Passive design aims to optimise the building form, orientation, fa├žade design and space planning together with overall site layout use to make maximum use of the natural environment in order to provide occupant comfort with minimum use of energy and mechanical systems. In particular it is concerned with:

  • Control of solar heat gains, which can be useful, but which can also cause overheating;
  • Maximising the use of natural daylight, which may favour north lit classrooms;
  • Where appropriate to use natural ventilation, but bearing in mind that mechanical ventilation may offer a more effective and energy efficient solution for highly occupied spaces, such as classrooms;
  • Using thermal mass to stabilise internal temperatures, for example, to reduce the impact of high heat gains and avoid summertime overheating.

It is not possible to provide all the heating, cooling, lighting and ventilation requirements from passive means and therefore some active systems are required. Sustainable design is concerned with maximising the passive aspects of a building and then providing the active parts in the most energy efficient way and wherever possible using low to zero carbon options.

What should I do?

When dealing with the designers make sure they are considering your site's climate conditions. This can have a significant impact on early stage design decisions.

WLGA - CLILC Llywodraeth Cynulliad Cymru / Welsh Assembly Government