What a Daylight Assessment Report can do for You

In order to be able to classify a room as ‘habitable’ you need to be able to prove that minimum levels of natural light and ventilation can be achieved.  Habitable rooms are bedrooms, living rooms and kitchens.  The criterion used by UK planning authorities to evaluate the amount of natural light is the Average Daylight Factor (ADF).  The derivation of means of calculating ADF is included with BS 8206 Part 2 Code of Practice for Daylighting, the algorithm for calculating ADF takes into account a wide range of influences and factors.

 “It is considered good practice that rooms in dwellings and most other buildings have a predominantly daylit appearance. In order to achieve this the average daylight factor should not be less than 2.0 %”, BS 8206 – 2 2008 Code of practice for daylighting.

Limitless Ltd has had a comprehensive piece of software developed by the Building Research Establishment (BRE), specifically designed to calculate ADF for our unique Mirror Shaft and Light Shaft systems. This software takes into account the room and window dimensions, the parameters of the Mirror Shaft or Light Shaft, the reflectances of both room and Mirror Shaft/Light Shaft surfaces, the types of glass in the Mirror Shaft and window or in the Light Shaft. Obstructions to light outside the building are also factored into the calculation.

When developing a Daylight Assessment Report we use an external daylight level of 25,000 lux – an overcast but bright day, very typical in the UK.

This DAR can support your planning application or be used when appealing a council decision to prove the amount of daylight a Mirror Shaft or Light Shaft will provide. Rooms designed to comply with the natural daylight standards in BS 8206 Part 2 are pleasant places to live and work.  The difference our system makes is astonishing and extremely impressive.

Natural Light it’s Good For You & Doesn’t Cost The Earth