Step 1 — Define the Project Objectives

Before selecting any products, establish what the lighting needs to achieve for each space:

• The primary purpose of each zone — task lighting, ambient, accent, wayfinding, safety
• The target atmosphere — formal and bright (retail), warm and intimate (hospitality), neutral and focused (office)
• Operational hours — how many hours per day, whether occupancy-linked control is needed
• Flexibility requirements — does the space need to serve multiple functions with different scenes?
• Maintenance access — how easily can fittings be reached for relamping or cleaning?

Step 2 — Set the Performance Requirements

Performance requirements translate objectives into measurable targets. For each zone, define:

Metric	Guidance
Maintained illuminance (lux)	Minimum lux level at the working plane after depreciation
Uniformity ratio	CIBSE recommends 0.7 or better for working environments
Colour rendering index (CRI)	Minimum 80 for most commercial; 90+ for retail and hospitality
Colour temperature (CCT)	2700–3000K hospitality; 3500–4000K office and retail; 5000K+ technical
Glare limitation (UGR)	UGR 19 or below recommended for office environments
Energy target	Watts per square metre or LENI target for sustainability requirements

Step 3 — Identify Compliance Requirements

• Building Regulations Part L — minimum energy efficiency requirements for new builds and significant refurbishments
• CIBSE Lighting Guide LG7 — the standard reference for office lighting design in the UK
• BREEAM / LEED — lighting contributes through energy efficiency, occupancy controls, and daylighting integration
• Fire safety — fire-rated downlights required in floor-to-ceiling applications; emergency lighting must meet BS 5266
• IP ratings — any fittings in wet areas must meet the appropriate IP rating for the zone

Step 4 — Specify the Control System

• The dimming protocol — 0–10V, DALI, DMX, Casambi, or on/off only
• Scene requirements — how many scenes per zone, what the default states are
• Occupancy and daylight sensing — which zones require sensors, mounting positions, and hold times
• Emergency override — how emergency lighting integrates with the main system
• BMS integration — what DALI gateway or protocol bridge is required if applicable

Step 5 — Select and Specify Products

For each product the specification should record:

• Product name and manufacturer reference — e.g. Lumily LED LLS Series 24V, 14W/m, 4000K
• Photometric data — manufacturer IES or LDT file for verification in lighting simulation software
• CRI, CCT, lumen output, and lumen maintenance data — L70 or L90 at 50,000 hours
• Driver specification — model, wattage, dimming protocol, IP rating
• IP rating and warranty period
• Energy label classification where applicable

Step 6 — Write the Sustainability Section

• Energy consumption target — maximum watts per square metre for each zone category
• Control strategy — occupancy sensors, daylight dimming, scheduled off modes
• Product lifespan — LED products should have a rated lifespan of at least 50,000 hours L70
• Light pollution — for exterior lighting, specify curfew dimming, directional control to prevent upward light spill, and compliance with CIBSE Guidance Note 8
• Responsible sourcing — products must comply with RoHS and WEEE regulations

Step 7 — Budget and Procurement

• Provide a product schedule listing quantities, unit prices, and total supply cost
• Specify lead times — particularly for custom-length profiles, pre-wired assemblies, or bespoke driver configurations
• Define substitution rules — whether equivalent products from alternative manufacturers will be considered, and what approval process applies
• Include installation notes — any specific requirements for profile mounting, driver enclosure, or cable management