Appraising the performance of long span sportshalls and swimming pools in Greece.

V. BOURDAKIS & R.F. FELLOWS

The universal problem of evaluating and assessing appropriateness, effectiveness and the performance of constructional systems and materials used in buildings is addressed in application to long span structures in Greece. In buildings spanning up to 15 metres, in-situ reinforced concrete frames with non-loadbearing brick walls are the dominant constructional system used. Among the reasons for this preference are the low cost of the materials, which are produced locally, and the availability of labour. The lack of tailor-made codes of practice for steel and timber construction in Greece, coupled with architects’ and structural engineers’ lack of knowledge on how to design steel, timber and tension structures, the high cost of imported structural materials and management and operatives’ capabilities are critical issues.

In long spanning buildings (over 25 metres) there is no dominant constructional system or structural material. Various opinions and arguments from architects, building engineers, contractors and theoreticians have led to a long-lasting debate. Amongst the constructional systems argued for and adopted in Greece during the last twenty years are steel space frames, space decks and trusses, tension structures, timber (Glu-lam) beams, fabric tents and prestressed reinforced concrete.

The importance of the debate, together with an increasing need for long spanning buildings to house exhibitions, conference and sports halls, warehouses and swimming pools, forced the Technical Chamber of Greece to hold a Scientific Seminar on Long Span Structures (Technical Chamber of Greece, 1992). The main problems highlighted were the availability and suitability of structural materials, need for new building standards, import of knowhow on a permanent basis, quality control and educational needs of engineers.

Considering the existing needs, future trends, number of buildings built, availability of data and variety of structural systems implemented, this paper focuses on sports halls and swimming pools spanning 25 to 60 metres. Korbas (interview, 1990 - architect, member of the Design Department of the General Sports’ Secretariat - DDGSS), confirmed that the vast majority of such buildings are General Sport Secretariat (GSS) developments. As far as availability of information is concerned, the existence of this public board is critical.

The aim of the paper is to investigate the performance of the various constructional systems used by the GSS for long spanning sports halls and swimming pools in Greece and to devise an objective evaluation method for their assessment. The objectives set were to develop a model for appraising the buildings and to evaluate the performance of a sample of those buildings. The overall research process is shown in Figure 1.

Figure 1 The Research Process

The problem of decision making during building design, in terms of structural materials, subassemblies and constructional systems used, is an enduring one (CIB W60, 1975). This issue is closely related to the evaluation of building elements in order to identify their properties and, subsequently, their applicability for particular needs. The same problem exists as far as evaluation in use is concerned; according to Shibley (1982) ‘Buildings need constant adjustments to the needs of their users’, which leads to a requirement for continuous assessment, evaluation and fine tuning of the building objectives, following users’ feedback—feed forward, in Markus’s (1972) terminology.

Building performance has been investigated and researched considerably—especially during the 1960’s and 1970’s. W60 (1975), commissioned by the CIB on the performance concept, stated that: ‘As a term to characterize the fact that products must have certain properties to enable them to function when exposed to stresses, the word performance has been chosen. Use of the performance concept implies an attempt to define how a result aimed at should be able to perform—without resorting to a description of what the result should be’. Preiser et al (1988) note that: ‘in the performance concept, the behaviours, qualities and accomplishments of people and things are measured and evaluated’.

There are three main categories of studies of buildings’ performances. The performance concept itself - in terms of identifying problems, investigating and setting performance requirements, criteria and performance specifications for particular building types. The evaluation of buildings in the design stage - employing the performance concept as a tool for analysis and evaluation of proposed solutions. The appraisal of buildings in use - evaluating existing buildings.

‘Appraisal is the process by which completed buildings are assessed, judged or evaluated by the client, the users (if distinct from the client), the designers or by a combination of any of these, it is about testing whether the designers priorities (objectives) are reflected successfully in the building and about whether the designer’s priorities were right in the first place’ (Bishop, 1978, emphasis added). Manning (1987) suggests that many appraisals provide specific knowledge of the performance of individual aspects of particular buildings. Hence, the objective of appraisals are to add to the body of knowledge concerning the performance of completed buildings so as to inform future designers of the likely performance consequences of design decisions.

