Most lighting problems that surface on site, wrong products, non-compliant schemes, budget overruns, and disappointed clients, can be traced back to a poorly written or entirely absent lighting brief. For architects and interior designers who commission lighting expertise rather than deliver it themselves, knowing how to write a clear and complete brief is one of the most commercially valuable skills you can develop.
This guide explains exactly what a lighting brief should contain, why each element matters, and how getting it right early in the project saves time, cost, and difficult conversations later.
If you are not yet familiar with how lighting performance requirements translate into specification language, it helps to read How to Read a Lighting Specification: A Beginner's Guide for Designers alongside this guide.
A lighting brief is not a product specification. It does not name luminaire models, brands, or catalogue numbers. It defines the desired outcomes: how each space should feel, what tasks will be performed there, what standards and compliance obligations apply, what constraints exist, and what the client values most.
The brief is the foundation on which the specification is built. A good brief given to a lighting supplier or consultant at RIBA Stage 2 or Stage 3 produces a better, faster, and more compliant scheme than a vague instruction passed to a contractor at tender stage. It also gives the client a clear document against which to evaluate the design, which makes approval conversations significantly more straightforward.
Think of the brief as the document that answers the question: what does this lighting need to achieve? The specification that follows it answers the question: how will it achieve it?
List every room or zone within the project, its primary use, and its occupancy pattern. This sounds obvious, but it is frequently omitted or left at too high a level of generality to be useful.
A space used for multiple purposes needs to be flagged explicitly. A boardroom that doubles as a presentation space and an informal breakout room has three distinct lighting needs. A hotel bedroom that must serve as a working, relaxing, and sleeping environment has different requirements from a bedroom used only for overnight stays. If the brief does not capture that complexity, the scheme cannot be designed to address it.
Also note any spaces with unusual occupancy patterns, areas used 24 hours a day, spaces that are infrequently occupied, or zones with seasonal variation in use. These affect both product selection and controls strategy.
Use plain language to describe how each space should feel. Words like warm, intimate, energising, calm, clinical, focused, celebratory, or welcoming are more useful starting points than lux figures, because they capture the intent behind the requirement rather than just the measurement.
Reference precedents wherever possible. If the client has visited a hotel lobby, restaurant, or office that felt right to them, that reference is worth more than a paragraph of description. Images, mood boards, and completed project references all help translate a subjective brief requirement into an objective design direction.
Be specific about what the client does not want as well as what they do. A brief that says “warm and welcoming, not clinical or corporate” is more useful than one that says “warm and welcoming” alone.
Note any standards, guidance documents, or compliance obligations that apply to the project. Common examples include:
You do not need to be an expert in all of these documents to include them in a brief. Noting that they apply is sufficient, the lighting designer or supplier will interpret the requirements. What matters is that they are flagged early rather than discovered late.
For reference, our guides on emergency lighting law and office lighting regulations provide useful background on the compliance landscape for these sectors. See What Is Emergency Lighting Law in UK Commercial Buildings and Office Lighting Regulations and How to Comply.
The physical environment of the building places real constraints on what luminaires are feasible. A brief that does not communicate these constraints produces a design that looks good on paper and fails at installation.
Include the following in your brief for each zone:
Ceiling height in particular has a significant effect on product selection, beam angle requirements, and achievable lux levels. A scheme designed for a 2.7 metre suspended ceiling requires completely different luminaires to one designed for a 5 metre exposed structure, even if the performance targets are identical.
Lighting controls are one of the most frequently underspecified elements of a project brief, and one of the most consequential to get wrong. Controls decisions affect product selection, driver specification, wiring design, M&E coordination, and cost, all of which need to be understood before tender stage.
At minimum, a brief should state:
A brief that says simply “lighting controls to suit” leaves all of these decisions to the contractor, which typically means the cheapest available option rather than the most appropriate one.
For background on controls options and their implications, see DALI vs 0–10V vs Smart Lighting and Building Management Systems and Lighting Control Integration.
Lighting budgets are set without reference to what the specified scheme actually costs more often than any other building services element. The result is either a scheme that gets value-engineered beyond recognition at tender stage or a contractor substitution process that undermines the design intent.
A brief does not require a precise figure, but it should communicate the range and the hierarchy of priorities. Distinguishing between contractor-grade, mid-market architectural, and high-specification bespoke gives a supplier or consultant enough information to build a scheme that reflects the client's actual position rather than an assumed one.
It also helps to indicate where within the project the lighting budget is most important. A hospitality client may want to concentrate spend on the restaurant and bar while accepting a more modest specification in back-of-house. An education client may prioritise teaching spaces over corridors. Communicating these priorities at brief stage means the available budget is allocated where it has the most impact.
Sustainability requirements now affect lighting specification decisions on most commercial projects. If the brief does not mention them explicitly, they are likely to be reduced to generic statements about LED efficiency, which is no longer enough for many clients or project teams.
At minimum, note whether the project is pursuing BREEAM, WELL, NABERS UK, or internal net-zero carbon targets. If the client is concerned with embodied carbon, circular economy principles, reuse of existing fittings, or Environmental Product Declarations, those priorities need to appear in the brief from the outset.
This is also the stage to state whether daylight harvesting, occupancy detection, zoning, and metering are expected as part of the controls strategy. These decisions affect compliance with Part L and influence the overall system architecture.
One of the easiest ways to derail a lighting project is to leave the approval route unclear. A design can appear to be progressing well, only to stall when a facilities manager, end user, client representative, heritage officer, or contractor raises an objection late in the process.
Your brief should therefore identify who needs to sign off the concept, who has authority over budget decisions, who is reviewing controls usability, and who will ultimately live with the installation after handover.
This matters because different stakeholders judge lighting in different ways. A client may focus on aesthetics and budget. Facilities teams may prioritise maintenance access, emergency testing, and ease of control. M&E consultants may focus on compliance, energy and integration. Capturing these priorities early makes the design process more efficient and reduces contradictory feedback later on.
The best lighting briefs are produced early, ideally at RIBA Stage 2 while the concept design is still open to influence, and certainly before the project reaches a tender stage where meaningful design changes become expensive.
By Stage 4 or Stage 5, the cost of correcting an incomplete brief is far higher. Ceiling types may already be fixed. Controls infrastructure may already be coordinated incorrectly. Budget expectations may already be set against the wrong quality level. The later the issue is discovered, the more likely it is to end in compromise.
If you want a practical starting point, make sure your brief answers the following questions:
If a brief answers those questions clearly, the lighting designer or supplier has the information needed to develop a scheme that is much more likely to succeed first time.
A good lighting brief is not just an administrative document. It is a commercial risk-reduction tool. It reduces redesign, avoids inappropriate substitutions, supports compliance, improves coordination with M&E and architecture, and gives the client a clearer route to approving the scheme.
For architects and interior designers, that matters because lighting is one of the building elements most likely to be judged emotionally by the client and operationally by the end user. When it goes wrong, it is noticed quickly. When it is briefed properly from the start, it supports the wider project quietly and effectively.
At 299 Lighting, we work with architects, designers, consultants and contractors to turn early-stage lighting intentions into clear, buildable schemes. If you are preparing a brief for an office, hospitality, education, retail or mixed-use project, we can help you shape the right information before specification begins.