INSIGHTS
Technical guidance for photometric permitting.
A working library for commercial lighting permits, organized by what you need to answer: what a photometric plan is, the requirements reviewers check, the codes that govern them, and how to read the data.
Mar 07, 2026
What Is a Photometric Plan? Complete Guide (2026)
A photometric plan maps light distribution across a site with foot-candle grids, fixture schedules, and compliance data. Learn what's included, what it costs, and when you need one.
Read guidePhotometric Plans
What the deliverable is, what it costs, and what to expect from the process.
Jun 08, 2026
Photometric Plan vs. Study vs. Analysis vs. Report: What's the Difference?
Related but not the same: the analysis is the calculation, the study is the simulation, the plan is the permit deliverable, and a fixture "report" is something else. Here's how to tell which one your jurisdiction wants.
ReadMar 10, 2026
How Much Does a Photometric Plan Cost? 2026 Pricing Guide
Photometric plans typically cost $300-$2,500 for commercial projects. See what drives pricing, what's included, and when "free" plans fall short.
ReadMar 10, 2026
Free Photometric Plans vs. Professional Plans: What's the Real Difference?
Free manufacturer photometric plans sell fixtures. Professional plans serve your project. Here's how to decide which one your project actually needs.
ReadFeb 27, 2026
What to Expect When You Order a Photometric Plan: Timeline, Process & Deliverables
Ordering a photometric plan takes 3–7 business days. Learn the four stages, what you provide, what you receive, and how the plan review process works.
ReadRequirements & Foot-Candles
The illumination levels and uniformity ratios plan reviewers actually check.
Jun 08, 2026
Foot-Candle Requirements by Property Type
How many foot-candles does your property need? IES-based maintained ranges for parking lots, gas-station canopies, dealerships, warehouses, retail, and self-storage — and why they're floors, not targets.
ReadMar 06, 2026
Parking Lot Photometric Requirements — What Plan Reviewers Check
Illumination values, documentation details, property-line checks, and IES RP-8 compliance that plan reviewers look for in parking lot photometric submittals.
ReadMar 10, 2026
IES RP-20 Explained: Parking Lot & Garage Lighting Standards
IES RP-20 sets the foot-candle minimums and uniformity ratios for parking lots and garages — minimums starting at 0.2–0.5 fc, with max-to-min uniformity up to 20:1. See the recommended levels and how plan reviewers apply them.
ReadFeb 28, 2026
Warehouse Lighting Design: Foot-Candle Requirements, Layout Tips & Common Mistakes
Warehouse foot-candle requirements range from 5 fc for storage to 50+ fc for inspection. Learn IES levels, layout strategies, and costly design mistakes.
ReadCodes, Permits & Compliance
Title 24, dark-sky ordinances, light trespass, and why submittals get rejected.
Jun 08, 2026
Do You Need a Lighting Permit? What Compliance Requires and What to Submit
If your permit touches exterior lighting, you almost certainly need a photometric plan. Here's what "lighting compliance" covers, what to submit, and how to avoid a plan-check rejection.
ReadMar 04, 2026
Why Photometric Plans Get Rejected at Plan Check
The most common reasons lighting submittals fail plan review - missing calculations, code gaps, and documentation errors - and how a permit-ready package avoids them.
ReadMar 10, 2026
California Title 24 Lighting Requirements: What You Need for Your Photometric Plan
Title 24 Part 6 sets strict outdoor lighting power and control requirements. Learn what your photometric plan needs for California permit compliance.
ReadMar 10, 2026
Dark Sky Ordinances Explained: What They Mean for Your Lighting Project
Dark sky ordinances regulate fixture shielding, color temperature, and light trespass. Learn what they require and how they affect your photometric plan.
ReadFeb 26, 2026
Light Trespass Explained: How to Prevent Neighbor Complaints and Code Violations
Light trespass is light crossing your property line where it's not wanted. Learn the code limits, common causes, and how to fix or prevent violations.
ReadReading Plans & IES Data
How to read a plan, what IES files contain, and the software behind the numbers.
Mar 02, 2026
How to Read a Photometric Plan — A Plain-Language Guide
Understand calculation grids, contour lines, fixture schedules, property-line checks, BUG ratings, and the code notes plan reviewers care about.
ReadFeb 25, 2026
Understanding IES Files: What They Are, Why They Matter, and How to Get Them
An IES file contains a luminaire's measured light distribution data. Learn what's inside, why it matters for your photometric plan, and where to download them.
ReadMar 01, 2026
DIALux EVO vs. AGi32: Which Software Produces Better Photometric Plans?
AGi32 is the US standard for exterior permit-ready photometric plans. DIALux EVO is free and excels at interior visualization. Here's how they actually compare.
ReadJun 08, 2026
Free Photometric Software & DIY Tools (and When to Hire Instead)
The free and low-cost photometric tools that exist, what they can and can't do, and the point where a permit-grade plan needs verified IES files and a reviewer-ready format.
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