The concept of appraisal, as analysed by the Building Performance Research Unit (BPRU, Markus et al, 1972), is related to the establishment of the quality or performance of a solution and incorporates three basic steps:

1. ‘Representation in which the solution is modelled in a suitable way. This representation may be verbal, mathematical, visual or even full–scale (a building in use is a full model).
2. Measurement where the performance of the model is obtained on as wide a variety of counts as necessary.
3. Evaluation, when the measured results are processed.’

Clearly, a significant issue in the appraisal of buildings is the determination of the performance criteria against which the appraisal will occur. Two further facets merit consideration, applicable parameters (which constrain potential performance) and the human aspects of the appraisal process - the identities of appraiser and appraisee and the perspectives adopted (independent of the appraisal techniques). The experiences of the individuals concerned impacts on the appraisals also (for a discussion and explication, see Liu, 1995).

Project participants each have goals which impact on the project through interpretation and fulfilment of performance. Hence, the individual goals of project participants are likely to modify goals determined for the project, if only in the realisation of the project goals. Thus, a hierarchy of goals is applicable and the primary participants - usually the client and close advisors - determine the goals to be applied to the project - their identity and relative importances. Commonly, expression of such goals to project participants is poor with the result the goals are assumed and performance proceeds accordingly with individual participants’ seeking to secure bounded benefits to themselves. For GSS projects, the presence of known goals is a notable advantage and facilitates appraisals to be carried out against expressed criteria.

During the late 1970’s, post–occupancy evaluations (POE) were developed, notably in USA. Preiser et al (1988), emphasise that the philosophical and theoretical foundation of POE is the performance concept: ‘POE is an appraisal of the degree to which a designed setting satisfies and supports explicit and implicit human needs and values of those for whom a building is designed’. In their more rigorous forms, POEs follow a systematic approach where all user groups are represented and all important design elements are examined. Figure 2 illustrates the relationship between performance, POE and the development and use of a building.

Figure 2 Building Appraisal Methodologies Implemented

The approaches followed in the methodologies for appraisal of buildings can be classified as; theoretical and practical (figure 2). Theoretical, partial approaches rigorously examine a narrow section of buildings’ performance. Theoretical, inclusive approaches analyse all aspects and present a holistic view. The majority of theoretical approaches are of the framework type, identifying some variables and measuring each one individually (partial). Consequently, they do not develop an overall measure of building performance or a model for the quantification of the results. A particular issue is that of aggregating the components of the appraisal - the performance of the whole building in context is not necessarily the arithmetic sum of the individual components - consideration must be given to component weightings and to potential synergy together with the appraisal mechanism and the participation of appraiser and appraisee.

However, certain approaches do develop models for appraising buildings; BPRU is one of the more widely known. The BPRU model is inclusive and, although focusing on school buildings, the team that developed this model argue that it can be modified and applied to a wide variety of building types. The important characteristic of the model is that the building is divided in four sub–systems (building, environmental, activity–behaviour and organisational); a measure of cost is related to each sub–system. Consequently, all four sub-systems are interrelated and examined as totalities, facilitating the drawing of inclusive conclusions.

The criteria set and the models developed in practical approaches are suitable for specific building types only. As these, mostly, are conducted by public sector departments, the criteria are related to the use, function and maintenance costs. These are more technically oriented than the theoretical, inclusive approaches.

Crise (1975) developed a model for the assessment of expected performance effectiveness. This model focuses on industrialised buildings and examines them in terms of technological and economic performance. It is not an inclusive model since sociological, psychological and environmental issues are not considered: The model is applied in the pre-selection stage, assessing various alternatives. An explicit classification of techno-economical variables is presented in three levels and, following the calculation of the relative effectiveness indices for the two first levels, the overall effectiveness index of each industrialised building is calculated.

