Introduction

Temporary power is the invisible backbone of many residential remodels, additions, and exterior projects. Get it wrong and you risk delays, failed inspections, tripped breakers, and safety incidents. This guide explains what to choose (generator, temp service, or existing supply), why it matters for productivity and compliance, and how to size, set up, and coordinate with utilities and inspectors. You will learn cost ranges, timelines, NEC Article 590 essentials, and practical tips that reduce risk and downtime on real jobs.

Table of Contents

• Key Takeaways
• Choose The Right Temporary Power Strategy
• Set Up Safe And Compliant Temporary Power
• Size Loads And Circuits Correctly
• Coordinate Utilities, Permits, And Timelines
• Control Costs And Prevent Theft
• Frequently Asked Questions
• Conclusion

Key Takeaways

• According to OSHA, electrocutions account for roughly 7% of construction fatalities; NEC 590 compliance and GFCI protection significantly reduce risk.
• Utilities typically require 2–4 weeks to set a temporary service; planning early avoids idle crews and generator overruns.
• Industry data shows loaded labor often runs $55–$85 per hour per tradesperson; a tripped circuit can waste 30–60 minutes for a 3‑person crew, costing $165–$255.
• CPSC reporting indicates GFCI use has reduced residential electrocutions by over 80% since the 1970s—use GFCI on all 125‑V, 15/20‑A receptacles.
• Temporary service poles usually cost $750–$1,800 installed; small generators rent for $60–$150 per day plus fuel at roughly 0.5–0.8 gal per hour at 50% load.

Choose The Right Temporary Power Strategy

The Problem

Many small jobs jump straight to a generator without considering total duration, load diversity, noise, and fuel logistics. The result: outages, neighbor complaints, and costs that exceed a simple temporary service or safe tie‑in.

The Solution

Use a simple decision framework based on duration, load, and access.

Quick Rules Of Thumb

• Under 7 days and less than 3 kW average: generator.
• More than 2 weeks or frequent 240 V loads (compressor, table saw, heater): temporary service.
• Interior-only with controlled access and clear AHJ policy: temporary feeder from existing panel with GFCI protection.

Real-World Example

A siding contractor planned three weeks of exterior work with paint sprayers, saws, and compressors. They initially priced a 7 kW generator at $95/day plus fuel (estimated $28/day). Switching to a 100 A temp service ($1,200 all‑in) saved about $550 over three weeks and eliminated noise complaints, improving crew productivity by an estimated 8%.

Set Up Safe And Compliant Temporary Power

The Problem

Temporary setups often miss critical NEC Article 590 requirements: missing GFCI, non‑weatherproof devices, poor grounding, and cord tripping hazards. AHJs report first‑time temp power inspection pass rates near 65–75% in many jurisdictions.

The Solution

Follow NEC 590 (2023) and OSHA 1926 Subpart K essentials.

Core Compliance Checklist

• GFCI Protection: GFCI on all 125 V, 15/20 A receptacles (NEC 590.6). Use in‑panel GFCI breakers or GFCI receptacles.
• Weatherproofing: NEMA 3R enclosure for temp panel; in‑use weather covers for outdoor receptacles.
• Grounding and Bonding: Ground rod(s) sized per NEC 250; bond neutral only at service disconnect if a separately derived temporary service.
• Feeder Protection: Sized conductors and overcurrent protection; no undersized cords for continuous loads.
• Wiring Methods: Listed outdoor cords; protect from abrasion and traffic; no splices lying on grade.
• Lighting: Provide adequate task lighting; consider low‑voltage or battery lights in confined spaces.
• Housekeeping: Cord ramps or overhead support in walkways; keep energized components elevated above wet areas.

Materials Bill Of Materials (Typical 100 A Temp Service)

• 100 A NEMA 3R panel with main breaker and 4–8 spaces
• Two 20 A GFCI breakers (receptacle circuits), one 30 A 2‑pole (compressor/heater), spares
• Two 20 A weather‑resistant, tamper‑resistant duplex receptacles in in‑use covers
• 6 AWG copper grounding electrode conductor; 8 ft ground rod(s) with listed clamps
• #2–#4 AWG aluminum SE cable (utility spec dependent), service mast, meter base (per utility)

Real-World Example

On a kitchen gut, the GC failed inspection for missing in‑use covers and inadequate grounding. Correction added $185 in materials and a 2‑day delay. Standardizing a temp power kit (panel, GFCI breakers, in‑use covers, ground rod) raised their first‑pass approvals to 92% across six projects in 2024–2025.

Size Loads And Circuits Correctly

The Problem

Undersized generators or circuits lead to nuisance trips and idle time. With loaded labor at $55–$85/hour per tradesperson, a single 40‑minute outage for a 3‑person crew can cost $110–$170 in lost production.

The Solution

Estimate running and starting loads, then size for 125% of continuous loads plus motor starting surge.

