SPECIALIZED ENERGY CONSULTANTS FOR ARCHITECTURAL HERITAGE

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1 SPECIALIZED ENERGY CONSULTANTS FOR ARCHITECTURAL HERITAGE Authors: M. de Bouw (1,2), S. Dubois (1), S. Herinckx (1), Y. Vanhellemont (1) (1) Belgian Building Research Institute (BBRI), Dpt. Sustainable Development and Renovation, Lab of Renovation, Av. P. Holoffe 21, B-1342 Limelette, Belgium (2) University of Antwerp, Dpt. of Design Sciences, Master of Monument and Landscape Conservation, Mutsaardstraat 33, B-2000 Antwerp, Belgium ABSTRACT Making heritage buildings energy efficient is very little established in Belgium. Several reasons can explain this as, for example, the fact these buildings are exempt from the Belgian Energy Performance of Buildings Directive, the fact that the application of energy-saving measures is often difficult to reconcile with the heritage values of the building, etc. Nevertheless, the energetic optimization of heritage buildings, combined with renewable energy, offers many opportunities (reduction of greenhouse gas emissions of this substantial collection of buildings, making use and occupation of the buildings more attractive by reducing bills and improving comfort, etc.). But achieving this without harming the heritage values and minimizing/eliminating all risks for the building itself, implies a well thought-out approach. These concerns are at the basis of the current seven-year project, which aims to concretize the measure "Specialized energy consultants for architectural heritage", that was incorporated in the new Climate Plan of the Flemish Government. The training project is targeted at (experienced) restoration architects, aiming to scale up their skills with regard to energy efficiency for heritage buildings in particular. The proposed paper wants to show exactly how this specialized training will be elaborated and how it will be implemented in Flanders. To do so, the paper will present the conception of the project as well as the five major steps of its execution: 1. The organization of an accessible energy support service focused on restoration architects, 2. The development and implementation of a specialized energy consultant training course for restoration architects, 3. The development of an accreditation system or procedure, based on the above mentioned training course, 4. The setup of a monitoring campaign on several cases of the restoration architects, who attended the elaborated training course, in order to monitor the results and impact of the retrofitting in real circumstances, 5. The implementation of a feasibility study regarding the embedding of the abovementioned training course in the existing Belgian educations for restoration architects (universities, specialized trainings, university colleges, ). Key words: building heritage, energy efficiency, heat air and moisture, architectural value, heritage value, holistic approach 1

2 1 INTRODUCTION Today, the impact of human activities on the environment is well-established. It caused a deep questioning of industrial traditions and citizen behavior. The construction sector is slowly mutating into a more green, social, creative and innovative industry and the governments tend to encourage this transformation process. Buildings are still responsible for about 40% of the total final energy requirements in Europe, more than the transportation sector [1], [2]. As a direct consequence, the legal framework for the construction industry is evolving very quickly. At the European level, the Energy Performance of Buildings Directive (EPBD) has established a large set of measures to cope with the Union s 2020 main objective to reduce greenhouse gases by 20% compared to 1990 levels [3]. The nearly zero-energy buildings principle is included within EPBD requirements and states that by 31 December 2018, all new building owned by public authorities must have a very high energy efficiency [4]. The same goal applies for every new building after 31 December In Belgium, the three Regions (Flanders, Wallonia and Brussels) are responsible for the local transposition of the EPBD. It includes measures for construction, re-construction and retrofitting activities. In 2011, the Flemish government determined standards for energy performance of new buildings, which are limits imposed to the primary energy consumption (or E-levels). The Energy Renovation Program (ERP) by 2020 was also implemented for existing buildings [5]. Until now, however, there has been large exceptions to these regulations when dealing with architectural heritage. Yet, in the timeframe, this sector could save some 8,5 million tons of CO 2 equivalent [6] if the involved actors (restoration architects, owners, contractors, etc.) spend more attention to the energy performance of the protected architectural heritage. However, the ability to carry out energy saving measures in such buildings, without affecting the heritage values or causing collateral damage, is an important factor related to the operating costs as well as the comfort of these buildings. Indirectly, this could also result in a better preservation of the heritage, because occupied buildings are generally much better preserved than the non-occupied ones. The current project aims to capitalize on the potentials of energetic improvement to create a permanent structure where specialized energy consultants are trained for the architectural heritage sector. It will allow the owners/users of a heritage building to call upon such specialized professionals who should be able to formulate an evaluation of its energy (d)e(f)ficiency, but also to propose realistic and feasible measures to optimize this energetic characteristics in line with the building s heritage values. 2 PROJECT DESCRIPTION 2.1 Position in the Regional action plan The third Flemish Climate Policy Plan (FCPP) covers the period It consists of an action framework that can be divided into two closely bound sections. The first part is the Flemish Mitigation Plan (FMP), the purpose of which is to reduce the emissions of greenhouse gas emissions in Flanders. The second one is the Flemish Adaptation Plan (FAP), which aims to characterize the vulnerability of that Belgian Region regarding climate change as well as to offer ways of improving its ability to face it [7]. The measure of the FMP [6], which concerns energy consultants, was at the root of the project presented here. In the FMP framework, the energy consultants are supported by the public aid that is made available to various sector federations and non-commercial organizations to sensitize, inform and guide their target audiences (construction professionals, families, small and medium enterprises) in the field of energy savings and renewable energy. 2