Manning (1987) argues that there seems to be no mechanism through which the conclusions of an appraisal of one building can be applied to other buildings, probably due to the individual ‘technical’ facets of buildings (even those of the same type etc.) and the particular criteria of individual clients and other project participants in setting the goals against which appraisals should be executed. Manning’s view is in contrast to the belief that appraisals should (and can) enlighten and improve the (generic) design process; existing methods of appraisal provide only specific knowledge of performances of particular aspects of particular buildings.

Boyd et al (1988) note that appraisals tend to be invasive, expensive and time-consuming, exacerbated by the beneficiaries of the appraisals being other than those who bear the costs of the appraisals’ executions. Manning (1987) comments, ‘…the quality and authority of an evaluation is influenced by the amount of time, the depth and amount of professional or research competence and experience that is committed to the task’.

A general typology for factors relating to the appraisal of buildings is Technical, Functional and Behavioural. The building, its environment and uses should be considered in the context of historic and design forces which shaped the provision to properly inform input into future designs (Friedmann et al, 1978). The theoretical approaches, which focus on methodologies and tests to yield frameworks and models for appraisals, are essential in informing practical appraisals.

The GSSmodel is based on the evaluation of proposals submitted by contracting firms; usually projects are Design and Build. The evaluation considers the quantitative variable of the contractor’s bid sum and the qualitative variable of the proposed plan's likely performance. The evaluating committee first examines the proposals' performances and then evaluates them against a number of criteria. Failure of a proposal to meet a criterion within the accepted limits set in the brief leads to disqualification as unacceptable. Finally, by adding the marks gained against each criterion, each proposal is awarded an overall mark—the total grading. Next, the sealed contractor’s bid sum is opened and the real offer of the competitor is calculated by the formula:

Contractor’s Real Offer =

leading to the determination of the best value bidder, the contractor with the lowest ‘real offer’.

Thus, the GSS model contains two main variables; cost and quality. The cost variable includes the net building costs (incorporating all construction-related costs, such as structural material costs, labour and plant costs), the general costs (undertaking and presenting the design and construction plans, working details, building permit expenses, protection and safety measures etc.) and the revision and unexpected costs (relating to possible alterations and changes in the initial design as well as inflation compensation). Quality incorporates eleven parameters: (see Table1) aesthetics (external and internal appearance of the building), function (of the building in general, in relation to its use(s) and to its surrounding environment), loadbearing structure (overall arrangement, combination of the loadbearing and non-loadbearing members of the building and durability), lighting of the main hall, heating, plant room, machinery and e/m equipment, building materials and their specifications, energy conservation systems (passive energy, etc), acoustics of the main hall and repairs and maintenance (simplicity, flexibility and economy in repairing and maintaining the building).

Although the times for design and for construction are noted, the GSS model assesses the time variable indirectly against cost by imposing charges for any delays occurring in design completion (submission of the final construction plans and details) and overall completion deadline (construction completion to handover). These charges are daily and are expressed as a percentage of the mean daily cost of the building. The latter is calculated by dividing the contractor’s bid sum by the contract period specified by GSS for the completion (this period is in calendar, not working, days). The maximum delay accepted by the GSS for the construction period is 30% over the period specified in the contract. If this is exceeded, employment of the contractor may be determined.

According to the SSBRT (1976) framework, building performance is assessed under five systems: environmental, activities, technical, costs–resources, cultural–symbolic. Subsequently, the effects of constructional system changes on the environment, the activities, the resources and culture are examined to produce an overall measure of building performance.

Following a classification of the sports hall and swimming pool buildings, in-use evaluation of ten buildings was conducted. A model was constructed aiming at an overall measurement of building performance and facilitating comparisons between buildings of different constructional systems.

