a switch or receptacle, installing a GFCI) if you understand how to work de-energized and test correctly. Hire a licensed electrician for anything involving new circuits, service panel work, aluminum/old wiring, troubleshooting persistent faults, permits, or if you’re unsure about code requirements.
What you can DIY vs. when to call a pro
DIY-friendly (for confident homeowners)
- Replace light fixtures or basic switches/receptacles on the same circuit
- Upgrade a standard receptacle to a GFCI in a bathroom, kitchen, garage, basement, outdoor location
- Install a listed dimmer on a compatible light load
- Replace a standard ceiling light with a ceiling fan only if the box is fan-rated and supported
- Replace faceplates, tighten loose connections, label circuits
Typical time and cost:
- Outlet or switch replacement: 20–45 minutes; parts $2–$6 (standard), $18–$30 (GFCI)
- Light fixture swap: 30–60 minutes; parts vary widely
- Ceiling fan replacement (existing fan-rated box): 60–120 minutes
Hire an electrician for
- New circuits or extending circuits (kitchen appliances, EV chargers, dedicated 20A laundry, 240V tools)
- Any service panel work (adding/replacing breakers, service upgrades, subpanels)
- Aluminum wiring repairs, knob-and-tube issues, or no-ground systems
- Pool/spa/hot tub wiring, outdoor structures, low-volt landscape systems tied to line voltage
- Generator transfer switches/interlocks, whole-house surge protection
- Troubleshooting tripping breakers, flickering lights, warm outlets, buzzing, burning smells
- Work that requires a permit/inspection or you’re selling the home soon
Rough pro costs (varies by region):
- Hourly/minimum: $100–$175/hr, typical minimum $150–$300
- New dedicated 20A circuit: $300–$800
- EV 240V circuit: $400–$1,200
- Service upgrade (100A to 200A): $2,000–$5,000+
Quick decision checklist
- Are you staying on the same circuit with no panel work? DIY-friendly.
- Do you fully understand how to test for power off with a proper tester? If not, hire out.
- Does the job add load, add a circuit, or require fishing cable through walls? Likely pro + permit.
- Is there aluminum wiring, cloth insulation, or two-prong outlets with no ground? Pro.
- Are there signs of damage (scorching, melted insulation, repeated trips, shocks)? Pro immediately.
Step-by-step: Replace a standard receptacle with a GFCI
Tools and materials:
- Non-contact voltage tester and a two-pole tester or multimeter (for verification)
- Receptacle tester with GFCI button
- GFCI receptacle (weather-resistant for outdoors; tamper-resistant indoors)
- Wire stripper/cutter, linesman pliers, screwdriver set (torque screwdriver preferred)
- Pigtail wires (14 AWG for 15A circuits, 12 AWG for 20A), UL-listed wire connectors (lever nuts or wirenuts)
- Label tape or a fine marker
Steps:
1. Turn off the correct breaker and confirm the outlet is dead with both testers. Test the tester on a known live outlet first.
2. Remove the cover plate and receptacle. Keep track of how wires were connected.
3. Identify LINE (incoming power) vs LOAD (downstream). If you’re not protecting downstream outlets, cap the LOAD terminals.
4. Make solid connections: ground (green screw), neutral to silver, hot to brass. Use pigtails if you’re tying multiple wires.
5. Torque terminal screws to the device’s spec and avoid backstab-only holes. Fold wires neatly into the box.
6. Reinstall, restore power, press RESET, then test with the built-in TEST button and a receptacle tester.
7. Apply the included “GFCI protected” and “No equipment ground” labels if applicable.
Time: 20–40 minutes. If the box is shallow or crowded, consider a “deep” old-work box and call a pro if box-fill is exceeded.
Key specs to keep in mind
Breaker to wire size:
- 15A circuit → 14 AWG copper
- 20A circuit → 12 AWG copper
Continuous loads:
- Don’t exceed 80% of the circuit rating for loads expected to run 3+ hours.
Protection locations:
- GFCI: bathrooms, kitchens, garages, basements, outdoors, laundry, within 6 ft of sinks.
- AFCI: most living areas and bedrooms (often at the breaker).
Tools that make DIY safer and cleaner
- Non-contact voltage tester + two-pole voltage tester (verify de-energized)
- Torque screwdriver (meets device torque specs)
- Wire stripper with AWG markings, linesman pliers, needle-nose pliers
- UL-listed lever connectors (e.g., Wago-style) for pigtails
- Stud finder, fish tape or glow rods for cable fishing, headlamp, insulated staples for NM-B
- Fan-rated ceiling brace for fan installs
- Plug-in receptacle tester with GFCI button
Check the ToolStash catalog for these tool types and rated electrical boxes, clamps, and covers.
Safety and best practices
- Always de-energize at the breaker and verify with two methods. Keep one hand away from the box if the panel is open.
- Label circuits as you discover them. Take photos before disconnecting wires.
- Use the device’s back-wire clamp or side terminals, not spring backstabs.
- Bond grounds: all grounds tied together with a pigtail to the device and metal box (with a listed clip or screw).
- Respect box fill. If it’s tight, upgrade the box rather than cramming.
- Follow torque specs printed on devices and breakers to avoid loose, heat-prone connections.
- Maintain cable protection: staples within 8–12 in. of boxes, nail plates where cables pass near studs.
Common mistakes to avoid
- Working live or relying only on a non-contact tester
- Mixing wire sizes on a circuit or putting 14 AWG on a 20A breaker
- Replacing a two-prong receptacle with a three-prong without a ground or GFCI method
- Using the LOAD terminals on a GFCI without understanding downstream implications
- Installing a ceiling fan on a light-rated box
- Overstuffing boxes and skipping pigtails
Call a professional immediately if you notice
- Frequent breaker trips, lights dimming/flickering, buzzing from panel or devices
- Warm or discolored outlets/switches, burning smell, or arcing
- Water intrusion in boxes, corrosion, or rodent-damaged wiring
- Unknown wiring types (aluminum, knob-and-tube) or missing grounds
Permits and inspections: Many jurisdictions allow homeowners to do minor work on their primary residence, but adding circuits or panel work usually requires a permit and inspection. If you’re unsure, a quick call to your building department or hiring a pro can save time and risk.