3 In October 2010, the Flemish administration chose to implement a new subsidy framework oriented towards a better streamlining of projects, a longer term funding and a better interaction between individual energy consultants. In addition, the measure stipulates that the Flemish Climate Fund associated to the FCPP supports the improvement of energy guidance in various sectors, which includes energy consultants specialized in architectural heritage. Concerning this last point, the FCPP mentions the following actions: organization of an energy desk for heritage buildings, elaboration of a training and certification procedure, and monitoring of the results. 2.2 Target audience and driving committee In a first step, this project will focus on restoration architects as a priority. They will have to combine the knowledge in the field of heritage values with experience in the area of reducing the energy requirements. Through this small group (± 50 restoration architects in Flanders), other actors such as the owners and/or contractors will be reached eventually. The steering committee of the project is composed by representatives of the various stakeholders in this project. That is the target audience, the Flemish educational institutions related to building restoration, and administrations related to environmental and energy management. The involvement of educational actors is essential in order to efficiently implement the training procedure once this is elaborated. 2.3 Holistic approach for the energy optimization of heritage building A building can be divided into three physical domains, viz. the heat, air and moisture fields, and three geometrical regions, viz. the building envelope, the interior air region and the exterior air region [8], [9]. Existing constructions exhibit whether or not healthy a complex interaction between these domains that results in a locally-specific equilibrium. Interventions that aim to increase energy efficiency could seriously distort this balance if they are not executed in a thoughtful way. In heritage buildings the arising consequences can have an important impact on preserving the architectural values. A holistic approach is thus essential in energy optimization of buildings with high historical significance and a compromise must always be carried on between energy optimization and conservation of heritage values. Figure 1: The building geometrical (left) and physical (right) domains In the Belgian regional transpositions of the European EPBD, the improvement of energy efficiency is typically considered through the E-level defined as: E = 100 E cons /E ref 3