In order to obtain a complete analysis of the independent variables and their relative importance, evaluation of the quality parameters is needed. The GSS model incorporates a chart assigning grading values to all eleven parameters. As each parameter is of varying importance, the maximum and minimum gradings differ. Analysis of the GSS variables and weightings yields Table 1.

Table 1 Weighting of the Quality Parameters

In Table 1 the GSS grading, as a reference point, is in the first column showing how GSS conceives the relative importance of the parameters. As a maximum and a minimum grading is stated, the mean grade value is calculated (second column) to facilitate relating the parameters in single numbers (rather than ranges). The third column shows the relative importance of these eleven parameters calculated through the mean GSS gradings.

In order to have an inclusive view and to assess the GSS model at a holistic level, the relative importance of the three main dependent variables are calculated by examining them in pairs. Cost – quality and, cost – time are calculated; the third, quality – time is derived from the relationships of the other two pairs.

The first pair (following calculations–Bourdakis, 1994 - using the weighting of the components of the GSS model) yields . This means that the cost–quality ratio is 1:1.28. Similarly, (Bourdakis, 1994) the daily delay is charged with 0.1 of the daily cost, leading to a cost time relation of 10 to 1.

Hence, for the GSS standard model for assessment of contractors’ bids (and Design and Build proposals) cost has a weight of 42% of the total, quality counts for 53.8% and time is 4.2% (due to the rarity of overruns; the construction duration is specified).

The model of appraisal which has been developed has the GSS model as its starting point. The constructional system performance appraisal variables are classified under three headings.

1. Resources, is similar to the resources modifier noted by Hillier et al (1972) and SSBRT’s (1976) cost–resources. This variable incorporates two of the three main variables of the GSS model: cost and time. These are examined in the provision level (as in construction costs and time spent of the GSS model) and in–use (HVAC costs, energy conservation and maintenance).
2. Human–user satisfaction, includes the physical environment, as discussed in Markus’s (1972) environmental system: "...aspects of the environmental system directly perceived as heat, light, sound, texture and smell," and psychological faactors. Psychological factors are presented in Zunde’s (1982) analysis under delight, visual aesthetics and in Preiser's et al (1988) behavioural elements of post–occupancy evaluation. Essentially, physical environment deals with heating, lighting and acoustics, whereas psychological factors concern aesthetics and spatial configuration.
3. Technical variable is identical to the SSBRT (1976) technical category and resembles Preiser’s et al (1988) category, where structural integrity, durability and general performance of the various building systems is assessed, and the BPRU (1972) building system. However, only two out of BPRU's three sub–systems are examined; constructional and services; contents are excluded. The technical variable is divided in two, building structure and maintenance. Building structure is assessed in terms of the GSS model parameters of origin of building materials and complexity and prefabrication of the building envelope; maintenance is examined as in the GSS analysis (availability of spares and cost of repairs).

Table 2 presents the three main variables, the aspects considered in each and the relevant GSS parameters.

Table 2 Main Variables for the Constructional System Performance Appraisal

Resources is the only purely quantitative variable, incorporating cost and time dependent parameters. In order to measure sports halls’ and swimming pools’ cost performance, the total cost of each building is calculated. The components of the total cost examined for the life span of a building are the capital and running costs only (Figure 3). Capital costs include the construction costs and professional fees, expressed through the sum of envelope and services construction costs minus the construction delay fines (if any).

Figure 3 Analysis of the Cost Variable

The running costs are divided into annual and periodic. Annual costs include maintenance, operating services and energy (Lee, 1983). Maintenance is defined as ‘a combination of any actions carried out to retain an item in, or restore it to, an acceptable condition’ (BS3811:1964) and, therefore, deals with the cost of spares, labour etc. involved in the "preventive" as well as "corrective" maintenance of the buildings. Operating services—as a "base cost" of using the building (not part of the occupancy costs)—are measured through the annual salaries of the personnel and the annual costs of consumables. Energy comprises electricity (lighting, ventilating, air–conditioning etc.) and oil (all buildings examined use oil for heating) annual costs.

