Daylight and Sunlight Assessments are required by planning authorities to check that new developments provide good daylight inside rooms and do not negatively affect neighbouring windows or gardens.
For internal assessments, we follow BS EN 17037 to measure daylight distribution and sunlight exposure.
For external assessments, we follow BRE 209 to assess neighbour impact, including VSC, APSH, and overshadowing.
Our assessments use trusted methods, following the BRE Guide: Site Layout Planning for Daylight and Sunlight - A Guide to Good Practice, 3rd Edition (2022) by P.J. Littlefair, with clear reporting to help your project achieve the right daylight and sunlight levels and gain planning approval without delays.
Our dedicated professionals ensure thorough and accurate assessments for each project. We are steadfast in our commitment to delivering clarity and understanding for out clients.
Most UK local authorities require a Daylight and Sunlight assessment if your development is multi-storey, located near existing residential windows, or significantly larger than the building it replaces. Enviropass provides the technical reports needed to validate your application and prove that your scheme respects the "amenity" of the local area.
BRE 209 is the industry-standard "Guide to Good Practice" used by planning officers to judge light impact. The 2022 update introduced stricter alignment with European standards. Enviropass ensures your project is assessed against these latest benchmarks, preventing your application from being judged by outdated—and therefore invalid—criteria.
The cost depends on the number of "receptors" (neighbouring windows) and the complexity of the 3D model. Enviropass offers competitive, transparent fee structures. We focus on delivering high-accuracy environmental consultancy services that provide real value by de-risking your planning journey.
VSC is the primary measure of "skylight" reaching a window. If a new development reduces a neighbour’s VSC to below 27% (or less than 0.8 times its former value), it often triggers a planning objection. Enviropass uses advanced 3D modelling to calculate exact VSC levels, providing the data needed to justify your building's massing.
The 45-degree rule is a "rule of thumb" used by planners to spot potential light issues. If you fail this, you will likely need a formal Daylight and Sunlight assessment to prove that the actual impact is acceptable. Enviropass specializes in these detailed studies, often proving that a "rule of thumb" failure doesn't necessarily mean a loss of amenity.
This is a critical distinction: Daylight and Sunlight is a planning matter (amenity), while Right to Light is a legal matter (easements). Enviropass focuses on the planning side, ensuring your project meets local authority requirements to get your permission granted, while advising on potential legal risks.
APSH measures the amount of direct sunshine a window receives throughout the year. For a room to be "well-lit," it typically needs 25% of annual hours, including 5% in winter. Enviropass provides these precise calculations to ensure your development offers a high standard of living for future occupants.
Yes, the BRE guidelines state that at least 50% of an amenity space should receive at least two hours of sunlight on the 21st of March. Enviropass produces shadow plots and "Sun-on-Ground" diagrams that clearly demonstrate your project won't leave neighbouring gardens in the dark.
Absolutely. By conducting "massing studies" early, Enviropass can help you determine the maximum possible height and "bulk" of a building before it starts to negatively impact neighbours. This allows you to maximize your site's GDV (Gross Development Value) while remaining within planning limits.
The NSL test tracks which parts of a room can "see" the sky. If the area of the room that can see the sky is reduced significantly, the council may view the development as harmful. Enviropass provides internal daylight distribution maps to help you optimize window placement and room layouts.
Trees are generally not included in the "baseline" because they can be removed or die. However, they are increasingly considered in "mitigation" discussions. Enviropass can provide a nuanced analysis that balances your ecological surveys and BNG plan with your daylight requirements.
Sometimes. High-density planting for a BNG plan can shade lower-floor windows. As a multi-disciplinary environmental consultancy, Enviropass ensures your landscaping strategy and daylight strategy work in harmony, preventing one environmental benefit from causing a planning failure elsewhere.
ADF was the old way of measuring internal light. Under the new 2022 standards (BS EN 17037), we now look at "Target Illuminance" across the room. Enviropass uses these modern metrics to ensure your new homes are bright, airy, and compliant with current Building Regulations.
Depending on the size of the project, a professional report usually takes 5 to 10 working days. Enviropass offers a rapid turnaround service to meet tight planning deadlines, ensuring your technical data is ready for the committee.
Yes, and they are high-risk. Subterranean units often struggle to meet light targets. Enviropass uses "Climate-Based Daylight Modelling" (CBDM) to prove that through lightwells and reflective surfaces, even basement units can provide high-quality habitable space.
CBDM is a sophisticated simulation that uses real weather data to predict light levels every hour of the year. Enviropass uses this to provide a more realistic and "defensible" data set than simple static tests, which is often a key factor in winning appeals.
Yes. If a neighbour objects based on "loss of light," a professional report from Enviropass often proves their concerns are exaggerated or that the impact remains within BRE-accepted thresholds, giving the planning officer the evidence they need to approve your scheme.
The BRE guidelines suggest that a 20% reduction is "noticeable." However, in dense urban areas like London, higher reductions are often considered "acceptable" due to the context. Enviropass provides the written justification to help planners apply "flexibility" to your project.
While the focus is usually on residential properties, offices and schools also require adequate light. Enviropass assesses commercial schemes to ensure they provide a productive work environment and comply with BREEAM standards.
Deep balconies can severely restrict light to the units beneath them. Enviropass works with your architects to "stagger" balconies or use glass balustrades, ensuring you meet your BNG plan requirements for outdoor space without failing your daylight tests.
This is a video-style simulation showing exactly where a shadow falls throughout the day. Enviropass produces these visual aids to help planning committees—and local residents—visualize the actual impact of a tall building, often de-escalating local opposition.
The rules are the same, but the "flexibility" is often higher. Enviropass understands how to frame your Daylight and Sunlight assessment within the context of heritage and high-density urban living, helping you win approval in sensitive locations.
If you are building near an existing development, you are the "Agent of Change." You must ensure your building doesn't unfairly restrict their existing light. Enviropass protects your legal and planning position by assessing these impacts before you submit.
Yes. Many councils now require daylight proof for "office-to-residential" conversions to ensure they aren't creating "substandard" housing. Enviropass provides these fast-track reports to secure your Prior Approval quickly.
Because we don't just provide "Fail" or "Pass" marks—we provide solutions. If your design fails a test, Enviropass will suggest the "massing tweaks" or window changes needed to get it over the line. We are your partners in planning success.
For those exploring "Daylight and Sunlight Assessments & Reports near me," we're proud to serve the entirety of the London region. We hold each project to the highest standards of quality and compliance.
For a deeper dive into Planning Applications in London, consider visiting The City of London's Official Planning Website.
