Photometric Plan

A photometric lighting plan is the fastest way to verify your lighting design before you purchase fixtures or schedule installation. Our lighting designers model your space and recommend fixture layout to confirm key outcomes like target light levels (foot-candles/lux), uniformity, and coverage – so you can avoid dark spots, glare issues, and costly change orders.

Best for: warehouses, manufacturing, gyms, retail, parking lots, sports fields, and outdoor yards – any project where performance, safety, and budget matter.

What You Will Receive With a Photometric Lighting Plan

• Fixture layout showing locations, mounting heights, and aiming (when applicable)
• Foot-candle or lux calculations with average, minimum, maximum, and uniformity ratios
• Calculation grid visual (color/numbered point-by-point readings)
• Fixture schedule with model, optic/beam, lumen package, wattage, CCT, voltage, and controls
• Printable PDF report suitable for internal approvals and many rebate documentation needs

Important: A photometric plan is a design and planning tool. Final electrical design, structural/pole loading, and code compliance must be verified by licensed professionals and the local government authority.

What We Need From You to Build an Accurate Plan

• Basic dimensions (length/width, or a sketch/CAD/PDF/site plan)
• Mounting details (ceiling height, pole height, arm length, or mounting location)
• Existing conditions (current fixture type, quantity, wattage, spacing-optional but helpful)
• Project goals (target brightness, uniformity expectations, and any problem areas)
• Preferences (CCT, control strategy, glare/backlight limits, curfew rules)

Technical Lighting Plan Terms You Should Know

One of the hardest parts of upgrading lighting is predicting performance before installation. A photometric lighting plan solves that problem by using professional lighting software to model your space and simulate fixture placement, mounting height, optics, and aiming (when needed).

Plans can be built from CAD files, PDFs, sketches, or scaled aerial/site layouts for outdoor areas. Once fixtures are placed, the software calculates light levels across a defined calculation area, including average/min/max values and uniformity ratios, then produces a printable PDF report.

Lighting Terms

Lumen (lm): Total light output produced by a lamp or fixture. Lumens help compare output, but they don’t tell you how light lands on the ground without a layout and optics.

Foot-candle (fc): Light level on a surface. 1 foot-candle equals 1 lumen per square foot. Most U.S. lighting plans use foot-candles.

Lux (lx): Metric light level. 1 lux equals 1 lumen per square meter. (1 fc ≈ 10.76 lux.)

Uniformity ratio: A measurement of how evenly light is distributed (commonly expressed as Avg/Min or Max/Min). Better uniformity helps reduce harsh bright spots and dark areas.

Photometric study report: A multi-page PDF summarizing the layout, calculation grids, statistics, and fixture schedule. Many projects use this for internal approval and as supporting documentation for rebates.

IES recommendations: The Illuminating Engineering Society publishes lighting guidance for many applications. Your plan can be designed to target recommended light levels and better uniformity depending on the space and use.

Beam angle / optic distribution: The shape of light leaving the fixture (e.g., narrow, wide, Type II/III/V). Optics strongly affect uniformity, spill light, glare, and spacing.

Ambient vs accent lighting: Ambient is the general “base” light level for a space. Accent lighting highlights focal areas (retail displays, architectural features, signage, etc.).

How to Read a Photometric Plan?

A photometric lighting plan is only useful if you understand how to interpret the data it presents. Each plan displays calculated light levels, uniformity ratios, and fixture placement used to evaluate how well a lighting layout performs within a space. If this is your first LED Lighting Supply photometric plan, the figures and statistics may appear complex at first, but the structure is consistent and straightforward. The example basketball gymnasium plan shown illustrates the four core components found in every photometric lighting plan.

1. Foot Candle Measurements

A foot-candle represents the amount of light that reaches a surface area, and it’s measured in lumens per square foot. In the above plan, you will see that there are several reading points within the lighting plan. These represent the foot-candle readings for each specific point. The average rating and calculation zone’s statistics are used to assess lighting uniformity, helping to determine how the brightest point differs from the least bright point, which is important for visual comfort and compliance. And if you’d rather look at the layout in meters, the software can also calculate lux instead of foot-candles.

2. The Fixtures

The light fixtures, arguably the most important element in a photometric lighting plan, are represented by red dots. In outdoor environments such as parking lots, it is crucial to properly place light poles and use listed fixtures to ensure optimal lighting coverage, safety, and compliance with regulations. The dots indicate the optimal locations for the light fixtures to achieve the best lighting coverage. Fixtures can be swapped out, and plans recalculated to find ideal lighting for specific environments and areas, including parking lot applications and other large outdoor parking lots.

