Sustainable Assessment of Rehabilitation Works of Residential Buildings, in France

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1 Sustainable Assessment of Rehabilitation Works of Residential Buildings, in France Ana Miguel CUNHA; Xavier DANIEL Group QUALITEL ; 1 INTRODUCTION TO THE RESIDENTIAL REHABILITATION SECTOR Sustainable new and existing construction became one of the main priorities of French government policies. Nevertheless, the ageing residential building stock and its need of renovation are themes that haven t yet received enough attention by building owners. Even after its definition, Rehabilitation works currently suffer of a lack of coherence due to the inexistence of global diagnosis of the asset and a comprehensive perspective of the project. The particularities of the Residential Sector context led QUALITEL to develop a multicriterion certification method (expressing a technical and environmental profile) that encourages construction players improving existing dwellings to go beyond regulatory requirements through the certification of their rehabilitation projects. 2 THE ASSOCIATION QUALITEL AND ITS BUILDING CERTIFICATION SCHEMES Created in 1974 at the initiative of the French Ministry of Housing, the Association QUALITEL is an independent and non profit body, specialized in the environmental and technical certification of domestic buildings. The Association QUALITEL, namely its board of Directors, is composed of representative members of all the construction sector, grouping professional organizations of the residential, financing and construction sector, associations of consumers, public authorities and technical expertise bodies, all for the concretion of a common goal: the promotion of housing quality, through building certification and users information and through the development of documents, supports and frameworks allowing to achieve this goal. The technical reference frameworks, used for every QUALITEL s certification scheme are always approved by consensus, by all the members. This allows the development and approval of documents and procedures that are sufficiently ambitious to considerer the users and government s expectations, but that are realistic and adapted to the efforts that the industry and construction players are able to do, at the present and in the next years. Since the beginning of its activity, QUALITEL and its subsidiaries have carried out the assessment of more than homes in France. Confirming the QUALITEL s credibility, transparency and experience, more than dwellings have registered for certification in 2008 next to the Group QUALITEL. In addition, QUALITEL is a founding member of the international network Sustainable Building Alliance (SBA). 2.1 A Building Certification offer for all the Residential sector: The Residential Sector is nevertheless more complex and linked to national regulations and specificities than the tertiary Buildings (offices, commerce, etc). This awareness led QUALITEL to develop a specific residential certification offer, based on a multicriterion approach, so that all the dimensions of 1

2 sustainability (economical, environmental and social ones) can be integrated and assessed with an adapted certification scheme, showing an environmental profile. This approach stirs up the construction players to go beyond the prescribed requirements and regulations. The Association QUALITEL devotes itself to the approval of the certification reference systems, to the information of the General Public, and to the development and diffusion of good practices observatories. The actual certification activity is carried out by its three subsidiary companies: CERQUAL, CERQUAL PATRIMOINE and CEQUAMI: CERQUAL subsidiary for the certification of the NEW residential buildings. CERQUAL PATRIMOINE subsidiary for the certification of residential EXISTING buildings and rehabilitation works. CEQUAMI subsidiary for the certification of detached houses. Actually, if the certification activity of QUALITEL started assessing the technical, economic and comfort quality of residential buildings, its assessment schemes soon developed an environmental version to integrate environmental criteria able to promote sustainable housing that would contribute for increasing environmental building performance but without forgetting essential comfort and technical basic requirements. That is why the current QUALITEL certifications have always a more technical quality and comfort oriented version, as well as another version including in addition environmental criteria and management requirements for the project (which are identified with the termination name HQE or H&E). This allows the different players of the Building Sector to integrate increasing levels of technical quality, allowing all of them to gradually evolve to the generalisation of environmental practices. 2.1 A specific multicriterion approach for Existing Residential Buildings: In order to improve the quality of existing dwellings, and the integration of global performance oriented strategies in the existing domestic stock, QUALITEL launched the Certification Patrimoine Habitat (manly technical and comfort oriented) and its environmental certification version Patrimoine Habitat & Environnement. For both cases, the certification is always preceded of a building diagnosis (BPH Bilan Patrimoine Habitat) for the analysis of the actual state of the building. This certification reference framework requires that a competent specialist verifies the whole set of estimated works. In this paper only the certification Patrimoine Habitat & Environnement will be described. The certification Patrimoine Habitat & Environnement (PH&E) was launched in 2006, for the environmental assessment of existing Residential Buildings. It is consistent with the HQE French approach in terms criteria. This certification is an independent mean for owners (or co owners) to obtain an evidence of the improvements achieved with building rehabilitation, through the communication of a profile characterizing the performance attained in a certain number of patrimonial, environmental, technical, and comfort issues. In this context, the certification of existing buildings easily justifies its utility. Wanting to apply new construction standards to rehabilitation projects, generally leads to costs that are disproportional to the performance improvements achieved. Therefore, a performance optimization effort must be carried out for each rehabilitation project, this role belonging undoubtly to design teams and developers. There aren t rigid rules for rehabilitation: each project must be studied case by case. In such a little regulated field (like the rehabilitation of existing buildings), the certification of this type of buildings and works, appears as a provider of transparent orientation and guidance for the project development, but 2