Two further issues in the annual cost analysis model are the daily hours of use and the annual duration of maintenance (when the building is not available to the users; the buildings are shut only for maintenance work and not for summer or other types of vacation, the former affects the operation, energy and maintenance costs whereas the latter affects the energy costs only). Additionally, all cost measures need adjustment for the size of each building (normalised) by dividing them by the usable building area. Inclusion of all the annual cost and use factors yeilds the following formula:

(drx/m²)

Periodic costs—such as electro mechanical installations’ refurbishment and/or replacement; envelope members’ replacement—are maintenance-related actions taken at intervals greater than one year.

Time measures of the building’s performance are assessed through the construction delays’ fines, the annual maintenance duration and the intervals between the periodic maintenance (bearing in mind that the intervals vary in regard to the particular assembly). The in–use indicators are calculated annually. The analysis is summarised in Table 3.

Table 3 Resources Indicators

Human–user satisfaction, is a qualitative variable assessed through psychological and physical environment indicators. These indicators are classified in five categories: aesthetics, HVAC, lighting, acoustics and functionality. The environment–activity interaction parameters are measured through the users' opinions, whereas physical environment indicators are assessed by the researcher - a qualified architect conducting a common-level assessment (see Table 4). The main source of information is the users—assessment of the physical indicators supplement the analysis, facilitating a holistic view of the existing conditions and of the specific data collection day (temperature, physical phenomena occurred, etc.).

Table 4 Human–User Satisfaction Indicators

Aesthetics are measured via users’ opinions of the appeal of the building as a whole and of the hall alone. The relevant physical indicators are the shape and size of elevations, colours used and main hall’s properties. The researcher’s observations are noted in supplement and to provide common assessment across the sample of buildings.

In terms of HVAC, users’ opinions of heating, comfort, air quality and ventilation are monitored. Additionally, the physical indicators of temperature influencors (proximity to the sea, open space or protected by buildings, strong winds, etc.), air quality (dust, pollution) and condensation are considered.

Users’ perceptions of lighting issues, notably daylight intensity and glare problems are obtained. The physical indicators - the window area, texture and orientation and the properties (colour, texture etc.) of the hall’s walls - are assessed from inspection of the buildings and drawings. Additionally, the buildings’ managements provide objective information on how often (if at all) artificial lighting is used during day time—what time of the day the lighting is turned on for a set week of the year (to facilitate comparisons).

Acoustics, and noise penetration from the surrounding environment, are considered through users’ opinions. The environment, in terms of noise sources that are potential causes of disturbance (traffic load, factories etc.), are the physical indicators investigated by the researcher.

In terms of functionality, users are questioned on the perceived safety of the buildings and the visibility lines from the seating area. The researcher observed the whole building in order to identify areas of potential problems (such as walls’ protrusions).

In assessing the Technical variable, unlike the GSS analysis which considers the loadbearing structure, building materials and maintenance, this study focuses on the building envelope, using the indicators of; industrialisation of the building envelope, origin of the structural materials, construction complexity and availability of spares (see Table 5). Cost related functions are developed for the measurement of the first two indicators, whereas the remaining two are measured by questioning the building supervisors assigned by the GSS during the construction.

, (%)

, (%)

Table 5 Technical Indicators

The relative importance of each main variable must be established to facilitate accurate evaluation of the performance of each constructional system. However, such evaluation creates a problem as two major sources of information for the weightings exist - the GSS and the opinion of Greek architects and engineers who design sports halls and swimming pools. Hence, two sets of weightings, one according to the GSS and another according to the architects and engineers, are compared.