3. The Schedule

This is an extremely important part of a lighting plan that is often overlooked. The schedule is found at the bottom left of your lighting plan, and it goes into further detail about the types of fixtures recommended in the lighting plan. The schedule helps you select the right fixtures by considering factors such as shape, size, and beam angle, and ensures that the lighting solutions provided are tailored to meet the specific needs of your project.

4. The Calculation

This is where some of the most valuable information in the lighting plan is found. This section is found on the right of the schedule and identifies the light levels and distribution ratios of the fixtures outlined in the schedule. It provides some useful information about the foot candle measurements in the plan, including the average, maximum, and minimum. These numbers are often used to ensure that projects are in accordance with building codes.

Out of these numbers, the average is the most significant. This is the ideal or “target” foot-candle reading for the entire project. We can then calculate an Average/Minimum foot-candle reading, which shows us how much the dimmest spot differs from the average.

The Max/Min ratio is also important, as it shows the overall lighting distribution for the space. Building codes are made so that buildings have an even distribution, which helps with visual comfort and safety.

Photometric analysis using these ratios helps identify dark spots and ensures uniform lighting, which enhances visual comfort and prevents areas of insufficient illumination.

Lighting Plan Considerations

What a Photometric Plan Can (and Can’t) Guarantee

• Photometric plans predict light levels based on fixture photometric files, mounting assumptions, and the modeled environment.
• Real-world results can vary due to installation differences (aiming, mounting height), site obstructions (trees, canopies), surface reflectance, voltage conditions, and maintenance factors.
• Outdoor projects may also require pole loading/wind calculations and site-specific code review by qualified professionals.

Inadequate Light Levels or Spotty Distribution

Bad distribution and poor lighting levels are a major issue in the lighting industry. Many facility managers who are looking to convert to LED lighting end up buying products online without going through a proper analysis. They make assumptions about what should work in their space, and encounter problems once they have bought and installed the new lighting. We end up hearing the following complaints often:

• It’s too bright.
• It’s not bright enough.
• The light is not uniform.
• The light is too bright beneath the fixture.

Consulting lighting specialists is essential to ensure proper lighting levels and that all areas are well-lit, which helps prevent these common issues. This is why we always suggest a photometric lighting plan. Otherwise, there is no sure way to know what your outcome will be.

Even though some suppliers will suggest that many fixtures aren’t all that different from each other, we know that couldn’t be farther from the truth. The only way to accurately predict how your lights will look is to have an in-depth understanding of how light behaves in large spaces. But unless you are a lighting engineer, this information is out of your wheelhouse.

And that’s where the photometric lighting plan comes in. A photometric lighting plan takes everything into account and does the math for you so that you can make an informed lighting purchase, whether or not you’re a lighting engineer. The issue with buying lighting fixtures online is that you can’t be 100% sure of what you are buying.

A lot of the time, manufacturers will sell old inventory with outdated features and old chipsets. It may seem like a bargain, but you’ll quickly realize that you’ve made a huge mistake.

Understanding Your Current Light Levels

You can’t understand where you’re going if you don’t understand where you’ve been. Alright, that’s not exactly how the saying goes, but it does still apply here. To understand light levels, let’s introduce the concept of foot-candles and lux. They measure the same concept (light on a surface), but in different units.

You can take light readings using a handheld light meter or an app on your smartphone. A free light meter app gives some reliable basic readings, but if you have a complex light environment or want to be completely sure, we recommend investing in a light meter.

For example, you may have a production facility and are looking to upgrade to LED Shop Lights. A good process would be to install a light meter app on your phone and use it to take several readings around your facility. Go under a light, go between lights, go into the center of the space, go to the edge, and take readings. These measurements can be analyzed by calculating the surface and calculation zone, and are often expressed per square meter to ensure accurate assessment of illumination levels and compliance with lighting standards.

From this, you will get a good idea of how your current lighting is performing and your current light levels. But you can also use this method to determine things like:

• Are my light levels OK, too bright, or too dim?
• Are my light levels pretty uniform and evenly distributed?
• Would I like to improve the light levels, or are things OK?

Frequently Asked Questions

What is a Photometric Plan?

A Photometric Lighting Plan is a digital software report that shows a proposed LED lighting solution placed within an indoor or outdoor area. A photometric lighting study is conducted to simulate and analyze light distribution and illumination levels, allowing you to view the lighting level before work begins on a job site.

Photometric software is used to create a detailed photometric layout, capable of importing layouts, CAD diagrams, and even scaled Google Maps of outdoor areas, particularly interesting when creating lighting plans for commercial spaces, industrial facilities, and outdoor sports facilities.

