Introduction

KJ Tait Engineers were appointed by Galliford Try to carry out an assessment of the daylight available to a proposed new Special School

The assessment included:

• Climate Based Daylight Modelling (CBDM) to all teaching spaces in accordance with the guidelines of the Educational and Skills Funding Agency (ESFA)
• Average Daylight Factor (ADF) to all other occupied spaces in accordance with Lighting Guide 5 (LG5).

Key Outcome:

The aim was to calculate the usable lighting within all teaching areas using the Climate Based Daylight Modelling (CBDM) technique calculating the UDI-a and sDA. These are then assessed against the Educational and Skills Funding Agency (ESFA) requirements.

Due to the close proximity of 16m high trees we had to carry out a number of calculations to achieve a solution that met the requirements of the ESFA.

The only way to obtain the 80% to pass was to introduce additional rooflights on first floor rooms as the ground floor classrooms adjacent the trees were an issue.

This exercise was important for the planning submission due to the landscaping strategy impacting on the daylight and architectural design.  This required the team to work together to find a compromise solution.