Semi-structured interviews with a small sample of building professionals were conducted in Greece during the pilot study. In these interviews, the researcher introduced the three main variables, the practitioners were asked to comment on the GSS weighting and, finally, to suggest their own weightings. The engineers questioned were selected from GSS so that they represent a wide age group with various qualifications and specialisations. A University lecturer in building engineering (35 years experience) was questioned too. Further, a relatively inexperienced architect was included as well as a very experienced GSS architect and another of 10 years experience plus the researcher’s opinion (as an independent architect).

The percentages derived from the GSS analysis are:

Resources= 42 + 4.2 + 3 + 1.9 + 1.6 = 52.7

(cost, time, maintenance (part), energy conservation and heating (part)).

Human-User Satisfaction= 8.4 + 5 + 2.5 + 2 + 3 + 2.3 = 23.2

(aesthetics, function (part), lighting, heating (part), machinery & equipment (part) and acoustics).

Technical= 8.4 + 3.4 + 1.5 = 13.3

(loadbearing structure, building materials and maintenance (part)). Normalising the weighting to sum to 100: Resources = 59%; Human-User Satisfaction = 26%; Technical = 15%.

The percentages derived from the interviews of Greek building professionals are Resources = 42.3%; Human–User Satisfaction = 32%; Technical = 25.7% ( Table 6). The practitioners emphasise technical and human-user satisfaction to a greater extent than does GSS.

Table 6 Relative Importance of the Research Variables

Having established the co–efficients for each main variable and of their component indicators, the relationship between the performance levels of human-user satisfaction, resources and technical must be established.

Each building is examined at three levels, overall, research related and envelope only. Information is gathered from all four stages of the building life; briefing, construction design, construction and in–use. The buildings are appraised by collecting information from the users, neighbours, building management team, construction supervisors, architects, engineers and clients in order that a comprehensive perspective is secured.

Multiple case studies were conducted on a sample of buildings in Greece following classification of the sportshall and swimming pool buildings. This method combines the advantages of case studies (depth of research) and surveys (breadth), is flexible and likely to reach reliable conclusions (Yin, 1989). The sample includes the various constructional systems used (steel trusses and spaceframes, glue laminated, tents, reinforced concrete), represented proportionally. The ages of the buildings selected are such that the maintenance and service histories are available and accessible. Table 7 presents the buildings analysed. A pair of identical buildings is included in the sample to facilitate assessment and testing of the research methodology by examining and calculating the significance of variation among the ‘paired’ buildings.

Table 7 Research's Building Sample

Findings

A timber Glu-lam framed sportshall (Loutraki) was the overall best-performing building. Good long term performance of the Loutraki sports hall was predicted by reference to the running and maintenance costs as well as HUS performance of the similar structured, but much older, Galatsi sportshall. Generally, Glu-lam proves to be better than the alternative constructional systems examined in terms of overall performance.

Steel space framed buildings (as featured in Peristeri and Arta) have quite poor performances due to their high capital costs and technical complexity leading to expensive servicing. The flat roofs that such constructions employ constitute another source of problems.

Conversely, steel trussed frames—as in the form employed in Rethymno—are very close to timber in overall performance. This is due to the improved structural details implemented in terms of roof cladding, steel frame, wall panels insulation and windows.

The tents examined are subdivided into two categories; the old (over 7 years) tents supported by a steel structural frame and the tensioned fabric tents. The quality and HUS performance of the older examples (Patra and Posidonio) analysed, approximately eight years after their construction, is very poor. Their advantages are the extensive prefabrication leading to fast erection and the low capital cost; such factors alone are not sufficient to make a building successful.

The analysis of the HUS performance figures of the latest tent–structured example (Hios double skin tent), demonstrates that this constructional system is highly competitive, rated third in both HUS performance and overall.

Passive energy systems were applied in only two out of the ten buildings of the sample. Substantial reduction in energy expenses (up to 40% of the annual heating oil consumption) was measured in both Loutraki and Hios buildings due to implementation of solar collectors and use of hot water from a neighbouring power station respectively. The serious problems that occurred (roofs' waterproofing failures, pipes' insulation, protection against frost, etc.) in a few older examples, where solar collectors were used (Hatzakou, interview 1991), has made DDGSS reluctant on their use. This is reflected in the low relative importance of this issue in the GSS model for evaluation of proposals.

