Energy performance in heritage buildings
The Ministry of Culture is committed to reconciling heritage conservation with energy performance and even energy efficiency objectives. In this context, studying the intrinsic qualities of a building of heritage interest is essential before any recommendation of work.
Avoid work of a systematic nature
The search for energy savings must avoid leading to systematic work resulting in irremediable modification of facades by installing insulation from the outside, the replacement of all windows and old joinery and the dispersion of solar panels on the roof, without taking into account the heritage and landscape interest of the built heritage.
Aware of the risk of trivialization and disappearance of a large part of the built heritage, architects and specialized companies now offer interventions that seek to optimally reconcile the objectives of energy performance and preservation of heritage and the built environment.
Focus on sustainable interventions
This specific and sustainable approach is reflected in the desire to preserve what makes up most of the building, to highlight the intrinsic qualities of the building and to replace or recycle a maximum of materials. This approach combines in-depth study of the building (inertia, ventilation), detection of thermal bridges, search for innovative solutions from the technical point of view, use of sustainable and risk-free materials and products for the long-term conservation of structures, the second work and the architectural decorations.
It is a question, through appropriate studies, of finding pragmatic solutions adapted to each building of heritage interest.
A European methodology standard to assist evaluation
Action has been taken to this end within the framework of the production of specific European standards adapted to the conservation of cultural heritage.
Thus, in June 2017 was published the NF EN 16 883 standard - Energy performance of heritage buildings.
This European standard, designed by heritage practitioners and professionals, provides guidelines to sustainably improve the energy performance of buildings with historical, architectural or cultural value, while respecting their heritage interest. It advocates a working procedure for the choice of measures, based on the investigation, analysis and documentation of the building and on the assessment of the impact of these measures in relation to the preservation of the characteristic elements of the building.
Each heritage building must be considered as a special case. The heritage value of the building must be carefully assessed in terms of its regional, national and even international cultural context. Understanding the authenticity, integrity and heritage value of the building defines the characteristic elements that must be preserved.
The recommended measures must comply with the principles of conservation of buildings defined in international charters and regulations.
Maintain above all
The standard also reminds us that the best conservation measure is the proper maintenance of the heritage building. Any improvement measures therefore facilitate the continuous maintenance of the building and any added elements and materials.
Respect features
Any intervention carried out on a building of heritage interest must respect its characteristic elements, which may take the form of spatial configurations, appearance, construction structure and technical systems of the building. Any measure leading to an alteration of these elements should be avoided. Interventions must be additive and, as far as possible, non-invasive and reversible in order to minimize their impact on the heritage interest.
It is particularly recommended that the choice of stakeholders (architects, design offices, diagnosticians, auditors, companies) take into account their training, qualification and experience in working on heritage buildings.
The experimental label Effinergie Patrimoine
Launched in September 2019 for an experimental phase of two years (extended by one year), this label is carried by the collective Effinergy (association law 1901) and received the support of the Ministry of Culture.
The experimental label Effinergie Patrimoine is aimed at project owners undertaking energy rehabilitation works on buildings of heritage interest, including buildings classified or registered as historic monuments.
The label puts forward a triple objective: works at the low consumption level, interventions engaging the preservation of the built heritage, an improvement of the quality of life in these buildings.
Regulations that take into account technical, architectural or heritage constraints
In 2022, in application of the Climate and Resilience Act, the regulations relating to regulatory energy audits provided for in L. 126-28-1 of the Building and Housing Code takes into account the «technical, architectural or heritage constraints» and the proposed works «must be compatible with the easements provided for by the heritage code».
- Decree No. 2022-780 of 4 May 2022 on energy audit mentioned in Article L. 126-28-1 of the Construction and Housing Code
This decree, made under theArticle 158 of the Climate and Resilience Act, which provides for the obligation of an energy audit for the sale of the lowest-performing single-property dwellings, specifies the qualifications and skills of the professionals who carry out these energy audits.
Article 2 of the decree provides, in particular, that "where technical, architectural or heritage constraints or the cost of the work impede the attainment of class B within the meaning of the article L. 173-1-1 of the Building and Housing Code, the auditor justifies this in his report.” - Order of 4 May 2022 defining for metropolitan France the content of the regulatory energy audit provided for in Article L. 126-28-1 of the Construction and Housing Code
In particular, thearticle 2 of this order recalls that the proposals for work in the context of the energy audit must be compatible with easements under the Heritage Code ".
TheArticle 3 specifies, by way of derogation, the energy performance class to be achieved in the case of technical, architectural or heritage features and provides that “The six work stations shall be considered to have been treated if the auditor certifies that they have been upgraded to a high level of performance using the best available techniques and compatible with the characteristics of the building concerned.”
TheArticle 4 provides that the summary report drawn up during the audit shall include in particular the justification of technical, architectural or heritage characteristics.
Exceptions to the criteria of efficient energy renovation:
Article R. 112-18 of the Construction and Housing Code
Buildings falling within the exception provided for in the fifth paragraph of 17° bis of theArticle L. 111-1 of the Construction and Housing Code are those for which effective renovation work:
1) Would result in changes in the condition of the exterior parts or elements of architecture and decoration of the construction, contrary to the rules and requirements provided for:
a) Listed or listed historic monuments, remarkable heritage sites or the surroundings of historic monuments mentioned in Book VI of the Heritage Code;
b) The building or architectural ensemble having received the label mentioned in article L. 650-1 of the Heritage Code;
c) Sites listed or classified in Chapter I of Title IV of Book III of the Environment Code;
d) Constructions, pursuant to the provisions of the by-law of the applicable land use plan taken on the basis of Articles L. 151-18 and L. 151-19 of the Planning Code, and relating to the exterior appearance of the structures and the conditions of alignment on the road and minimum distance from the separative boundary and the layout of their surroundings, subject to the right of overhang for thermal insulation from the outside provided for in Article L. 113-5-1 of the Construction and Housing Code;
2° Exceed 50% of the market value of the property, assessed by a professional in the field of real estate;
3) Could pose a risk of building pathology, affecting in particular the structures or the covered enclosure of the building. This risk is justified by a reasoned note written by a man of art, under his responsibility;
4) Would not comply with any other obligations relating, in particular, to soil law, the right of ownership, the security of property and people or the appearance of facades and their location.
Energy performance diagnosis
Historic monuments classified or listed under the Heritage Code are not subject to the provisions on energy performance diagnosis pursuant to e) of Article R. 126-15 of the Construction and Housing Code.
Refer to:
- The documentary offer of the resource center for the responsible rehabilitation of old buildings [CREBA]
- Thermal improvement of old buildings [ATHEBA] of Maisons Paysannes de France
- The guide for the rehabilitation of buildings in the town center: Adapting old buildings to climate issues (DRAC Bourgogne-Franche-Comté)
Partager la page