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The lighting specification process translates a commercial project’s lighting goals into documented requirements for fixtures, controls, installation, and verification. It connects commercial lighting design with the products contractors purchase and install.

A lighting specification defines the performance, physical characteristics, and acceptance criteria those products must meet. Creating one involves more than choosing fixtures: the team must coordinate architectural details, electrical systems, budget, and availability, and establish how proposed alternatives will be evaluated.

Key Takeaways

Clear specifications give project participants a shared basis for selecting and reviewing products. Use this checklist to keep design requirements, documentation, and purchasing decisions aligned:

    • Define measurable lighting requirements, including illuminance in lux or foot-candles, CCT, and CRI, before fixture selection.
    • Align fixture schedules, written CSI Division 26 specifications, reflected ceiling plans (RCPs), and photometric calculations.
    • Require complete optical and driver data before approving “or equal” submittals.
    • Establish who reviews product changes and verifies factory lead times.
    • Evaluate value engineering against total installed cost, operation, maintenance, and required performance.

Who Specifies Lighting on a Commercial Project?

Architects, electrical engineers, and lighting designers typically develop lighting specifications together, with input from owners, manufacturer representatives, distributors, and contractors. The lead specifier and approval authority depend on the project’s delivery method, contracts, and scope.

Participant

Typical role in the lighting specification process

Architects

Coordinate lighting with the building’s appearance, ceiling systems, materials, and architectural details; may select decorative fixtures and coordinate consultant documents.

Electrical engineers

Address power distribution, circuiting, electrical loads, emergency lighting, energy code compliance, and control integration; often prepare electrical lighting specifications.

Lighting designers

Establish visual and performance goals, develop layouts, evaluate optics and glare, perform or review calculations, and recommend fixtures and controls.

Manufacturer representatives

Provide technical information, samples, photometric files, configuration guidance, and manufacturer pricing or lead-time information for the product lines they represent.

Distributors

Quote and source products, check ordering details, coordinate procurement and deliveries, and identify availability concerns or potential alternatives for review.

Contractors

Evaluate constructability, coordinate field conditions, submit proposed products, purchase through the project’s supply channels, and install and test the system within their scope.

Owners

Define operating needs, budget, maintenance preferences, and facility standards; authorize costs and design changes as required by the contract.

One company may perform several functions. Supplier recommendations support the design team, but do not automatically authorize a product change.

How Do You Create a Commercial Lighting Specification?

Creating a commercial lighting specification starts with defining space requirements, then documenting and validating the fixtures and controls that can meet them. The process develops through design, bidding, construction, and project closeout.

1. Define the Lighting Design Requirements

Lighting design requirements describe what each space needs to support its activities, occupants, and operating conditions.

Identify tasks, operating hours, ceiling heights, daylight availability, desired appearance, and maintenance access. A warehouse aisle and a retail display require different lighting strategies, even within the same building.

Establish the budget and installation milestones early, and check factory lead times for the proposed configurations. Custom architectural linear slots and specialized exterior optics can have long lead times that drive substitution requests. Identify these constraints before selections are finalized.

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2. Establish Lighting Performance Requirements

Lighting performance requirements set measurable targets for illumination, visual comfort, color quality, energy use, and durability.

Document maintained illuminance in foot-candles or lux, uniformity, glare control, color rendering index (CRI), and correlated color temperature (CCT). Maintained illuminance accounts for expected light loss over time.

Use applicable ANSI/IES Recommended Practice (RP) standards from the Illuminating Engineering Society to establish lighting quality targets appropriate to the application.

Identify the governing energy code and adopted edition, which may include ASHRAE Standard 90.1, the International Energy Conservation Code (IECC), or California’s Title 24, Part 6. These address lighting power and controls; they do not replace application-specific illumination criteria. Include voltage, mounting conditions, environmental ratings, and emergency lighting requirements where relevant.

3. Select Fixtures and Validate the Layout

Fixture selection matches product characteristics to the layout, architectural details, electrical infrastructure, and required lighting results.

Photometric data describes how a fixture distributes light. Product-specific IES files allow calculation software to predict illumination using fixture locations, mounting heights, room geometry, and other assumptions. Two fixtures with identical lumen output can produce different light levels and uniformity across a space.

A photometric plan documents calculated lighting results for a proposed layout. It helps the team evaluate coverage and identify areas that need adjustment.

4. Document Fixtures and Specify Controls

The lighting specification package coordinates written requirements, a fixture schedule, drawings, control information, and supporting product data.

A lighting fixture schedule is a table that identifies fixture types and their required configurations, keyed to symbols or tags on the drawings. It typically records manufacturer and model information, output, wattage, voltage, CCT, CRI, mounting, finish, and accessories as appropriate.

Commercial projects commonly organize written lighting specifications under CSI MasterFormat Division 26 (Electrical). Relevant sections include 26 51 00 (Interior Lighting), 26 56 00 (Exterior Lighting), and 26 09 23 (Lighting Control Devices). These establish requirements for product quality, submittals, installation, warranties, testing, and acceptance. Coordinate them with reflected ceiling plans (RCPs), which show ceiling layouts and fixture placement.

When lighting connects to building-wide automation, coordinate applicable Division 25 (Integrated Automation) requirements as well.