North lighting and rooflights scored high in users' and athletes' opinions due to absence of reflections and glare whist producing constancy in the light intensity. The field work revealed that, in terms of natural lighting, most buildings featured windows oriented to the east, south and west; these proved distracting and annoying to users, both athletes and spectators. Such provision of windows is caused by the GSS briefs specifying the total area of windows to be at least 25% of the hall’s floor area, whilst not prescribing on the orientation of the windows. In order to avoid disqualification by the judging committee, designers must include the specified amount of windows even if some windows must occur in inappropriate locations. Designers prefer to specify windows rather than rooflights as the latter are more difficult to design and construct and impose extra waterproofing problems.

The constructional systems implemented in the last five years show a great improvement over older systems in terms of overall performance rating. The main reasons are the design improvements, the constructional details used, lower running costs, improved heating, aesthetics and lighting. All three constructional systems (based on timber glue laminated, steel trusses and tents) have similar performance and, therefore, are appropriate in Greece. However, the particularities of their implementation (such as cladding, lighting, heating, energy conservation, colours etc.) are key issues in constructing well performing buildings.

Performance comparisons between constructional systems used in swimming pools and sportshalls should be made with much care as both capital and running costs are affected by the function of the buildings’ leading to higher figures for the pools. Similarly, great care must be taken in interpreting and generalising conclusions drawn on particular constructional systems since performance is related to non–structural as well as structural issues.

Spans in the region of 40 metres cannot be covered using simple reinforced concrete structures. Therefore, imported prestressed concrete technology is required with the consequent serious drawback in terms of roofing capital costs. Such spans make the capital cost involved non-competitive—up to 30% (in drx/m2) higher than Glu-lam timber, steel trusses and tents. Consequently, concrete based structures, including prestressed ones, are not financially efficient solutions for Greece. However, all constructional systems reviewed use reinforced concrete in the substructure and, in many buildings, up to the roof level and perimetric beam (all steel framed examples).

Spectators’ opinion on lighting, especially for tents, is forgiving whereas athletes are very strict in their judgement. The variation in results is due to users’ horizontal and upward directions of viewing, while spectators watch mainly on the horizontal plane and downwards. Artificial lighting is a cause of problems in the ‘budget’ halls. The incandescent bulbs and fluorescent tubes used result in higher running costs and extensive criticism from users. Systems like the quartz–iodine tungsten filament lamps (suggested by Traister, 1982, used in Peristeri as the only source of lighting, and Loutraki) led to top HUS lighting performance sampled. Tents’ lighting performance is dependent on the transparency of the fabric cover. Extreme conditions (very transparent and very dark fabrics) are criticised extensively by both users and athletes.

Analysis of performance of the buildings in respect of aesthetics and acoustics shows that constructions featuring reinforced concrete are preferred by both users and spectators. The properties and similarity of concrete structures to the everyday architecture which users in Greece encounter (notably stone masonry), is a major factor in this preference.

The main issues that an inclusive building appraisal model should address are cost, time, users' satisfaction and technical. The research model which has been developed, uses data obtained from the methodologies presented and discussed in the literature as well as from the GSS model. Cost and time, grouped together as resources, is the parameter of major importance in the last decade. The life cycle cost approach encourages comprehensive financial modelling of the buildings under evaluation.

Users' satisfaction is the second most important issue according to both the GSS model and the survey of building professionals. Technical facets facilitate the development of objective measures addressing HVAC, constructional details, materials used, acoustics, electromechanical installations, passive energy systems etc.

Most building appraisal methods end at the level of data analysis and draw conclusions on individual aspects thereby, focusing on a fraction of the problem of building appraisal. Hence, the holistic building appraisal model developed is of importance (as it is both quantified and comprehensive).