MCA Post Occupancy Evaluation

The most common POE methods can be divided into two categories: subjective methods and objective measurements.

Subjective methods:

• Surveys: on occupant satisfaction, thermal comfort, visual comfort and other customised surveys.
• Interviews: structured or semi-structured interviews, meetings and workshops with occupants and experts.
• Inspections by experts to identify problems through photographic documentation.

Objective measurements:

• Measurements of indoor environmental quality (IEQ): thermal conditions, lighting, air quantity and acoustics.
• Measurements of energy consumption: energy consumed is assessed through audits, sensors or utility bills.
• Measurements of water demand: evaluated via utility bills.

Generally speaking, subjective methods are used the most because they are the cheapest and help to identify problems easily. In particular, surveys are the most widely used method because they make it possible to quantify subjective data through questionnaires and compare the results. The fact that user feedback has become the main focus of POEs reflects how the success of a building is primarily determined by the level of satisfaction of those who occupy and use the space.

Within the MCA environment, it is proposed: the dissemination of a questionnaire among users, the analysis of energy consumption, the direct observation of the building and proposed strategies of implementation.

These simple activities make it possible to understand the occupants’ level of satisfaction with the building, how they evaluate it in its different parts and according to different criteria, and which elements most influence comfort, consumption, and environmental impact.

The questionnaire is divided into questions relating to the type of user and their use of the workspace, thermal, visual and acoustic comfort, travel and eating habits during office hours. Once the answers have been collected and statistics have been drawn up, the qualitative and a posteriori analysis of the spaces, by studying the descriptive drawings of the building and direct observation of the rooms, allows initial considerations to be drawn concerning possible causes, to optimise the quantitative analyses to be carried out later.

The information gathered through qualitative analysis provides support for the quantitative phase. This involves:

• the performance of on-site measurements;
• the elaboration of environmental simulations;
• the analysis of consumption accounted for and estimated.

During summer period, the measurements were carried out through: data loggers that are installed at significant points in the building (defined based on the findings of the qualitative analysis carried out previously) and that allows a profile of temperature and humidity to be traced for a typical week, including weekends; specific instrumentation that allow the illuminance on the working surfaces and the surface temperature to be measured at specific times of the day and under different conditions. Simulations will be done in winter too.

The consumption analysis is carried out by collecting consumption information (bills), analysing the charging cycles of some significant supplies (e.g. paper, water, etc.), in agreement with the Office Manager, and identifying a standard period.

Thanks to the constant monitoring of the situation and the various parameters considered, it was possible to outline the environmental behaviour of the office. On one hand, these results help to understand “where we are” concerning the various environmental standards and benchmarks and on the other hand they help to draw up a series of implementation strategies to be carried out both at the company level and also in everyday life by all users.

The results showed that it is possible to control and minimise the use of air conditioning systems and favour passive strategies that allow a considerable reduction in consumption. It is also important to the topic of daylighting, for which the orientation of the building, the position of the skylights and the presence and possibility of using and modifying the shading systems, allow users to experience the best possible working experience with the possibility of being able to considerably reduce lighting costs.

All the considerations and data collected during the post-occupancy assessment analysis of the offices made it possible to draw up implementation strategies to bring the working experience to a higher level of comfort and significantly reduce consumption and the resulting impact on the environment. Targets for improvement are therefore identified, according to increasing levels, in terms of reducing consumption and improving comfort, and possible alternatives are proposed to pursue these performance gains, to be conveyed not only through a corporate strategy but also through user empowerment and involvement.