Common Jobsite Loads (Typical Values)

Sizing Steps

1. List concurrent loads (what actually runs together).
2. Add running amps per leg for 120/240 V systems.
3. Apply 125% to continuous loads (three hours or more) such as heaters or lighting.
4. Verify breaker sizing and cord ampacity; avoid daisy‑chaining power strips.

Real-World Example

For a winter bath remodel: compressor (12 A starting 24 A), miter saw (12 A starting 24 A), shop‑vac (10 A), and 5 kW heater (240 V, 21 A). Solution: two 20 A 120 V GFCI circuits separating saw and compressor, plus a dedicated 30 A 240 V circuit for the heater. Result: zero trips over two weeks and steady production.

Coordinate Utilities, Permits, And Timelines

The Problem

Temporary service requires utility coordination and inspections. Utilities commonly need design approval and scheduling, which can take 10–20 business days. Starting the project without this plan creates costly downtime.

The Solution

Front‑load the process during bidding and contract signing.

Typical Timeline (United States, Residential)

1. Day 0–2: Submit temp service request to utility; confirm meter base type and clearances.
2. Day 2–5: Electrician installs service pole/panel to utility spec; schedule AHJ rough/temporary inspection.
3. Day 5–10: AHJ inspection and corrections if needed.
4. Day 10–20: Utility sets meter and energizes.

According to utility service data and contractor reports, 2–4 weeks end‑to‑end is common for temporary services, longer in peak seasons.

Documentation To Prepare

• Site sketch with pole location, clearances from driveways and overhead lines
• Panel schedule with GFCI protection identified
• Grounding detail per NEC 250
• Utility spec sheet for meter base and mast height

Real-World Example

A whole‑home repaint with minor exterior carpentry coordinated temp power during proposal. The GC submitted the utility request within 24 hours of contract signature and passed inspection on first attempt. Power was live by day 9, avoiding approximately 12 crew‑hours of generator downtime and refueling.

Control Costs And Prevent Theft

The Problem

Generators consume fuel and attract theft; open panels and cords invite vandalism and tripping claims. National Equipment Register analyses estimate annual construction theft losses at $400M–$1B, with recovery rates below 25%.

The Solution

Implement a cost control and security checklist.

Cost Controls

• Match strategy to duration to avoid fuel burn: a 7 kW unit at 0.6 gal/h for 8 hours/day costs roughly $29/day at $6/gal equivalent; over three weeks that rivals a temp service.
• Use scheduled circuits: assign heavy loads to dedicated breakers; post a one‑page panel schedule on the door.
• Metering: For shared sites, install a sub‑meter or photograph the meter weekly for accurate cost allocation.

Theft And Tamper Prevention

• Lockable NEMA 3R enclosures; padlock cord reels and generator frames.
• Etch or label equipment; record serials; anchor small generators with security cables.
• Night lighting and motion sensors near power setups; store long cords offsite or in locked boxes.

Real-World Example

A deck builder reduced generator fuel spend by 36% by enforcing an “idle‑off” policy and moving saw cuts to a single power zone near the panel. They also added a $90 security cable and low‑cost camera, eliminating two prior theft incidents in one season.

Frequently Asked Questions

Do I Need GFCI On Temporary Receptacles?

Yes. NEC 590.6 requires GFCI protection for all 125 V, 15 and 20 A receptacles used on the jobsite. Using GFCI breakers or GFCI receptacles with in‑use covers is acceptable. CPSC data shows GFCI use has reduced residential electrocutions by over 80% since the 1970s.

What Size Temporary Service Should I Request?

For most small residential projects, 100 A 120/240 V single‑phase is adequate. If you expect multiple 240 V heaters or heavy equipment, consider 200 A. Build a simple panel schedule and confirm with your electrician and AHJ before ordering.

How Deep Must I Bury Temporary Feeder Cables?

Follow NEC Table 300.5 and local amendments. As a general reference, rigid metal conduit can be shallower than direct‑buried cable, while many residential direct‑buried circuits require around 24 inches of cover. Always confirm with your AHJ and utility specs for temporary installations.

How Long Does Utility Energization Take?

Industry experience indicates 2–4 weeks is typical from request to meter set, depending on inspection timing and utility workload. Start the process as soon as the contract is signed to avoid idle time.

When Is A Generator Better Than A Temporary Service?

Short jobs (under a week), remote sites, or projects with very light loads favor generators. Once duration exceeds two weeks or you need reliable 240 V power, a temporary service often becomes cheaper and more productive.

Conclusion

Planned correctly, temporary power becomes a productivity tool instead of a risk. Choose the right strategy for duration and load, follow NEC 590 basics, size circuits to prevent trips, and coordinate early with utilities. To capture site conditions and line‑item temporary power clearly in your proposals, use Donizo. With Donizo’s voice‑to‑proposal workflow, you can record site distances, expected loads, and photos on the spot, generate a branded PDF, send it with client portal access for e‑signature, and convert accepted proposals to invoices in one click. For teams that need invoicing, payment tracking, templates, and analytics, Donizo’s paid plans streamline the entire acceptance‑to‑payment loop while you keep crews powered and productive.