3 also as a provider of an independent and objective assessment of results, including the level of progress in terms of energy savings. QUALITEL s French certification responds to global sustainability concerns and conciliates priorities of progress and respect of actual and future ecological balances, users health and comfort requirements, as well as inhabitants increasing environmental awareness. The requirements of this Certification are grouped in four main themes, composed of a total of 11 subjects that cover the main technical and environmental particularities of Buildings. 3 AN ENVIRONMENTAL ASSESSMENT APPROACH ORGANIZED IN TWO STAGES 3.1 The Building Technical Diagnosis: Bilan Patrimoine Habitat [BPH] The Bilan Patrimone Habitat became the French reference tool for the technical assessement of the quality of the Habitat. It makes it possible to identify the strengths and weakness of an existing residential building and examines aspects linked to occupation comfort. Conceived with the participation of building owners, professionals and users, the BPH provides an overall assessment and a synthesis of the residential built inheritance through simultaneously a technical and a documentary examination, integrating exploitation and maintenance considerations of the project. Being a precondition step of the certification, it can also be used as a multicriterion decision making tool for any patrimonial rehabilitation or maintenance action, such as a Strategic Patrimonial Plan, for instance. The Bilan Patrimone Habitat is a building technical diagnosis/assessment carried out by an experienced professional. Quite often, the building owner hesitates about the interest of carrying out deep rehabilitation works. It is therefore necessary to provide him with a clear and synthetic document, reporting and describing the existing anomalies. A strategic conclusion provided by the assessment body, and organized in a synthetic table, allows the owner/developer to consider interventions/works in function of its degree of urgency, giving the owner an indication of the time that he approximately has to carry out the different works of rehabilitation or renovation. This can help him to set strategic priority actions and works. So, the Bilan Patrimoine Habitat (BPH) is a diagnosis composed of a documentary analysis and of a technical analysis, allowing the understanding of the general conservation state of the Building, and the identification of the existing fields of progress. For its assessment, the Bilan bases itself on factual elements, and do not provide any architectural and aesthetic judgment. The BPH is delivered by CERQUAL PATRIMOINE (subsidiary of QUALITEL) and can be applied to multifamily residential buildings or to a whole group of houses, of more than 10 years old, in single or joint ownership (a specific version is available for multiownership buildings). The BPH was developed in order to allow the achievement of the following goals: To work on the basis of validated principles and use a consensual assessment tool (a first stage of diagnosis assessment which necessarily precedes certification), promoting agreement on the reference frameworks adopted by the professionals, owners, investors and occupiers (who jointly developed the method, in a consensus basis). 3

