Herrington’s specialist Light team works on projects ranging from private builds and extensions, high rise developments and new build housing estates to conversions of basesments and offices to residential use. We work with home owners, architects, developers, retailers, local authorities, and planners. When you need help delivering your project on time with the optimal commercial outcomes whilst also meeting the required daylighting needs, our team of experts is always happy to talk you through and advice on the technical requirements needed for planning.
Designing for Light
We can assist with assessing the potential impact on natural light to neighbouring properties and the internal availability of natural light within new residential schemes, amongst other services. We have extensive experience in delivering complex technical reports for challenging projects using our expert 3D modelling capabilities. We can provide expert advice on scheme cutbacks for sensitive areas, maximum envelope studies to best utilise development sites and internal layout reconfigurations to meet minimum light standards in residential developments.

Daylight and Sunlight Assessment
Daylight and Sunlight Assessments can be used in a number of ways to improve the design of a scheme at all stages in the design process, for example scoping out development potential and identifying specific site constraints, or quantifying daylight and sunlight provision inside new dwellings.
Impact on Neighbours
In line with the recommended methodology set out within the BRE Guidelines (BR209 Third Edition 2022), the Vertical Sky Component (VSC), Daylight Distribution/ No Sky Line (NSL) and Annual Probable Sunlight Hours (APSH) tests are calculated. Our analysis is carried out using a 3D model of the existing, proposed, and surrounding developments and simulations are undertaken for both the ‘existing’ and ‘proposed’ development scenarios.
We can help with:
- Maximum envelope/jelly mould studies
- Cut backs to achieve BRE compliant schemes whilst maximising development within the site boundaries
Internal Provision of Light
In line with the recommended methodology set out within the BRE Guidelines, the Daylight Factor, Daylight Illuminance and Sunlight Exposure tests are carried out. Our analysis is carried our using a 3D model of the proposed and surrounding developments as well as closely located trees and other vegetation.
We are experts in providing advice to improve natural light to meet the recommended standards.
Overshadowing Studies
In addition to the BRE Sun on Ground test, we can provide Transient Overshadowing studies.
This study focuses on the shadows cast by new developments and are typically undertaken to assess the impact on amenity spaces such as gardens and public open spaces. The objective is to simulate the path and extent of shadows cast by new developments at hourly intervals at different times of year. The outputs are graphical rather than numerical and therefore require careful interpretation.
BREEAM
We can also undertake analysis to meet the BREEAM requirements for daylight provision within proposed new internal spaces such as residential dwellings, educational facilities, hotels, hospitals and student accommodation.
Up to two BREEAM credits are available for ‘Daylighting’ under Hea01. This aims to encourage good natural light is considered in building design, reducing the need to artificial light and improving visual comfort and wellbeing.
What our Clients say
Private Client“I have to say it is had been a very smooth process from start to finish.
I definitely plan to use yourselves again on future projects.”
External Light
For new developments there is now an opportunity for planning authorities to impose conditions related to external lighting, including curfew hours. In recognition of the growing need to assess and mitigate environmental impacts, Herrington Consulting can include Light Pollution/Light Impact Assessments as one of the Planning Assessment services we offer.


External Light Impact Assessment (ELIA)
There are many forms of light pollution and these are generically referred to as ‘obtrusive light’, which if not properly controlled can have physiological and ecological impacts. Since 2006, artificial light has been included on the list of possible Statutory Nuisances in England, Wales and Scotland and is also now referenced in both National and Local planning policy. We are able to undertake detailed External Lighting Impact Assessments that allow lighting schemes to be tested and potential adverse impacts identified and mitigated.
Why the need to assess?
An external light impact assessment is typically required for planning applications to ensure that the NPPF policy on light pollution from artificial lighting to local landscapes is met. Local Planning Authorities mainly follow the guidelines for external lighting installations set by the Institutions of Lighting Professionals (ILP) Guidance Note 1 ‘The Reduction of Obtrusive Light’ and ILP Guidance Note 08/23 – Bats and Artificial Lighting in the UK.
Planning considers:
- The maximum lux for LED lights
- The colour rendering indices of light sources below specified maximum values
- The main beam angle of all lights within specified tolerances
- Environmental Zones in the area surrounding the development (will determine their sensitivity to external light sources)
We promote a commercially balanced, phased approach to external light assessment with initial scoping assessments which may be used to address planning conditions in low sensitivity locations or to support a planning application, followed by more design / receptor specific assessment and lighting constraint modelling where an issue has been identified requiring a higher level of consideration.

We use numerical modelling techniques to analyse a range of lighting impacts or light pollution. This is a very general term which refers to the effect of over-lighting resulting from poorly designed lighting schemes and excessive levels of light. When external lighting installation requires impact assessment, be it in terms of glare or even potential impact on wildlife, our team of experts can help ensure your design is right.
We can help with:
- Light Trespass and Light Spill
- Luminaire Intensity
- Landscape Impacts
- Assessment of potential impacts on foraging and commuting bats, carried out in line with the ILP Guidance Note 08/18 – Bats and artificial lighting in the UK
Solar Glint and Glare
Glint and Glare Assessments are technical evaluations conducted to understand the potential impact of reflective surfaces, such as solar photovoltaic (PV) panels, on the surrounding environment. These assessments are often required to support planning permission, for ensuring that new developments are designed with consideration for their environmental and social impact. They are particularly important for developments that include solar PV installations or buildings with large glass surfaces and/or are located near infrastructure such as airports or railways.

Why the need to assess?
“Glint and glare” is the general term used to describe the reflection of sunlight from a reflective surface, typically one that is capable of producing specular solar reflections. Glint is defined as a momentary flash of bright light typically received by moving receptors or from moving reflectors, whilst glare is a continuous source of bright light, typically received by static receptors or from large reflective surfaces.
Solar glint and glare is a phenomenon caused by the concentrated source intensity of light and it can manifest in the built environment when the sun is reflected off infrastructure or building façades. In certain situations the scattering of light inside the eye can become visually disabling resulting in impaired vision. This impairment can present particular hazards to pilots, and drivers of vehicles and trains, and needs to be assessed.
The Solar Glint and Glare Assessment quantifies the potential for this disabling glare to present unacceptable risks in the vicinity of a building or infrastructure such as solar panels.
How we work
Herrington promotes a commercially balanced, phased approach to all types of lighting assessment with initial scoping assessments which may be used to address planning conditions in low sensitivity locations or to support a planning application, followed by more design / receptor specific assessment and constraint modelling where an issue has been identified requiring a higher level of consideration. Using industry proven modelling techniques and software to model for scenarios such as an aircraft on final approach or a train driver as they pass a signal, if a potential risk is identified, Herrington works with the team and the client on layout modifications (such as changes to panel tilt and elevation angle) which can often alleviate concerns and overcome objections. Our approach is to be comprehensive but cost effective and importantly, be team players for the wider project.
