A daylight assessment was carried out for the proposed basement bedrooms in the new dwellings. Our report outlined the results of the assessment in order to assist with the developments planning application.
The methodology used for the assessment followed the most recognised guidance document for daylight and sunlight within dwellings and is titled ‘Site Layout Planning for Daylight and Sunlight – A Guide to Good Practice’ Second Edition 2011; by Paul Littlefair and is published by the Building Research Establishment.
Our report investigated the natural light received by the proposed basement bedrooms. The following daylight assessments were carried out with the use of computer modelling software in order to provide the most accurate results possible.
- Vertical Sky Component (VSC)
- No Sky Line / Daylight Distribution
- Average Daylight Factor
The VSC results showed that the view out from each of the windows would not meet the required 27% VSC value, however this was to be expected from a proposed basement bedroom window. As this was to be expected, and as the bedrooms will be receiving light from multiple windows we considered the assessment of the VSC values to only be Minor Adverse.
The Daylight Distribution results showed that the bedrooms would have a value of 86.6%, greater than the recommended target of 80%. Therefore the distribution of daylight across the bedrooms was assessed as Good.
The average daylight factor results showed that the bedrooms will have a value of 1.21%, greater than the minimum required level of 1% as set by the British Standard BS 8206-2:2008, Lighting for Buildings – Part 2: Code of Practice for Daylighting and referenced within the BRE guide. Therefore the daylight factor of the Bedrooms was described as Good.
In summary the daylight assessment of the proposed basement bedrooms showed that although the view out from the bedroom windows is less than what is recommended, this was to be expected from a bedroom located within a basement. The additional daylight tests carried out showed that the bedrooms will make excellent use of the daylight they do receive, as the bedrooms surpass the daylight distribution and average daylight factor target values. Therefore we considered the proposed basement bedrooms to be satisfactory in terms of daylight.