4 To identify, with independent evaluators, and through a technical examination, the state of conservation of the building, its qualities of comfort and use and its performances in different fields. o Within the realization of the Bilan Patrimoine Habitat, a Technical Report is elaborated, containing an analysis and inventory of the building state. Additionally, a Documentary Analysis is done in order to compile information on the standards and regulations the existing building must comply with, comprising exploitation and operation data, as well as information on the diagnosis and maintenance practices (Figure 1). Figure 1 Composition of a Bilan Patrimoine Habitat: a Technical Report and a Documentary Analysis To evidence the strong and weak characteristics of the residential building, on the basis of clearly identified checkpoints, known beforehand by all the players, promoting the transparency of the whole process and clearness of the appreciation method. o o The Building elements and systems that are controlled during the BPH diagnosis, refer to varied parts of the built construction, such as the exterior spaces, façades and roof, interior common areas (halls, stairs and lifts), technical equipments and systems, 5% to 10% of the dwellings interiors, acoustics, thermal comfort and energy performance, parking accesses, fire security, domestic waste disposal, users information, body protections (railings, ), etc. Therefore, the assessment is based on the control of predetermined parts of the building, where more than 500 elements (checkpoints) are analysed, giving origin to a synthesis sheet where all these elements are rated from A (new or almost new condition) to D (obsolescence, function not filled). This BPH rating system (A, B, C or D which depends on the conservation state of the building parts and their respective functionalities) becomes an important and complementary element for the work of the architect and design teams, because it is consequently a technical photograph constituting a starting point for the rehabilitation and helping to determine the aspects that shall suffer corrective measures (namely those systems/elements that achieve the level C or D of the BPH diagnosis). 4

5 To provide the owner with decision making elements for the rehabilitation, and to initiate him in a preliminary action for building certification. o o Being a simplified instrument that allows the appreciation of the qualities of a building, in a transparent and economically feasible way, the BPH provides a preliminary technical building profile. As a preliminary diagnosis of the state of the art, the Bilan Patrimoine Habitat becomes thus a strategic tool for the definition of the rehabilitation priorities, and it is a precondition and mandatory step before the certification can be requested for an existing building. The clarity of the appreciation and rating system makes it clear for the certification customers to understand the modalities and principles of intervention. This technical, environmental, comfort and operational appreciation of the building can be extremely helpful for strategic decisions and for the definition of priority works of rehabilitation, as well of the performance levels for certification. Figure 2 Bilan Patrimoine Habitat Rating system and its synthesis Sheet Complementarily, the whole set of diagnosis and carried out by QUALITEL Group (namely by the subsidiary CERQUAL PATRIMOINE), are collected and analyzed in the Existing Building certification Monitoring & Observatory, which allows the publication of up to date considerations about the current state of the French residential stock of buildings. 5

6 3.2 The Second Stage: The certification of rehabilitation works of Existing Homes: Patrimoine Habitat & Environnement [PH&E] The Bilan Patrimoine Habitat is then a Diagnosis that precedes the certification request. Nevertheless it can be done without obligation of ulterior certification request. QUALITEL (with the subsidiary CERQUAL PATRIMOINE) has developed two certification offers for existing homes: One being oriented for the assessment of the technical and comfort issues, and another one covering all those issues but integrating environmental criteria Patrimoine Habitat & Environnement: A certification that allows dwellings owners to give evidence to the improvements made in the building, through a specific certification profile that characterizes the building performance. An independent third party evidences the response given to a certain number of patrimonial, technical, environmental, economic and comfort requirements. This certification appears in a context of increasing environmental concern and awareness, and conciliates imperative needs of progress and respect of the actual and future ecological balances, as well as of occupants health protection and indoor quality. This certification is applied to rehabilitation projects of residential buildings or groups of houses, all aged of more than 10 years old. It establishes minimum performance levels to be reached for different technical, comfort and environmental themes. The Certification Patrimoine Habitat & Environnement takes into accounts 4 families of criteria: the technical and environmental organization and information about the Project, the quality of the shell (façades, roof, ) and the common areas, the fire protection and the health conditions for the occupants, and finally the comfort and performance of the homes. The technical reference framework is composed of 11 themes (Figure 3) declined in 21 subjects. Figure 3 The 11 Technical and Environmental Themes of Patrimoine Habitat & Environnement The 11 main certification themes cover different criteria, namely: 1) Organization and Project Management: integration of environmental management principles, definition of a technical and environmental building profile accordingly to the site specificities and to the stakeholders/occupants expectations; processes control during Design stage; organisation of the Project Stages in order to achieve the defined performances, consideration of the results given by the Bilan Patrimoine Habitat regarding the Building real improvement potential. 6

