This Solar Design Guide has been produced by Etude and Levitt Bernstein on behalf of Essex County Council, to give developers, architects and homeowners an easy-to-use guide, laying out the key considerations for good solar design. The core principles of good solar design are to balance the needs of  daylighting, useful solar gain and mitigating overheating:

Daylight

Daylight provision is important for buildings. We need daylight to see what we are doing, to give a connection with the outdoors and it can save energy, by reducing reliance on artificial lighting. However, too much daylight can also be a bad thing. Glare is bad for our eyes and can cause headaches and nausea, so careful design is important.

Useful solar gain

Solar heat gain from the sun can be useful. In winter months, useful solar gains can be used to offset the need for heating.

Too much solar gain

If we have too much solar gain there is an increased the risk of overheating. Climate change is already bringing warmer summers with more extreme temperature highs.  With this, overheating in buildings is becoming an increasing threat to occupants’ health and wellbeing, particularly for vulnerable people. In future years, this is set to become even more of an issue. All projects should prioritise natural methods of reducing overheating, over energy-intensive technology like air conditioning. The key steps are to reduce solar gains and maximise ventilation.

Definitions 

• Sunlight is a term used to describe all light coming from the sun. It is made up of infrared, visible, and ultraviolet light. The term is typically used in this guide when assessing external spaces.
• Daylight is the light we need to be able to see (visible light). It can be either direct or diffuse (meaning indirect). North facing rooms can still achieve good daylight levels due to diffuse light.
• Solar gain is short wave radiation from the sun. When it passes through glazing, some of the energy is converted into long-wave radiation (heat). Solar gain is predominantly direct. North facing rooms will usually have low levels of solar gain.