Open House meets in Brussels

On Thursday, 25 July, we attended the Brussels Launch Event for the Open House (OH) project.

As stated by the OH steering group… the OPEN HOUSE project aims to merge existing methodologies for sustainability assessment of buildings towards a common view. With the aim of being widely adopted in Europe, the OPEN HOUSE methodology is developed in a fully transparent, collective and open process, with extensive communication and interaction between all stakeholders.

The small Brussels workshop event marked the successful completion of this project, which is of considerable interest from technical, process and market viewpoints. The many actors in this field range from essentially commercial systems such as BREEAM, DGNB, HQE and LEED; to NGOs with a permanent interest in the area but no specific system; and finally to government-funded research groups set up to encourage the development of a common model of building performance assessment within a defined time frame.

Open House is one of most significant of these consensus-oriented R&D initiatives. You may not have heard of it, but the project had a 3 ½ year duration involved 20 partners from 11 European countries, and received 4.9 million Euro from the EU. Another project of a similar nature is the SuperBuildings project (completed in 2012). CESBA, the Common European Sustainable Building Assessment project, has similar goals but is not financed by the EU.

One of the driving forces behind the formation of the OH project is the frustration of the research community with the lack of commonality in the methods used by the major commercial systems, which limits the European industry’s understanding of sustainability and impedes the development of relevant common standards. Any move towards commonality by promoters of commercial systems tends to focus on market domination, e.g. we will have more commonality and less confusion when everybody is using my system… A partial step to commonality amongst commercial systems was the establishment of Sustainable Building Alliance, but this effort has limited participation beyond the main actors, BREEAM and HQE.

The OH response to this situation was to design a process that would aim to review the structure and indicators used by major existing systems, to develop proposals for a common approach in the form of an on-line assessment system, and to test the selected approach in case studies. The system has been tested on 65 case studies in 35 European countries, and analysis of the results has fed back into modifications of the methodology. It should be noted that all except three projects are office buildings, and only 15% are refurbishment projects.

A strong emphasis in the project has been on transparency of the process and all project results are to be freely available, except for project information held back by their owners.

One of the main issues in the project was to review the performance indicators used by various systems. As previously noted, the OH researchers found little consistency between the indicators used by the existing major systems. They produced a first set of 56 project indicators, and after reviewing the case study results a final set of 46 indicators was produced.

The OH assessment framework is composed of 6 issue categories:

- Environmental Quality
- Social/Functional Quality
- Economic Quality
- Technical Characteristics
- Process Quality
- The Location





The three central issues of Environmental, Social/Functional and Economic Quality reflect, more or less, the three main elements of sustainability. The addition of Technical Characteristics and Process Quality makes the overall structure identical to the DGNB system, partly explicable by the fact that Fraunhofer is coordinating the technical aspects of the project. The Technical Characteristics issue has its equivalent in many other systems (e.g. the Service Quality issue in SBTool), but most of the OH Process Quality indicators are not found in other systems except for DGNB.
The question of how relevant process indicators are deserves a separate analysis, but our view is that some process issues are irrelevant with respect to the question of how the building is actually performing (e.g. the Integrated Design Process is very likely to support high performance and should be emphasized as a guideline, but there is ne definite causal relationship). However, many workers in the field would disagree with this view.

One of the most controversial issues in the development of performance assessment systems is the question of weighting. Most researchers and users agree on the need for some way to identify variations in importance of specific indicators. In other words, how important is indoor air quality v. acoustic performance? A weighting system is especially important where overall point scores are the intended outputs of the system. OH provides a weighting system for criteria (see deliverable D1.5) at three levels: sub-indicators on a 0 to 4 integer scale, indicators also with a 0 to 4 scale and finally the three main issue areas Environmental, Social and Economic, at 33% each.

OH has carried out panel and on-line surveys to obtain a broad response on appropriate indicator weights, although it can be argued that, for example, a vote resulting in a higher weight for indoor air quality than for primary energy consumption, would be meaningless if not based on a truly objective weighting scale. And the 33-33-33 weighting for Environmental, Social and Economic issue areas is hard to defend on any logical basis. It should also be added that this even-handed approach also results in Economic criteria having a much greater effective weight than Environmental or Social criteria, since there are relatively few Economic criteria in the system.

The OH technical team is currently working on an algorithm for establishing indicator weights in a more objective way. The concept and weighting tool will probably include the intensity, extent and duration factors used by SBTool, and will be available by the end of August.

Where does the project go from here?

The EU funding, which was generous, is now over but the main actors involved will probably use their day jobs to promote the ideas developed within the project. This may extend to influencing the evolution of existing assessment systems and to participating in the iiSBE SB Challenge process for SB14. But it will definitely not extend to Open House developing a commercial system of their own.