7 2) Green Worksite: worksite organisation, construction waste management, control of the construction building site impacts, reduction of the harmful effects 3) Green Attitudes & Actions: Information of the inhabitants regarding the works to be done, good environmental and health practices in terms of dwellings occupation by the users, rules of use, knowledge/awareness about the home s equipments, etc. 4) Fire Security: in order to improve the security against fire in existing residential buildings. 5) Sanitary Quality of the Homes: to take into account criteria allowing the improvement the indoor air quality and water, through a better knowledge, understanding and control of the possible pollutants and their sources. 6) Accessibility and Quality of Use: consideration of the ageing evolution of the occupants, and improvement of the adaptation features to the different human handicaps 7) Shell & Roof Quality: analysis of the state and quality of certain components of the shell (façade, roof, openings and frames); consideration of the geometry of the railings and their security. 8) Equipments and Comfort of Common Areas: State and quality of certain components of the halls, circulations and common areas, as well as of collective technical equipments and lifts; consideration of the production and recycling of domestic waste, of the geometry of the railings, of the safety of the building, etc. 9) Dwellings Technical Equipments: to take into account the features of the domestic technical equipments of the homes, such as electrical, plumbing and sanitary installations and ventilation/air handling systems. 10) Energy Performance: Improvement of the energy performances of the building on the basis of a target set in comparison to a conventional primary energy consumption 11) Acoustic comfort: Improvement if the acoustic comfort of the dwellings, regarding the interior and exterior noise, for impact and airborne noise. In order to obtain the certification Patrimoine Habitat & Environnement, the owner/client must define the technical and environmental profile to be achieved. He must however comply with at least 6 of themes, where 4 of them are always mandatory. The 4 mandatory themes are the following: o Organization & Project Management (1) o Green Worksite (2) o Green Attitudes & Actions (3) and o Energy Performance (10) The 2 optional themes the building must comply with are any other those referred in the Figure 3 above. Nevertheless, the topics that aren t selected must systematically comply with the technical minima exposed in the reference framework of the certification Patrimoine Habitat & Environnement. Actually, a Rehabilitation or Renovation Project doesn t necessarily regard all the building technical specialties and characteristics. Without being less complex than a New Building Project, the Design and Execution of rehabilitation works won t always act over all the elements and systems of a Building. That is why the Certification Patrimoine Habitat & Environnement demands the compliance with at least 6 7

8 themes and not necessarily with all the 11 themes of the framework, which comes to introduce flexibility in this existing building certification, making it easily adaptable to each residential rehabilitation project and specific target priorities, but effective in terms of defining minimum levels of performance improvement. Each of the eleven themes composing the technical reference framework is assessed according to a scale of 5 levels of increasing quality, knowing that: 3 is the minimum notation to be achieved by the 2 selected optional themes and by the 4 mandatory ones. 2 is the minimum notation to be achieved by all the other themes, taking into account that every non conformity (meaning the level C or D) detected during the diagnosis Bilan Patrimoine Habitat stage has to be corrected and brought at least to the regulation level. Figure 4 The 5 levels of the rating system of the certification Patrimoine Habitat & Environnement The certification process is composed of: A preliminary analyses made with the Bilan Patrimoine Habitat during the Pre Design Stage (Program) Un Audit: in pre design stage, for the verification of the environmental management requirements. Technical Assessments: carried out by an examiner, at 3 different phases of the Design Stage, in order to check conformity of the conception/design regarding the criteria of certification through a Preparatory study, a Provisional assessment and a final design assessment (and taking into account the considerations of the BPH). In Site Post Construction Verification: to check conformity of the executed works regarding the prescriptions and the characteristics assessed and approved during the Design stage and the design assessment stage. This is done at the end of the construction/rehabilitation stage. Every Project registered for certification is completely analysed in Design Stage and in Post Construction verification, by QUALITEL/CERQUAL Patrimoine s auditors and examiners so that conformity of the works and the new performances can be checked regarding what was defined during the Design Stage. The global certification process can be observed in Figure 5. 8

