The proposed model is implemented through the iterative processes shown in Figure 5:11. The implementation process links current design processes with passive design and end user needs. The stages of the process are considered to be vital in linking passive design strategies and end user needs’ aspirations. The process stages are the foundation on which user centred passive building design is implemented. This process is conceived to reflect the special characteristics of building design pro- cesses. The aim of the procedure is to help the designer to consider iteratively the components of the model to ensure that needs of the end users are fulfilled. This process is divided into three main stages as shown in Figure 5:11.
Figure 5:11: User Centred Passive Building Design Process. (Concept stage, R: Requirements and C: Con- text)
5.7.1 Concept and Sketch stage:
The implantation process starts at the concept and sketch stages. The main aim here is to identify the need for using user centred design approach. The designer will work to extract the client aspira- tions and the expected building functional characteristics, life span and in use requirements. Andresen et al (2008) pointed out “architects and engineering provide mutual inspiration in a way that fulfilling the design functions. Gething (2011) suggested that ecological design strategies requirements ought to be elicited at the concept design stage. It is expected that the end users’ needs are established along
with the pattern and performance requirements for passive lighting, ventilation and thermal. The de- signer is expected to consider space layout, plan depths, form, orientation, and other relevant design strategies in relation passive design functional requirements and users aspirations. The designer must keep the end users’ requirements in check in every proposed concept sketches and design solutions.
By doing so it augments the chance of delivering an asset that fulfils end users aspirations. The dif- ferent between the concept stage of the proposed model and other traditional design methods is in the systematic consideration and classification of end user factors to create design solutions that are users’ complaint, durable and resilient to rapid changes.
5.7.2 Design and Development Stage
The design development stage is composed of two steps. These are passive design context and so- lutions generation. In the first stage the main issue that need to be considered here is the translation of the captured information in matrices, concept sketches and other forms to create design technical solutions. Also, it is expected that design specifications and technical details are conceived in relation
to end user needs and other contextual data. It is expected here that a designer will specify a design function then try to check if the specified function concurs with the user expectations. This can achieved through using advanced modelling and simulation to prove the proposed design. In doing so the designer must reconcile between all the conflicts that may exists between function performance and end user attributes. For example, to design a window, a designer should first indentify the func- tional requirements of the space in relation to passive passive lighting, ventilation and heating. Based on the functional requirements and user attributes the designer will identify a suitable strategy that realizes all the preconditions. The process here differs from other design processes through the fact that the five user design attributes are considered in every proposed design solution. Thus the driving theme for deriving design solutions is functionality that responds to end-user design attributes. The derived design solutions, from the previous stage, are subjected to testing against the passive design strategies to ensure that the design performs as perceived as well as satisfies end user aspirations. The selection process is informed by architects’ experience and perception of the real world or usage sce- narios. The design solutions should mainly be selected on functionality and the level of end user factors inclusion in the solutions. It is here where the end user assessments tool can play a major role in indentify solutions that are EUs compliant.
5.7.3 Design Synthesis Stage
This consists of assessment and adoption of the proposed design solutions. Andresen et al (2008) explained “this stage shows the extent to which the design meets owner requirements”. The designer should be experienced enough to evaluate his/her work to insure integration and compliance with end users factors. It is the last possible chance to redesign and rethink the proposed solutions before pro- ducing the working drawings. It is more cost effective to change design at this point than a later stage. The adopted design solution should be subjected to what if analysis scenarios to identify and iron out any performance and end user compliance issues. This assessment should not be limited to present requirements but also future usage scenarios. At the end of the assessment there are three possible outcomes. The first outcome is that the proposed design solution meets EU needs and partially fulfils some of the PD function requirements. Thus the solution needs to be modified to eliminate the inade- quacy in the function. In this scenario, the designer has to go back to the second stage and re-start the design process all over again as explained above. The second possible result is that EU needs and functional requirements are met. Thus, design adopted, and the process completed for the design task in hand. The third outcome, the designer discovers various omissions in relation to end user factors integration and passive design functionality. In this situation the designer has to re-start from the con- cept stage go through the process as described previously.
5.7.4 The Post Evaluation
After all design tasks are completed it is possible to evaluate the whole building for compliance with end-user requirements. This process is similar to certification of the design compliance (similar to BREAM). The main five the end user factor s can be developed as tool to serve this purpose.