4 Where E cons is the primary energy consumed by the building and E ref is the reference value for a representative consumption, both on an annual basis. In the holistic approach with considerations of heritage value, only aiming to reach a predefined E-level is not a pertinent method. Instead, the accumulation of interventions on several fronts is preferred, aiming to achieve the greatest possible improvement in terms of energetic performance, within the limits set by the necessary preservation of heritage values. Each intervention is considered with respect to its potential impact on the equilibrium mentioned above and is complemented with specific adjustments where necessary. Globally, individual energy interventions can be related to various elements of the building: insulation, radiation, thermal inertia, ventilation, glazing, shading and HVAC systems. In the proposed project, the energy issue will addressed on several action fronts. First with the more classical approach in energy optimization which is to minimize the direct energy losses. This can be achieved by various means such as improving the airtightness, applying additional thermal insulation, replacing the existing glazing, etc. In addition, indirect savings can be obtained through modifications of the comfort conditions in the building. The major goal of this second action pole is the reduction of energy need for cooling or heating. Examples of such interventions are the dampening of indoor humidity fluctuations or the application of heat reflective coating which are expected to modify the operational temperature of the rooms. A third way of improving the energy efficiency is to look for energy production systems that induce less CO 2 emissions. Finally, the modification of the occupants behavior is essential: rationalizing the use of lighting, heating and any other energy-consuming installation and optimizing the use of natural resources (e.g. sun). It seems clear that the set of energy-related interventions cannot be separated from the classic restoration interventions, in order to meet the principle of the holistic approach. A good restoration of the building, with suitable materials and technologies, is a necessary condition for achieving a comfortable and energetically-performant building. As stated above, energetic interventions have an impact on the existing balance in the building, and they can cause side effects that affect their conservation. They can strengthen existing pathologies or sometimes eliminate them. For example, increased heating and ventilation in a basement can lead to increased damage to masonry or finishes by salt crystallization. The installation of insulating glazing can lead to an increased risk of condensation on walls, with mold growth and deterioration of materials as a result. The energy optimization process should therefore include the typical investigations which always precede a restoration procedure as well as the restoration interventions. The (iterative) process is conducted as follow: 4 a) Determination of the patrimonial value of the building: establishing the reasons that explain its protection status, and as a consequence, the extent to which interventions are possible. This analysis is performed for each room or element, in order to determine which intervention can be applied in which location. b) Diagnostic of the current state of the building: picture the envelope and the mechanical systems as well as the structural and energetic conditions. Every change that is planned regarding the function of a room should be studied during this step. c) Elaboration of an intervention plan: analysis of the current state of the building and elaboration of an interventions list, both on restoration and energetic points of view. Again, it should be reminded that restoration and energetic interventions may interact with each other (and an iterative approach is necessary).

5 d) Restoration interventions: suppression of all damage causes where possible. e) Energetic interventions: in parallel with previous step. The energetic interventions can provide a way to solve, reduce or at least make manageable some of the pathologies of the building, and strongly improve the usability (e.g. costs, comfort, ) of the building. f) Monitoring of the building state and behavior after the restoration: determining if the building is behaving completely the way it was foreseen, and keep an eye on the evolution of the building s state in order to predict and adapt correctly maintenance activities. 3 PROJECT EXECUTION In order to meet the objectives of the project, the following five-stage plan for the period was developed: 1. First, an Energy Desk will be organized. This interactive guidance platform in the form of a website should provide assistance to the restoration architects of the target group who are facing the need to improve the energy efficiency of heritage buildings. Each guidance or advice emanating from the energy desk should be coupled to a concrete project (the focus will be put on inhabited or permanently used listed buildings). The systematic tracking of the provided advices will result in a database comprising the topics of the requests, the administrative data concerning the questioner and the building, the particular problems and the (innovative) solutions that were proposed. This database will enrich the knowledge concerning the technical solutions that can be applied in energy optimization of heritage buildings, or the combination of solutions that proved to be efficient. In order to complete this database, also data and case studies from the literature and from abroad will be screened. 2. Parallel to the development of the above-mentioned Energy Desk, a training program towards specialized energy consultants (viz. restoration architects) for heritage buildings will be created. In a first step, the necessary documentation and practical knowledge will be gathered in order to elaborate a comprehensive lessons package. This first step is closely related to the experience gained from the Energy Desk. Then, a concrete training will be offered to the target group of architects on the basis of this package. 3. In the third phase, an implementation of an accreditation system will be investigated. The feasibility and entire methodology for such an accreditation system has to be examined, with all the associated criteria. By offering a clear recognition system, the governmental organization responsible for the preservation of Architectural Heritage will eventually possess if desired a way to monitor the quality of the interventions on heritage buildings carried out by the specialized consultants Once the target group has successfully complemented the training program of Phase 2 (and following positive evaluation the accreditation procedure of Phase 3), a long-term monitoring phase will take place in the period This monitoring campaign will generate precious information on the effects of this training campaign and the solutions within the database, which in its turn will be used to optimise the training and database.

