Daylight and Sunlight Assessment Reports are more commonly being required for planning applications in areas where buildings are situated close to one another and developments have the potential to affect levels of light to existing building or have restricted light themselves.

Hawkins Environmental have considerable experience in daylight and sunlight impact assessments, according to the Building Research Establishment (BRE) Report 209, "Site layout planning for daylight and sunlight - a guide to good practice" by PJ Littlefair. The BRE Guidelines is accepted methodology for assessing daylight and sunlight and is highly complex. Hawkins have experience in conducting both hand calculations using the Waldram Diagrams, suitable for extensions and small developments, as well as computerized calculations for larger developments. In addition, we can calculate Average Daylight Factors, Vertical Sky Components, or whatever parameter is required to achieve our client's goals.

Hawkins can offer a range of services to assist the developer and architect. They include:

  • Daylight & Sunlight impact assessments for planning applications
  • Overshadowing assessments of outdoor amenity space
  • Daylight calculations for basements and other developments with limited lighting
  • Daylight calculations for the Code for Sustainable Homes and BREEAM
  • Development potential - maximum building envelope assessments
  • Daylight distribution analysis


Daylight, Sunlight and Overshadowing Impact Assessments for Planning Applications

One of our most popular assessments, daylight, sunlight and overshadowing impact assessments are often required in the urban environment when a proposed development has the potential to affect the level of light to existing windows and gardens.

Hawkins Environmental provides a comprehensive package of services relating to daylight impact assessments, including the modeling and calculation of changes to both daylight and sunlight to existing windows, as well as modeling the changes in shadowing of gardens, terraces and other outdoor amenity space, including the presentation of shadow path diagrams. If a development fails to meet the best practice guidance, we can assist is modifying building designs to allow more daylight and sunlight to surrounding windows, we can even conduct maximum building envelope assessments to determine the maximum height of a building in order to be acceptable under the guidance.

Our staff have been conducting daylight impact assessments for a number of years and are familiar with the complex guidance relating to daylight assessment and are aware of the many scenarios and situations where greater reductions in daylight may be permitted.


Internal Daylight Assessments for Planning Applications

In proposed dwellings with restricted daylight availability such as basement dwellings, based on the plans of the proposed development, we are able to determine both the amount of light and its distribution within the rooms in order to determine whether it is deemed adequately lit to the BRE good practice guidelines. Based on the results of our assessments, we can help the architect to alter the design, where necessary to increase daylight availability, including advising on window sizes and room layouts to maximize daylight. Our assessments are often conducted alongside daylight impact assessments.


Code for Sustainable Homes & BREEAM

Hawkins Environmental are able to provide full assessment services to gain credits for the Daylighting elements of both the Code for Sustainable Homes and BREEAM.

Hawkins Environmental is able to give advice and assistance at every stage of the development process, from design advice, to calculation of the Average Daylight Factors and positions of the No-Sky Line, to recommending changes to the design to achieve extra credits. Hawkins Environmental can help gain you credits which will improve your development, reduce carbon emissions and improve people's lives.

To discuss your requirements and for a free consultation, either call 01256 522332 or email plans of your development and your requirements to