Why choose DFL for your Lighting Impact Assessment?

We bring more than just experience – we’re actively involved in shaping industry standards, serving on ILP committees and contributing to the guidelines followed by other lighting consultancies. We also collaborate closely with environmental consultants, ensuring a holistic approach to your project.

When you choose us, you’re not just getting a service; you’re getting a tailored solution. We understand that each project is unique, and we adapt our recommendations to meet your specific needs. Our team provides clear, jargon-free advice and ongoing support throughout the process, including acting as expert witnesses in planning appeals if needed. 

Contact us today for expert advice and tailored solutions.

Lighting Impact Assessment?  What is it?

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.

Types of Developments Requiring Lighting Impact Assessments

Certain developments, especially those involving significant outdoor or street lighting, are often required to submit a lighting impact assessment as part of their planning application. At DFL, we provide LIAs for the following types of projects:

Residential Developments: Particularly near conservation areas, listed buildings, or in areas with existing artificial lighting.

Commercial and Industrial Projects: Retail parks, office complexes, and industrial facilities with extensive outdoor lighting systems.

Sports Facilities: Including stadiums, golf courses, Tennis Courts, Padel Courts, MUGAs and sports pitches.

Infrastructure Projects: Roadways, bridges, and highway lighting installations.

Street Lighting and Motorway Lighting: Projects involving new street lighting, upgrades to existing systems, or motorway lighting installations aimed at improving road safety and reducing light pollution.

Healthcare and Educational Settings: Hospitals, schools, and university campuses.

Outdoor Recreational Spaces: Parks, playgrounds, and public amenities.

Sensitive Ecological Zones: Areas near bat habitats, Sites of Special Scientific Interest (SSSIs), Special Area of Conservation (SACs)  or other ecologically sensitive regions.

By assessing how artificial lighting impacts these environments and proposing suitable mitigation measures, we help ensure that projects proceed without causing unnecessary light pollution or disrupting local ecosystems.

How can a Lighting Impact Assessment from DFL help avoid planning approval delays?

Picture this: you’ve just drawn up a shiny new proposal for an exciting project and sent the document over to the Local Planning Authority for approval.

They say no!

Avoid this by getting a lighting impact assessment from DFL.  We can ensure that your proposal meets all necessary regulations and guidelines, preventing unnecessary delays or rejections in the planning process.

Light Spill infographic

Our Lighting Impact Assessment Process

At DFL, we follow a structured approach to ensure that every lighting assessment we conduct is thorough, accurate, and aligned with the latest industry standards. Our process includes:

Initial consultation and desktop study

We begin by reviewing the proposed project plans and conducting a desktop study. This helps us identify key environmental and human receptors that may be affected by artificial lighting. We also assess existing lighting conditions in the area using aerial photography and mapping tools to create a baseline.

Baseline lighting survey

For a more detailed assessment, we may conduct an on-site survey to measure the existing light levels in the area. Using professional lux metres, our team records light levels at various points around the application site, at night when lighting has the most significant impact.

Environmental and ecological impact analysis

We evaluate how the proposed lighting will affect the environment, considering factors such as:

  • Light Pollution: Sky glow, light spill, and glare.
  • Impact on Wildlife: Especially nocturnal species such as bats, which are sensitive to artificial lighting.
  • Impact on Human Receptors: Nearby residential areas, businesses, and public spaces.

Lighting design and recommendations

Based on our findings, we develop a lighting strategy that minimises environmental disruption while ensuring that the development meets safety and operational requirements. Our recommendations may include adjustments to lighting placement, beam orientation, intensity, and timing (e.g., dimming at night).

What’s included in our comprehensive Lighting Impact Assessment reports?

We provide a detailed Lighting Impact Assessment Report ready for submission with your planning application. This report includes:

  • Baseline lighting conditions and lux measurements.
  • An evaluation of sensitive receptors and environmental zones.
  • Isolux contour maps showing how light spreads across the site and surrounding areas.
  • Mitigation strategies to reduce light pollution and prevent disturbance to local wildlife and residential areas.
  • A summary of compliance with relevant planning policies and standards, including:
    • Professional Lighting Guide PLG 04 – Guidance on Undertaking Environmental Lighting Impact Assessments
    • ILP GN01 – Guidance Notes for the Reduction of Obtrusive Light
    • ILP GN08 – Bats and Artificial Lighting in the UK.
    • BS 5489-1 and BS EN 13201 – Road Lighting Standards
    • National Planning Policy Framework (NPPF)

Q and As (click the icons to find the answers)

An LIA evaluates how a proposed lighting installation affects its surroundings.  This includes both the built environment and natural habitats. At DFL, LIAs are used to demonstrate compliance with planning and environmental regulations and to address conditions set by planning authorities. DFL produce expert assessments that helps smooth the route to planning approval.

LIAs are essential for any project where lighting might impact neighbours, wildlife, or sensitive environments and will require thorough assessment and planning.

Proper lighting design ensures safety, security, and usability while minimising light pollution and environmental disruption. In both urban and rural settings, it is essential that good lighting planning balances human needs with the preservation of dark skies and protection of ecosystems.

In exterior lighting the word ‘photometry’ relates to the light output from a specific product and how it falls on the road. With different lumen packages and optics, each option and output should have its own unique photometric file. Sometimes, photometry may be described as relative or absolute. Absolute photometry is always the most accurate!

DFL designs schemes that meet safety and use goals while reducing ecological and light pollution. They carefully select fixtures with targeted beam spreads, apply shielding like louvres, and ensure light levels stay within regulatory lux limits. This is done through technical modelling combined with planning controls and environmental best practices.

We typically provide a lighting level survey of the existing illuminance and a technical report to summarise our findings. The report will identify a suitable lighting class for the installation and we compare our findings against the standards identified. We’ll also provide our professional opinion on the installation, as well as tips on how to improve your existing scenario, which may cover energy saving measures, glare reduction, light spill control, electrical recommendations, the addition of colour and smart switching arrangements. We may also be able to provide advice and guidance on how your installation could generate a passive income for you.

We can’t change the laws of physics (yet!), but we can choose the best luminaire and put it in the best position to maximise the useful light and minimise the light spill. We can tell you where the spill light will be, horizontally and vertically, and explain what effect it’ll have – if any. It might sound obvious, but its our job to make sure we only put the lighting where you need it.

We’ll try to be to the point with this one. A lighting strategy talks about how the lighting you plan to install will follow a palette of materials and stay in keeping with the development or surrounding area – referencing the standards and guidance the design principles will follow. A technical report’s a way of demonstrating what a proposal or existing installation is achieving and how that relates to standards, with a professional conclusion presented at the end. Finally, a lighting impact assessment looks at what the impact of the proposed lighting will have on the development when considering the current baseline conditions.

Here’s a few Links you might find useful

UK Government Guidance on Light Pollution

GOV.UK Planning Practice Guidance: Light pollution
UK Government Guidance

BCT & ILP Guidance Note GN08/23 – Bats and Artificial Lighting at Night

Bat Conservation Trust & Institution of Lighting Professionals joint guidance
GN08/23

LIA Standards and Guidelines

Our lighting assessments are designed to meet and exceed industry standards. We’re one of the UK’s largest independent lighting consultancies, and we do LIAs day in, day out (they’re kind of our thing!). Our experts are clued up on all the latest Institution of Lighting Professionals (ILP) guidelines and industry standards required to get the planning authorities on your side.

These guidelines help us ensure that all lighting designs are safe, energy-efficient, and environmentally friendly.

village drawing with quote

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