Daylight & Sunlight Assessments for Planning

Herrington Consulting are specialist Daylight / Sunlight and External Light Pollution consultants. We work on projects ranging from individual private builds and extensions to high rise developments and Motorway Service Areas, working with home owners, architects, developers, retailers 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.

Daylight and Sunlight Assessments

Why the need to assess?

Daylight and Sunlight Assessments can help improve the design of a scheme at all stages in the design process from scoping out development potential and identifying specific site constraints to quantifying daylight and sunlight provision inside new dwellings. The impact of a new development on the daylight and sunlight provision of its surroundings is a material planning consideration.

Ensuring sufficient internal lighting, balancing acceptable impact to neighbours

In line with the recommended methodology set out within the BRE Guidelines, a series of tests is applied to both Daylight and Sunlight Assessments. All our analysis for daylight and sunlight is carried out using a 3D numerical site model of the existing and surrounding buildings. Daylight and sunlight model simulations are undertaken for both the ‘existing’ and ‘with development’ scenarios.

BREAAM: We can undertake Daylight Assessments to meet the BREEAM requirements
for daylight provision within proposed new internal spaces of dwellings.

The impact on neighbouring buildings is assessed with the following tests:

Vertical Sky Component (VSC) – The amount of sky that is visible from each window of the affected building(s)

No Sky Line (NSL) sometimes referred to as Daylight Distribution – Quantifies the impact on the distribution of daylight within the room

Annual Probable Sunlight Hours (APSH) – Quantifies the impact a new development will have on the amount of sunlight available to neighbouring buildings

Sunlight to amenity spaces/overshadowing – Impact will be assessed using the ‘sun hours on the ground’ test carried out on a specific day of the year, as per BRE Guidelines

Overshadowing from tall buildings and at sensitive sites

There is sometimes a requirement to assess overshadowing in greater detail and this is particularly important where tall buildings have the potential to cast far-reaching shadows, or where there are sensitive areas in close proximity to the site. A transient overshadowing study is carried out for a range of dates during the year with shadow positions plotted throughout each day, again with and without the development in place.

What our Clients say

“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.”

Private Client