Skip to main content

Robust Internal Thermal Insulation of Historic Buildings

Periodic Reporting for period 2 - RIBuild (Robust Internal Thermal Insulation of Historic Buildings)

Reporting period: 2016-07-01 to 2017-12-31

RIBuild (Robust Internal Thermal Insulation of Historic Buildings) is an EU research project that develops comprehensive guidelines on how to install internal thermal insulation in historic buildings with facades of briskcwork or natural stone, maintaining their architectural and cultural heritage.

Energy consumption in historic buildings needs to be reduced to meet the EU 2020 climate and energy targets as they account for more than a third of the total energy consumption of buildings in the EU. Reducing the energy consumption by installing thermal insulation at the external walls will also reduce draft close to the external walls as these often are poorly insulated. The potential for energy savings in historic buildings related to internal insulation is 15-20 %. Building owners and practitioners in the construction industry need knowledge and guidelines on how to handle internal thermal insulation in historic buildings in an effective and secure way.

RIBuild investigates how and under what conditions internal thermal insulation can be employed. Research activities include on-site case studies as well as simulations and laboratory measurements of materials.
The guidelines on how to install internal insulations in historic buildings aim to help authorities, building owners and professional practitioners within the EU building sector. A number of guidelines will be developed. e.g.:
• Guidelines for determining whether a building is suitable for internal insulation or not
• Guidelines for a standardised simulation and testing methodology
• Guidelines with a catalogue of possible solutions depending on the construction type, climate etc.
• Guidelines for evaluating the energy saving potential and the environment impact
In the first 36 months the project consortium has activated all work packages, and has met seven times (bi-annual) to coordinate the project and to discuss cross-linking issues. Participants in the different WPs met to discuss more specific items relating to content and progress of the WPs.

WP1 produced two deliverables. D1.1 is based on a screening on the existing building stock and examples of renovation of historic buildings carried out. D1.2 is based on a literature survey on existing insulation materials and methods for application in historic buildings, and decision tools for implementation of internal insulation in historic buildings.

WP2, WP3, WP4 and WP5 all have finished their first deliverable. The major aim of D2.1 (WP2) was to determine the most decisive hygrothermal material properties to help a user to focus on which material properties to test in a specific case. However, it was not possible to single out such properties as the decisiveness of properties e.g. depends on which failure mode is considered. Further, D2.1 presents common simulation tools available for hygrothermal simulation and includes a compilation of material properties for historic building materials and internal insulation materials. Finally, methods to determine material properties are presented.

D3.1 (WP3) describes laboratory test stands involving internally insulated wall samples with embedded joist end constructions (Germany, Denmark, Belgium). The tests aim to derive general conclusions about the performance of different insulation systems in comparison with each other. Furthermore, they offer valuable data sets for the validation of software tools.

D4.1 is about probabilistic assessment of interior insulation solutions. The effectiveness and efficiency of the Delphin hygrothermal simulation program has been improved and different approaches on how to perform probabilistic assessment more efficiently are analysed.

D5.1 presents the methodology and software tool developed within RIBuild for probabilistic Life Cycle Impact Assessment of the environmental impact of internal insulation solutions. Further, it reports results of analyses on the potential energy savings in historic buildings when considering internal facade insulation.

In WP6 guidelines are developed based on the work within WP1-WP5 accompanied by a web tool targeted at professionals in the building sector. The web tool will be based on precalculated examples as online calculation of a specific building will be too time-consuming even with the improvements made in WP4.

WP7 takes care of communication and dissemination and has established an external and internal website. 56 organisations from 9 European countries have signed up as network partners. A seminar was held to discuss the need and potential as well as the risks of internal insulation. A survey further explored the challenges practitioners experience when using internal insulation and gained ideas for RIBuild guidelines. It shows a lack of knowledge about and skepticism towards using internal insulation, underlining the necessity of RIBuild. Further, the target group prefers a digital tool, supporting the choice of making an online tool.

Three meetings has been held with the External Expert Advisory Board, giving valuable input to the contents and goals of the project. Specific collaboration with other EU research projects has been low, apart from being present at a couple of closing conferences, because of limited feedback from other projects when contacted. RIBuild has been represented at a number of international conferences, and journal papers, radio interviews etc. are also used as a way to communicate results and to spread knowledge about RIBuild.
RIBuild focuses on these aspects concerning state-of-the-art: Application of internal insulation, and probabilistic modelling in a building physics and an environmental domain.
Application of internal insulation in existing buildings is limited, primarily related to lack of knowledge (suitable measures, requirements to the existing wall, installing the insulation). Systematic gathering of data on material, component and building level (incl. typical wall constructions and different types of internal insulation systems) takes place in RIBuild. Studies on the effect of impregnating the façade are ongoing. Combined with development of probabilistic modelling described below, it should be possible to broaden the results achieved at material, component and building level to other materials, constructions and locations.

A methodology for probabilistic assessment of hygrothermal simulation under development makes it possible to take into regard uncertainties related to properties of historic building materials when simulating an internal insulated wall. The first deliverable (D4.1) shows that it is possible to reduce the computing time markedly making a probabilistic assessment much more feasible than today.

In parallel, a methodology for probabilistic life cycle assessment was published (D5.1) together with a web tool. Present methods based on a deterministic approach not sufficient to correct assess variations in energy use and environmental impact.

RIBuild partners have been present at international conferences and seminars, and have made contacts to other research projects within renovation of buildings. Further, a network of organizations was established within partner countries. At present, it is difficult to estimate the specific impact of these activities; communication with both the building sector and the international academics takes time before it is having an effect, eventually changing the behavior concerning performing internal insulation.
Picture of our Italian case building
Picture of our Swiss case building
Picture of our EEAB taken in Leuven on 16 November 2017.
Picture of our Latvian case building