Specify controls by describing control zones, occupancy responses, daylight dimming, schedules, manual overrides, and emergency behavior. Identify compatible drivers and control methods, such as 0–10V or DALI, plus programming, testing, and owner training responsibilities.

Define minimum dimming output, such as 1% or 0.1%, and whether the system must fade smoothly to fully off, often called dim-to-dark. Dimming to 0.1% alone does not establish off behavior. Specify linear or logarithmic dimming curves where needed, and verify that drivers and controllers provide the intended response together.

Simplify Your Commercial Lighting Specification Process

Developing accurate lighting specifications is essential to ensuring the right products, performance, and design requirements are incorporated into a commercial project. From evaluating lighting technologies and fixture performance to coordinating product selections and project specifications, the right lighting partner can help architects, engineers, and developers streamline the specification process and avoid costly changes or delays.

Explore our Design Assist & LED Lighting Specification Services to see how Stouch Lighting supports commercial projects with product-neutral expertise and lighting design assistance. Then, visit our extensive Lighting Education Blog Feed for additional insights into lighting technologies, product selection, specifications, and best practices for commercial lighting projects.

👉 Explore Our Design Assist & LED Lighting Specification Services

👉 Explore Our Commercial Lighting Education Blog

5. Review Submittals and Verify Installation

Lighting submittals document the actual fixtures, configurations, and controls proposed for installation so the designated reviewers can compare them with project requirements.

Review exact catalog numbers, dimensions, mounting details, optical data, driver options, accessories, and supporting performance calculations. Confirm factory lead times for the submitted configurations against required delivery dates during submittal review to reduce late emergency value engineering. Clearly identify deviations and follow the required change procedure.

After installation, complete specified inspections, functional testing, control commissioning, and turnover documentation. Keep approved revisions coordinated across project records.

How Do Basis-of-Design Fixtures, Approved Equals, Substitutions, and Value Engineering Differ?

Basis-of-design fixtures establish a design reference, approved equals satisfy required equivalency criteria, substitutions propose a product change, and value engineering evaluates ways to improve project value.

These terms serve different purposes, although their procedures can overlap. The project documents govern what is permitted and who approves it.

Term

Meaning

What the team should evaluate

Basis-of-design fixture

A named product and configuration used to develop the design and establish required characteristics.

Which performance, appearance, dimensions, and integration features alternatives must preserve.

Approved equal

An alternative accepted by the designated authority as meeting the project’s required characteristics.

Evidence of comparable lighting results, quality, physical fit, and control compatibility.

Substitution

A proposed replacement for a specified product, processed under the project’s change requirements.

Deviations, reasons for the request, supporting data, and effects on related work, cost, and schedule.

Value engineering

A structured evaluation of alternatives intended to improve value while maintaining required functions.

Total installed cost, operating expense, maintenance, availability, and any proposed changes to design goals.

Why Doesn’t “Or Equal” Mean Automatic Approval?

“Or equal” allows alternatives to be considered under the specification’s rules; it does not make every similar-looking fixture acceptable.

Listing an alternate manufacturer also doesn't mean you can approve every product in its catalog. Review the proposed model and configuration against required characteristics, using complete optical and driver data. Changes in optics, dimensions, drivers, or mounting can require updated calculations and coordination.

Manufacturers or distributors may bundle fixtures into a single lighting package to reduce cost. Check each package component against the fixture schedule and control requirements. An attractive package price can conceal substitutions that change critical optical performance or driver compatibility.

 

When Does Value Engineering Improve a Lighting Project?

Value engineering improves a lighting project when a documented alternative provides better overall value while preserving required performance.

Standardizing fixture configurations may simplify purchasing and maintenance. Availability can also justify evaluating alternatives when a long factory lead time threatens installation. Compare confirmed delivery dates alongside technical requirements and costs.

A lower unit price may offer little benefit if the alternative requires more fixtures, additional wiring, or ceiling modifications. Include redesign and installation impacts when calculating the proposed savings.

Document the tradeoffs, obtain required approvals, and update affected drawings, schedules, and specifications before implementing the change.

Frequently Asked Questions

Should Existing Fixtures Be Documented Before Specifying a Renovation?

Yes. Record existing fixture types, mounting conditions, circuits, voltages, controls, and emergency provisions. Field verification helps identify constraints that older drawings may not show.

Are Lighting Samples or Mock-Ups Necessary?

Samples or mock-ups are useful when appearance, glare, dimming behavior, or integration details cannot be adequately evaluated on paper. Project documents should identify when they are required and who accepts them.

What Happens if a Specified Fixture Is Discontinued?

The team should identify a replacement and evaluate it through the project’s applicable approval process. A manufacturer’s successor model may have different dimensions, optics, or driver options, so check it before ordering.

Turn Lighting Requirements into a Coordinated Project

A well-developed lighting specification gives the team a clear path from design intent to installation. Defined responsibilities and consistent review criteria help teams resolve product decisions before they disrupt construction.

Specifiers, general contractors, and facility managers can work with Stouch Lighting for design assistance, product sourcing, and procurement coordination. Share your fixture schedule, performance requirements, and installation milestones with our team to discuss product options and supply planning that support your project’s budget and design intent.