Construction is the industry that has the largest impact on nature and the environment. It often has injurious effects upon nature, which could with reasonable action be minimized. On the other hand, construction technology can also be used to remedy the environment and to help it return to its natural state. The most significant quantifiable environmental impact of the building sector is emissions due to energy consumption. Construction, material manufacturing, and use of buildings are responsible for almost half of the total energy consumption.
Construction is an old and practice-oriented discipline that can be characterized by one-off designs, temporary project organizations, and intensive site operations. The challenges are to produce, operate, and maintain a built environment that meets the needs of its changing owners and users. A new actor that has recently joined the team of customers is the environment. This means that the impacts to resource depletion, harmful emissions, and maintaining biodiversity over the life span of facilities are requested. The main answers are to minimize the use of (nonrenewable) energy sources and to look for adaptability and long service life with good indoor conditions. The current problem is that the clients don't have the tools to set environmental objectives and to manage how they are met in design, construction, operation, disassembly, and disposal.
One approach on the way toward sustainable building is to apply methods and tools to support achieving sustainability. One such attempt is a performance-based requirements management tool for clients in the building process. It provides an approach and method to document performance requirements over the life cycle of buildings. It is based on a generic classification of building properties. The tool includes building type-related reference data on requirements and information concerning relevant verification methods. It is used to form a design brief. The designers' expertise is needed to make designs that meet these objectives.
The approach brings together the objectives of the owner, user, and the society. Different building types and different kinds of projects can be carried out using the same procedure. Environmental issues (indoor conditions, service life, adaptability, environmental burdens, etc.) are considered like other properties (e.g., safety or costs).
Construction and Environment
The most significant quantifiable impact of the building sector is emissions due to energy consumption. In Finland the sector is responsible for almost half of the nation's energy consumption (VTT Building Technology, 1998). The other environmental concerns of our society relate to the environmental burdens of the industry and environmental impacts of traffic. Additional important building-related challenges deal with the service life of building systems and products, maintenance of the existing building stock, and management of the indoor air quality.
Sustainable development has, besides ecological issues, also social and cultural dimensions (Bourdeau et al., 1998). Aiming toward a sustainable built environment requires a paradigm shift where new objectives, in addition to the present ones, must be taken into account (Vanegas et al., 1996).
Different stakeholders may have different priorities even when striving toward the same goal (Huovila et al., 1998). To take an oversimplified example one could imagine that life cycle costs, indoor conditions, and comfort would be the main objectives for the owner in and environmentally friendly building project. At the same time, environmental burdens during the operation phase, adaptability, and service life may be the main concerns if we regard the nature as a customer whereas safety, land use questions, and accessibility are placed high in the agenda of the society. What is important for all these customers is value over time. The investor may emphasize in maximizing profit instead of minimizing cost, which can be different things.
Method and Tool for Requirements Management
VTT Building Technology has developed a method and a tool, EcoProP, to set and manage performance requirements in a building construction project. It is based on an extensive building property classification, VTT ProPTM. In addition to building performance properties, it also contains environmental and cost properties and requirements for the realization process. EcoProP provides a path for the realization of a thorough performance-based project definition. The performance-based requirements give designers/engineers a possibility to fully exploit their knowledge accomplishing creative and flexible solutions. When requirements are performance based the variety of procurement methods is larger. The contractors can improve design and also benefit from this (Lahdenperä, 1998). EcoProP has been implemented in different building projects consisting of nurseries, office buildings and housing. The experiences so far have been promising.
Exhibit 1. Approach for Environmental Management in Construction
Exhibit 2. Environmental and Sustainability Issues in Construction
That approach and tool can be used for all kinds of buildings. Its first applications have been nursery schools, offices, and houses. It can be used for setting objectives of various natures. It is, however, developed and currently implemented in eco-ef-ficient building projects with the emphasis on management of desired indoor conditions, service life, and adaptability together with controlled environmental burdens during the operation of the building in addition to the traditional project boundaries with cost and time.
