Figure 3.1 Interrelation of buildings` design criteria

In order to meet the forementioned demands, there are two types of design principles, measures and systems which can be used, such as: passive and activesystems.

Passive systems take advantage of natural energy flows, such as the solar and wind energy to regulate the buildings` heating, cooling, daylighting and ventilation demand. Sustainable design that utilizes the local microclimate could lead to up to a 60% reduction of the energy demand. The use of passive heating, passive cooling and daylighting can reduce the energy demand by a another 20%, amounting to 50-80% reduction[38].

Active systems require additional energy for their for operation, as they are mechanical, electrical systems and appliances. In order to have a net-zero building or plus-energy building which produces more energy than its needs, highly efficient active technologies should be used. In building design, passive technologies should predominate over active ones.

Figure 3.1Interrelation of buildings` design criteria

Considering the complex and multidisciplinary nature of the sustainability it is necessary to look upon the significance on each design criteria separately in the context of the buildings. Also, all of the design criteria are somewhat interdependent and influence each other. The buildings orientation, form and functional layout can influence the energy performance, daylight quality, construction costs etc. The choice of the materials can influence the buildings` embodied carbon, energy performance, comfort (thermal, acoustic etc.), costs, dimensioning of the mechanical systems etc. In such a complex system of many design criteria it is required to use multi-criteria assessment to inform the architectural design decisions.