Towards a Sustainability Assessment of Hospital Buildings in Flanders: Development of a Life Cycle Environmental and Economic Impact Assessment Tool

Over the past decade, the interest in how hospital buildings are designed and operated has considerably increased. With the urge to decrease the negative impacts of the building stock around the world, hospitals are equally called upon to respond to this matter. As hospital buildings are very complex and, in most cases, also large-scale buildings (in terms of large buildings or clustering of several buildings), it is a real challenge to assess their sustainability. Besides the difficulty to inventory all flows during the life cycle phases, there are also many health and safety requirements which need to be fulfilled and hence require specific design guidelines. These facts can pose significant obstacles to implement sustainability protocols, and a detailed analysis is therefore required to investigate the opportunities for improvement. Tracking the environmental impacts and financial implications of a hospital building from the early design phase onwards enlarges the challenge. This stems from the fact that in order to make accurate assessments and inform a designer on where improvements are possible right from the very first building sketch, a lot of detailed data is necessary which are often lacking at this phase in the design process. Supporting tools or evaluative frameworks for such assessments at the early design phase of hospital building projects are, however lacking to date. The main goal of this research is to provide architects and engineers (of VK Architects & Engineers company) with a design support tool that will help them assess the sustainability of hospital building projects in Flanders during the early design phase. The tool developed in this research is based on an integrated life cycle approach, combining the life cycle assessment and life cycle costing methodologies to assess the environmental and economic performances of general hospital buildings from the early design phase. The design support tool is based on two existing methods developed for buildings in the Belgian context, SuFiQuaD ("Sustainability, Financial and Quality evaluation of Dwelling Types") and MMG ("Environmental profile of building elements"). The complexity of the hospital building is dealt with through the implementation of the "element method for cost control" which uses a hierarchic subdivision of a building into smaller entities (foundations, external walls, floors, installations, etc.). This hierarchical structure is found useful in the context of rough LCA and LCC studies and allows their application during various stages of the design. Furthermore, the tool offers a possibility of comparison between five different hospital typologies, namely linked pavilion, monoblock, podium with one tower, podium with two or more towers and atrium. The calculation of the environmental impacts and financial costs of the selected hospital type is based on a simplified geometry for each of them. The database of building components integrated into the tool was mostly based on the elements found in the case study of Sint-Maarten hospital where a screening LCA and LCC was applied in order to gain insights into the life cycle environmental impacts and financial costs of hospital buildings in Flanders. Elaborating the database included revision of several VK Architects & Engineers' projects for general hospitals and modelling the additional different building elements to include these in the tool. The tool demonstrated major hotspots in terms of environmental impacts and financial costs of general hospital buildings, namely the electricity use for appliances, the energy for heating and hot water production, the cleaning processes and the material production. As hygiene and patient safety will always prevail over other preconditions, mitigating the cleaning processes will be hard. However, improving the high impacts coming from the energy and electricity use seems more feasible. Therefore, an approach is proposed to calculate the operational energy for spatial heating and hot water production during the sketch design of a hospital building using the existing 3D computer-aided design application software available in the company (Rhinoceros 6). The approach delivers estimations on the energy consumption depending on the hospital building geometry and the medical departments required in the competition documents. As the current approach only includes the calculation of the operational energy for spatial heating and hot water production, further steps are necessary to estimate the energy for ventilation, lighting and medical apparatus during the competition phase. Nevertheless, the presented approach was found appropriate and is used as such for communicating the energy use estimation in the developed tool. Architects from VK Architects & Engineers validated the tool during several competitions in which the company participated. The use of the tool has proven its user-friendliness and efficiency in quick calculations of environmental and economic impacts of general hospital buildings. The tool also fulfilled its role in being intuitive to use during the early design phase and served to raise the architect's consciousness regarding his/her design decisions. Moreover, the tool served as a "connector" between architect and engineer, provoking multidisciplinary consultations and brainstorming during the hospital building sketch design. Nevertheless, the tool is subject to several limitations. First of all, the tool is developed for a specific company, and it is only limited to the assessment of environmental and financial performances of hospital buildings, excluding therefore the analysis of the social performance of hospital buildings. Secondly, the building element database in the tool does not yet include the technical installations for heating, cooling and ventilation typically used in hospitals. Thirdly, the simplification of the five hospital typologies results in a very rigid representation of building geometries. This also has an impact on the quantity calculations for certain building elements, namely foundations, pile foundations, loadbearing and non-loadbearing internal walls, stairs, free-standing columns, doors, elevators and electricity cables. Finally, through the use of the tool, it is not yet possible to compare the results obtained with a benchmark building as there is a lack of studies applying LCA and LCC to hospital buildings.

Jaar van publicatie:2019

Toegankelijkheid:Closed