The software can place the fixtures inside the plan at specific locations and heights, and they can be oriented and aimed. Photometric plan designers interpret photometric data to ensure optimal lighting for both indoor and outdoor spaces, analyzing how light reaches different areas and defining calculation zones for precise analysis. The lighting plan calculates foot-candle light levels, shows how balanced the light is, and provides a comprehensive, printable PDF report.

A Photometric lighting plan isn’t just a type of lighting or a design style. A photometric lighting plan is the study of how light emanates from a fixture into the environment. Our designers translate the technical details into clear recommendations you can purchase and install with confidence.

What is Photometric Analysis?

A photometric lighting plan analysis helps understand how the light from the fixture surrounds the area of coverage. Photometric studies generate detailed photometric reports that summarize key data points, such as average fc and the least bright point in the space, providing essential information for evaluating lighting uniformity and effectiveness. It’s a popular hack used by lighting designers to visualize what the space will look like after fixtures have been installed.

What is a Lighting Layout Calculator?

A lighting layout calculator is another way of saying “Lighting Plan”. Some sites provide some basic lighting calculators, which are good tools for basic budgetary calculations based on light levels needed when you provide some basic data about the light you might use. It is NOT a replacement for a lighting plan.

We would never use an LED lighting layout calculator in place of a lighting plan. Other similar related terms – LED light spacing calculator and free lighting layout tool. A professional lighting designer can help ensure the selection of the right fixtures by considering factors like shape, size, and beam angle, which leads to optimal lighting distribution, greater energy savings, and reduced energy consumption.

Who Is Eligible for Free Photometric Lighting Plans?

We provide complimentary photometric plans for customers who are evaluating and intend to purchase fixtures from LED Lighting Supply. Plans are built around specific fixture models, optics, lumen packages, mounting heights, and controls. Changing the fixture usually changes the results.

• Plans are not offered for projects using fixtures we do not sell.
• We do not provide plans solely to satisfy third-party bid/spec requirements when fixtures are not being sourced through us.
• If you only need a stand-alone plan with no purchasing intent, we can refer you to independent lighting design services.

When Do I Need a Photometric Plan (and What Will It Tell Me)?

We recommend a photometric plan before you buy fixtures anytime your project involves large spaces, high mounting heights, outdoor areas, uniformity requirements, or concerns about glare and dark spots.

Your plan will show predicted average/min/max light levels, uniformity ratios, and a recommended fixture layout and schedule-so you can choose fixture quantity, optics, mounting, and controls with confidence.

How Do You Create a Photometric Plan?

We create lighting plans using highly specialized lighting design software called AGI32 by Lighting Analysts. Photometric software like AGI32 is used to create lighting layouts and visualize the desired lighting effect before installation, allowing designers to optimize the ambiance and functionality of the space.

This program allows us to model spaces, add lights, and calculate the light levels and light balance across the plan. We can easily add/remove and swap/switch fixtures within the plan until the correct light levels and balance are achieved.

How Can I Get A Photometric Lighting Plan?

There are many consultants whom you can pay to run a lighting plan. Our lighting specialists conduct a photometric study to ensure the best results, analyzing your site and lighting needs to create an optimal design. But, using our fixtures, we can create for you a commercial lighting, sports lighting, or industrial lighting design plan.

How Much Does a Photometric Plan Cost?

That depends on who develops the plan. They can cost between $500 and $2000 if you use a specialized lighting design company. Some of our competitors charge you for the plan and then credit you back the cost when you purchase. Our deliverables include a detailed photometric study report and a photometric report summarizing the analysis.

The photometric study report is a comprehensive document, typically 5 to 20 pages, containing graphs, charts, and analysis that follow IES guidelines. The photometric report summarizes lighting analysis results, including light levels, uniformity, and compliance with standards, helping verify lighting design effectiveness and guide luminaire selection. We provide plans for free, with a few exceptions.

We do not provide plans to individuals and companies only looking to have a plan done and with no intention of ever purchasing. Our services are meant for customers who intend to purchase but want to make sure our lights will meet their needs. And, we do not provide plans for lights that we do not sell.

We also do not provide lighting plans for engineers and architects who just need a lighting plan to satisfy their requirements for their customers.

How Do You Calculate Lumens for a Photometric Site Plan?

You should note that 1 lumen per square foot is the same as a 1-foot candle. So, when you read a lighting plan, and see the average foot candles is, for example, 40, that’s the same as saying 40 lumens per square foot.

View Our Lighting Plans By Category

• Commercial Lighting Plans
• Industrial Lighting Plans
• Sports Lighting Plans