Exhibit 3. Different Stakeholders and their Priorities
The end-result of an EcoProP-based requirements setting is a project brief. Selected requirements are gathered to a single, color-coded Excel sheet. Color codes give a quick view of the requirements level of the project. This sheet can be saved to a separate file that can be distributed via e-mail or published in the project Web site. Furthermore, selected requirements can be copied to Word automatically to offer a possibility to edit requirements in a text file. This Word file acts as a “project memory” when in the later phases of the project requirements are changed. A profile of the selected requirements can be created after the user has set targets for the project. The profile shows the average requirement level of each property. The profile contains also a reference line. Company or organization can set a reference level to validate requirements of a single project.
State Real Property Agency (SRPA) has recently added procedures to the quality system to enhance the eco-efficiency of their building construction projects. The first step was to add “green forms” between the other descriptions of work to be done in a particular phase of the project. After the managers of SRPA that people have adapted to use these green forms, color was changed to similar with the rest of the forms. To also have requirements concerning eco-efficiency had become part of normal process. However, the feeling among the project managers was that they needed better tool to tackle to whole requirements setting procedure. Browsing through lists of papers was too time-consuming and unproductive. EcoProP was tested in a project where the project manager had already created a brief focusing mainly on the qualitative requirements of various properties like adaptability and energy consumption of the building. The intention was to transfer these requirements to EcoProP to test the tool. However, it became obvious that it is more beneficial to follow the path provided by EcoProP and also to add requirements that were not in the original brief. The general feeling amongst the participants was that EcoProP makes the user to think more precisely. Also, the previous abstract and unclear requirements got a more exact definition. The requirements were set in a session where the project manager, the building services specialist, the architect, the environmental expert of SRPA, and two experts from VTT Building Technology were present.
Exhibit 4. Results of Requirements Setting Session
Exhibit 5. Environmental Indicators
Other test cases included nurseries developed by the Construction Management Division of the City of Helsinki (HKR). HKR provides building construction services to various departments of the City. HKR manages the building project acquiring designers, engineers, and builders. HKR creates the brief from the original project definition. The method to set requirements differed from the SRPA case. Since HKR has large a building stock to maintain they have a lot of information on actual energy consumption, maintenance costs, etc. They exploited this knowledge to set requirements that necessitate improvement to eco-efficiency of the building. For instance, energy consumption should be 20% less than in the existing buildings.
Cole (1998) sees that greater communication and interaction between members of the design team and various sectors of building industry are generated when environmental assessment methods are used. This communication encourages dialogue and teamwork to realize more environmentally friendly built environment. Even if EcoProP is not an assessment method, the same benefits are realized. Based on the piloting experiences, EcoProP has proven to increase discussion, commitment, and teamwork. The original needs of the stakeholders get documented and the target-iteration processes can exploit performance requirements to avoid cutting essential, often eco-efficient requirements.
EcoProP can be used in team sessions or a single user can apply it for setting requirements. EcoProP in a team session improves the quality of the selected targets and goals of the project since participants challenge each other's ideas and selections. Also, the commitment of the project team members increases. Some improvements are needed for the tool to make it an essential part of the project definition of the piloting companies.
In many cases, the objectives and consequences are complicated to measure, or their outcome can be estimated too late in the process to affect in the decision-making process. One way of progressing is to introduce indicators that can predict the behavior later in the life cycle. Different kinds of indicators can be applied instead of precise values—even some solutions can be judged and compared as indicators.
Our future plans include development and implementation of environmental indicators. These measures are to indicate future environmental consequences that can be verified afterward. The building-level indicators will be extended to meet the city or community level indicators that are used (e.g., for indicating social sustainability). The challenge is to find correlation with the environmental quality of the facility and its value to different customers.
Exhibit 6. Performance and Different Economies
Discussion
The arguments to set and means to meet environmental objectives may be different in different societies, economies, and environments. The direction can already be addressed if we want to improve the quality of life by improving the quality of our built environment. The environmental economy can be included amongst other actors, like the monetary economy. The performance of the building can be described and verified. Methods and tools are available to support this approach and there's more to come. What is still lacking can be developed. All actors are invited!