6 5. Parallel to the above-mentioned phases, a feasibility study will be carried out which will check whether and how the elaborated lesson packages can be embedded into the regular course programs of the Flemish restoration educations. This phase will result in a key note that summarizes the problems and proposed solutions for embedding the lessons package. In additions, there will also be reports of all the consultations with the decision makers involved in formation and education. A general diagram illustrating the stages of the project is given in figure 2. Once the project reaches its end, some possible after-project steps have to be considered. First, there is the elaboration of a permanent Energy Desk, i.e. the structuralization of the solicitationportal (Phase 1 above), where recognized restoration architects can address their questions concerning energetic aspects of heritage. In addition, those architects who have followed the formation process could be monitored concerning the quality of their intervention as the new decree of the Flemish Region concerning protected buildings will open the possibility to develop a quality label system for building heritage entrepreneurs. Figure 2: Project stages 4 CONCLUSIONS This paper describes a project taking place in the period that is intended to answer the need for energy consultants specialized in architectural heritage. Beside clear benefits in terms of greenhouse gases emissions, the objective is to provide practical answers for restorations architects to the solicitations of owners/users who show the will to improve the energy efficiency of their heritage buildings. The solutions are not straightforward as the risk to affect the underlying architectural or cultural values is real. In order to reach this goal, the creation of a specific training process for restoration architects is central within the presented project. 6

7 First the normative context of the project was presented. Indeed, the latter answers a specific measure included in the Flemish Climate Plan related to the formation of specialized energy consultants. Then, some principles for the energetic renovation of heritage buildings were proposed and described. These form a holistic approach to energy efficiency optimization where the balance between heat, air and moisture transfers are carefully taken into account. Finally, the detailed overview of the project execution was depicted. The five main stages were explained along with the relationships that exist between them. The key measure is the elaboration of a training program in order to train specialized energy consultant for architectural heritage. This teaching material is going to be constructed on the basis of proper experience of the experts involved in and around the project, the experience acquired through the implementation of an Energy Desk, and improved later with a monitoring program carried out on protected buildings which were energetically improved. The development of an accreditation system will also be evaluated. At last, the integration of the lessons package in the regular course programs of the Flemish educational institutions for restoration architects will also be studied. 5 REFERENCES [1] Buildings Performance Institute Europe. (2011). Europe's Buildings under the microscope. BPIE. Retrieved from [2] Pérez-Lombard, L., Ortiz, J. & Pout, C. (2008). A review on buildings energy consumption information. Energy Build, 40(3), [3] European Union. (2010). Directive 2010/31/EU of the European parliament and the council of 19 may 2010 on energy performance of buildings. EU. Retrieved from [4] Hermelink, A. et al. (2013). Towards nearly zero-energy buildings: Definition of common principles under the EPBD. Ecofys by order of the European Commission. Retrieved from [5] Flemish Government. (2012). Flemish reform programme: Europe Retrieved from [6] Departement Leefmilieu, Natuur en Energie. (2013). Vlaams mitigatieplan Retrieved from [7] Flemish Government. (2013). The Flemish Climate Policy Plan: , a summary. Retrieved from [8] Costola, D. (2011). External coupling of building energy simulation and building element heat, air and moisture simulation. PhD Thesis, Technische Universiteit Eindhoven, Eindhoven, the Netherlands. [9] Janssens, A. et al. (2008). From EMPD to CFD overview of different approaches for Heat Air and Moisture modeling in IEA Annex 41. Proceedings of the IEA ECBCS Annex 41 Closing Seminar, Copenhagen, Denmark. 7