9 Figure 5 The Certification Process of Patrimoine Habitat & Environnement 4 THE RESULTS OF SUSTAINABLE CERTIFICATION OF RESIDENTIAL BUILDINGS REHABILITATION The Certification Patrimoine Habitat & Environnement (consistent with the HQE principles) was launched in 2006 by QUALITEL (through its subsidiary CERQUAL Patrimoine). This certification of existing residential buildings (and its rehabilitation) has responded to an increasing need and demand of the construction sector. Since its launching and until end 2009, more than homes registered and carried out a residential diagnosis Bilan Patrimoine Habitat ( of which in 2009). In addition, more than existing dwellings (designing rehabilitation works) have registered for certification Patrimoine Habitat or its environmental version Patrimoine Habitat & Environnement (34,136 of which in 2009). 5 CONCLUSION: The stock of dwelling in France is quite often old. Several million residences, of more than ten years old, present a strong potential of energy saving and comfort improvement. Based of these findings, the Group QUALITEL extended its certification activity to the quality and sustainability of existing homes. Thus in 2006 the certification Patrimoine Habitat & Environnement was launched, covering criteria related to comfort, economic and environmental performance, and technical quality, and being applicable to multi residential buildings (apartments), grouped houses, social or private promotions, in 9

10 single or joint ownership. This certification must be preceded by a preliminary global diagnosis (the Bilan Patrimoine Habitat), who informs the Building Owner on the main features of his building and can guide him in its environmental improvement and rehabilitation strategy. Patrimoine Habitat & Environnement was developed by QUALITEL jointly with the main and leading public and private experts and players of the residential sector. The environmental certification of Existing Homes of the Group QUALITEL is a voluntary initiative and a guarantee of the quality and performance of the rehabilitation project, whose building assessment is carried out by a totally independent third party (with no consultancy action in the overall process), which assures the credibility of the global engagements, and is guided by a consensual and rigorous reference framework. QUALITEL has been performing technical and/or environmental assessment for more than 35 years.the certification data analysed by QUALITEL, and kept confidential, allows the Association to observe, year after year, hundreds of rehabilitation projects and existing dwellings, which serves as sector information and experience feedback, particularly useful in this field; specially regarding existing residential building features, in a field where Regulation and technical rules are often inexistent or much less developed than the New residential sector. In parallel, a Data Monitoring and Building Observatories was created and financed by QUALITEL, in order to analyse current construction practices, which aims at organizing and compiling information about residential building characteristics, and to inform the Professionals about the real performance of the certified buildings. This dynamics also allows QUALITEL to keep up to date regarding the constructive and sustainable evolutions of residential market, to inform Public authorities and participate in Regulation working groups and definition, and also to continuously improve its certifications assessment schemes in order to keep promoting a sustainable transformation of market practices. For Residential Building Managers, the interest of this certification lies on its ability to evaluate in an objective way the conservation state of his residential asset, transparently proving the energy performance of the building, helping to develop a good patrimonial management and running costs control, but also informing and reassuring the final users/occupants regarding the quality of their habitat. For users, this certification is a way of optimizing the energy performance during the building in use stage, and it can help people to choose their home on the basis of reliable and certified criterion, sure of selecting a home that consumes less natural resources, that is operated in a more performing way and with upgraded levels of comfort and indoor environment quality. Information is also a key criteria of this existing building certification, in order for QUALITEL not only to participate to building environmental and technical quality but also to the change of occupants operating behaviours. In summary, the building certifications of QUALITEL are instruments of assessment and measure of the global technical and environmental quality of buildings. They evaluate the performance of the building in terms benefits for the final users, widely contributing for the improvement of the construction, through performance increase and through environmental awareness and information of those who intervene in the residential building: designers, builders, owners and occupants. 10