Nachhaltige Erneuerung historisch wertvoller Bauten

• Forschungsstelle: BFE
• Projektnummer: 103139

Schlüsselwörter (Deutsch)

TP0083;F-Gebäude

Kurzbeschreibung (Deutsch)

Nachhaltige Erneuerung historisch wertvoller Bauten

Publikationen / Ergebnisse (Englisch)

The CCEM SuRHiB project was started July 2009 with support of the Swiss Federal Office of Energy. Additional funding for industrial cooperation was given by the Swiss Innovation fund CTI. The CCEM project is running till November 2012. Most energy conservation measures have been developed for past war building constructions, which are aesthetically not so sensitive. The refurbishment of traditional buildings and especially for monument preservation is requiring adapted approaches for thermal improvement of the building envelope. The aim of this project is the development energy renovation methods that are focussed on the needs of old buildings from end 19th to beginning 20th century. Renovation measures that are energy efficient and suitable for the renovation of such buildings are evaluated and further developed. Various sub-projects are therefore studying new material options and envelope concepts using the latest advances in materials technology and hygrothermal simulation are used to improve the energy efficiency and to lower the moisture damage risk. A highly insulating rendering and well tested internal insulation systems will be main results of the project. During 2011 the hygro-thermal simulation of traditional wall constructions has been approved and the weathering tests for internal insulation systems have been started. The measurements will allow a better understanding of moisture transfer in rain exposed walls and provide design guidance for low risk internal insulation systems. Full size tests have been done with the highly insulation aerogel rendering. The difficulties that occurred during spray application have been solved. The innovation made to overcome this problem is registered for patenting.

Auftragnehmer/Contractant/Contraente/Contractor:
EMPA

Autorschaft/Auteurs/Autori/Authors:
Carmeliet,Jan
Zimmermann,Mark

Schlussbericht (Deutsch)

Im Rahmen dieser Forschungsarbeit wird die Funktionsfähigkeit des Feuchteschutzes historischer Aussenwänden mit Innendämmsystemen untersucht. Hierfür werden zunächst die feuchtetechnischen Eigenschaften historischer Backsteinsorten analysiert. Die feuchtetechnische Funktionsfähigkeit der Innendämmsysteme wird dann mittels hygrothermischer Bauteilsimulationen mit dem Programm WUFI® überprüft. Diese Simulationen werden für Innendämmsysteme mit den Wärmedämmstoffen Steinwolle, Glas-wolle, Holzfaserdämmung, Zellulose und Schaumglas durchgeführt. Für die Analyse werden realitätsnahe, langfristige klimatische Randbedingungen des Standorts Zürich benutzt. Die so berechneten Wassergehalte in den Schichten werden mit den Versagenskriterien der einzelnen Bauteilschichten, wie der Frostsicherheit des Backsteins, dem Risiko von Schimmelpilzbildung oder der Feuchte-schäden bei Holzwerkstoffen im Dämmsystem beurteilt. Als Ergebnis der Simulationen werden die Eigenschaften der Bestandswand, die für die langfristige Funktionsfähigkeit des Innendämmsystems erforderlich sind, identifiziert. Der Wärmeschutz der typischen Wärmebrücken an Rändern und Durchdringungen von Innendämmsystemen wird berechnet. Die Ergebnisse zur Beurteilung des Wärmeschutzes der Wärmebrücken werden in Form von fRsi- und Ψ -Werten in einem Wärmebrückenkatalog zusammengefasst. Aus den Simulationsergebnissen werden Planungshinweise für Planer und Ausführende entwickelt und in einem Katalog zusammengestellt.

Zugehörige Dokumente

• Nachhaltige Erneuerung historisch wertvoller Bauten Arbeitspaket 5: Innenliegende Wärmedämmung - Schlussbericht mit Anhang [PDF] 50'709 kB
• Nachhaltige Erneuerung historisch wertvoller Bauten Arbeitspaket 5: Innenliegende Wärmedämmung - Schlussbericht [PDF] 4'706 kB

Schlussbericht (Englisch)

The CCEM-SuRHiB project was started 2009 in order to improve renovation technologies for sustainable renovation of traditional buildings. The focus was on traditional buildings that have been built at the end of the 19th or at the beginning of the 20st century. It was obvious that such buildings require adapted renovation measures that do not harm the original architecture and workmanship of these buildings.    .  Historical buildings count for about 20 % of the existing building stock. Many of them are not protected buildings but they are characterizing the centres and history of European cities and are part of our cultural heritage. However, these buildings, if normally heated, cause relatively high energy consumption. Without improving the energy efficiency of historical buildings, this part of our building stock providing 20 % of heated space could become responsible for about 60 % of the thermal energy demand of the total building stock assuming, the other buildings will be retrofitted.
 
Due to the fact, that the façades of historical buildings should be conserved, the thermal insulation of these buildings becomes difficult and risky. The moisture balance of walls has to be carefully considered besides the energy balance and a careful risk assessment related to heat and moisture transfer has to be done. The work was done based on a survey of monument preservation requirements and climate load assessment.
 
The aim was to understand the hygro-thermal behaviour of historical buildings and to develop renovation technologies that allow reducing energy consumption and protecting the cultural qualities of such buildings. The investigations included the analysis of traditional construction technologies and materials and the challenges due to climate change. The expected impact of temperature increase and driving rain has been simulated by combined heat and moisture simulations.
 
Especially the hygro-thermal behaviour of internal insulation has been studied because it will not only reduce thermal losses, it will also hinder the drying process of walls. Accumulated moisture could destroy valuable historic façades within short time. A careful risk assessment and robust guidelines has been developed. 
 
As another, less risky option a highly insulating light weight plaster rendering has been developed that insulates better than polystyrene foam but is based on mineral materials and is open for moisture diffusion. The development of this new building material is based on aerogel particles. It allows a thermal conductivity of less than 30 mW/(m·K) and can be applied inside and outside of a façade wall. The technology development was focussed on a novel type of highly insulation rendering and optimized solutions for internal insulation systems. The technology development has successfully been completed. Several demonstration projects have been insulated with the new type of rendering that is be available on the Swiss market since 2013. 
 
In addition it has been studied how damage risks can be minimized by indoor climate control and guidelines have been developed for the application of solar energy collectors in historical environments. Finally, historic buildings will not become zero energy buildings, but will be reasonably energy efficient to operated and maintained in the future.

Zugehörige Dokumente

• Sustainable Renovation of Historical Buildings (SuRHiB) | Nachhaltige Erneuerung historisch wertvoller Bauten - Final Report [PDF] 1'032 kB