How Clients and Consultants Are Using TM66 Scoring in Tenders
TM66 has rapidly moved from a technical discussion point to a formal procurement requirement in many lighting tenders. For clients, consultants, and facilities managers, it is increasingly used as a practical way to assess circularity, sustainability, and long-term value—beyond simple energy performance or upfront cost.
This article explains what TM66 is, why it matters in procurement, and how it is being applied in real-world tender decisions.
What Is TM66?
TM66 is a CIBSE methodology designed to assess the circularity of luminaires. Rather than focusing solely on energy efficiency, TM66 evaluates how a lighting product is designed, manufactured, maintained, and ultimately reused or recycled.
The assessment produces a TM66 Circularity Score, which reflects factors such as:
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Ease of disassembly
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Replaceability of components
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Availability of spare parts
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Material selection and recyclability
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Product longevity and upgrade potential
For procurement teams under pressure to demonstrate sustainability credentials, TM66 offers a structured and auditable framework.
Why TM66 Matters in Procurement
Lighting procurement has shifted. Energy efficiency is now considered a baseline requirement, not a differentiator. Increasingly, tenders are asking:
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Can this product be repaired rather than replaced?
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What happens at end of life?
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How does this align with ESG and Net Zero commitments?
TM66 provides a common language for answering these questions and comparing products objectively.
How TM66 Is Being Used in Tenders
TM66 is appearing in tenders in several distinct ways.
1. Minimum Threshold Scores
Some clients specify a minimum TM66 score that luminaires must achieve to be considered compliant. Products below this threshold are excluded at the technical evaluation stage.
2. Weighted Evaluation Criteria
Other tenders use TM66 as part of a weighted scoring system, where circularity contributes alongside:
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Energy performance
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Cost
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Warranty and lifespan
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Embodied carbon
3. Evidence of Circular Design Intent
Even where a formal score is not mandated, many consultants now request TM66-style evidence to demonstrate that circularity has been actively considered.
TM66 and Retrofit Lighting
Retrofit lighting aligns naturally with TM66 principles.
By retaining the existing luminaire housing and replacing only the necessary internal components, retrofit solutions typically score highly against TM66 criteria related to:
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Reuse of existing assets
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Reduced material consumption
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Extended product life
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Minimised waste
For many projects, retrofit achieves circularity outcomes that would be difficult for entirely new luminaires to match.
What Consultants and Clients Are Looking For
When reviewing TM66-related submissions, evaluators typically focus on:
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Clear explanation of how components can be accessed and replaced
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Availability of replacement drivers, LED boards, and batteries
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Evidence that upgrades can be carried out in situ
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Transparent material and recycling pathways
Generic sustainability claims are increasingly challenged. Documentation and traceability matter.
Common Pitfalls in TM66 Submissions
Some frequent issues seen in tender responses include:
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Quoting TM66 scores without supporting evidence
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Confusing energy efficiency with circularity
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Failing to explain how a product would actually be upgraded or repaired on-site
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Relying on manufacturer statements rather than project-specific solutions
Well-prepared submissions address these points clearly and concisely.
TM66 as a Decision-Making Tool, Not a Tick-Box
While TM66 is a powerful framework, it is most effective when used to support better technical decisions, not simply to meet tender requirements.
Projects that genuinely engage with TM66 tend to achieve:
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Lower whole-life costs
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Improved maintainability
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Reduced embodied carbon
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Greater alignment with long-term sustainability goals
TM66 is reshaping how lighting is specified, evaluated, and procured. For clients and consultants, it offers a structured way to move beyond short-term performance metrics and assess the long-term value of lighting assets.
As TM66 becomes more embedded in tender documentation, solutions that prioritise reuse, upgradeability, and longevity, including retrofit approaches, are increasingly well placed to meet both technical and sustainability expectations.
