A Lighting Impact Assessment is a detailed evaluation of how artificial lighting from a proposed or existing development may affect the surrounding area. This includes analysing light pollution, glare, and the impact on both ecological and human receptors. 

Such assessments are essential for ensuring compliance with local and national planning policies, especially for developments near sensitive environments like conservation areas, wildlife habitats, and residential neighbourhoods.

We specialise in delivering professional lighting assessments that help guide your project smoothly through the planning process.

Many planning authorities now expect applicants to demonstrate that lighting has been designed with biodiversity in mind. Ecological lighting is becoming a key consideration where developments are located near bat commuting routes, woodland edges, watercourses, hedgerows, protected species, or designated ecological sites. Addressing these issues early can significantly reduce planning delays and costly redesigns.

Artificial light at night can have a significant impact on wildlife, altering natural behaviour, disrupting feeding and breeding patterns, and fragmenting important ecological corridors.

At DFL, ecological lighting design is integrated into every stage of the project. We work alongside ecologists, planners and design teams to ensure lighting achieves its purpose while protecting the natural environment.

Our assessments consider the potential effects of artificial lighting on:

• Bats and their commuting and foraging routes
• Owls and other nocturnal birds
• Badgers, dormice and other protected mammals
• Rivers, ponds and aquatic habitats
• Woodland edges, hedgerows and ecological corridors
• Rural landscapes and Dark Sky environments
• Sites of Special Scientific Interest (SSSIs), Special Areas of Conservation (SACs) and other designated habitats

Typical mitigation measures include:

• Carefully directing light only where it is needed
• Selecting warmer colour temperatures where appropriate
• Minimising light spill beyond the development
• Reducing mounting heights
• Intelligent controls, dimming and curfews
• Shielding luminaires to preserve dark habitats

The result is lighting that supports planning approval while protecting biodiversity and reducing unnecessary light pollution.

We do not just produce reports – we help you secure planning approval.

With DFL, you benefit from:

• Planning-focused Lighting Impact Assessments
• Environmental lighting design expertise
• Clear, actionable recommendations
• Fast turnaround times
• Support throughout the planning process

We are actively involved in shaping industry standards, contributing to ILP guidance and working alongside environmental consultants to deliver fully integrated solutions.

We provide Lighting Impact Assessments and lighting strategies for:

• Residential developments
• Commercial and industrial sites
• Sports lighting schemes
• Infrastructure and highways
• Educational and healthcare facilities
• Public realm and recreational spaces
• Ecologically sensitive developments requiring wildlife-friendly lighting

A Lighting Impact Assessment evaluates how artificial lighting from a development affects its surroundings. Where ecological receptors are present, the assessment also considers how artificial light could affect protected species, ecological corridors and sensitive habitats, identifying mitigation measures that support both planning compliance and biodiversity conservation.

This includes:

• Light spill and sky glow
• Glare and visual intrusion
• Impact on neighbouring properties
• Effects on wildlife and habitats

It demonstrates compliance with planning policy and ensures your scheme aligns with best practice in environmental lighting design.

Our Approach

We make the process efficient and planning-focused:

1. Review of your plans – We assess layouts and identify environmental and planning risks
2. Baseline assessment – Desktop analysis and, where required, on-site surveys
3. Technical modelling – We model light distribution and environmental impact
4. Ecological Lighting Design – We develop practical mitigation measures that minimise the impact of artificial light on wildlife while maintaining safe, functional lighting for users. This may include revised luminaire selection, optical control, dimming strategies, curfews and alternative lighting layouts.
5. Planning-ready report – Clear, compliant documentation for submission

What’s included in your report?

Your Lighting Impact Assessment will include:

• Baseline lighting conditions and measurements
• Identification of sensitive ecological and human receptors
• Isolux contour plans showing light distribution
• Assessment of light spill, glare, and sky glow
• Ecological lighting recommendations and mitigation strategies
• Compliance with key standards, including:
  • ILP GN01 (Obtrusive Light)
  • ILP GN08 (Bats and Artificial Lighting)
  • PLG04 Guidance
  • BS 5489 and BS EN 13201
  • National Planning Policy Framework (NPPF)

Ecological lighting is no longer considered a niche discipline. Across the UK, planning authorities are placing greater emphasis on protecting biodiversity and reducing the effects of artificial light at night.

Developments located close to woodland, watercourses, green infrastructure, protected species or designated landscapes are increasingly expected to demonstrate that lighting has been carefully designed to minimise environmental impacts.

By considering ecological lighting at the earliest stages of design, developers can:

• Reduce planning risk
• Avoid expensive redesigns
• Protect biodiversity
• Minimise light pollution
• Create more sustainable developments
• Improve long-term environmental performance

At DFL, we believe good lighting should illuminate spaces for people while respecting the wildlife that depends on darkness.