Skip to main content

Development of innovative lightweight and highly insulating energy efficient components and associated enabling materials for cost-effective retrofitting and new construction of curtain wall facades

Periodic Reporting for period 3 - EENSULATE (Development of innovative lightweight and highly insulating energy efficient components and associated enabling materials for cost-effective retrofitting and new construction of curtain wall facades)

Reporting period: 2019-02-01 to 2021-05-31

The project idea comes from the fact that thousands of buildings in Europe have been constructed in the recent decades using curtain walls, i.e. facade modules which span from floor to ceiling, consisting of a transparent (vision glazing) and an opaque (spandrel) component to help hide features between the floors of a building.
Unitized systems were developed as a prefabrication strategy, driven by the intent to minimize expensive site labor, and to improve quality as provided by manufacture under factory controlled conditions. Improving energy consumption in the existing building stock requires the retrofitting of many curtain wall facades, responsible for up to 60% of energy losses through the envelope. This is a major concern because curtain wall technology has recently moved from office buildings to residential towers within the urban context. Replacement and retrofitting of curtain walls would allow an important enhancement in thermal performance. In this framework, EENSULATE project has the aim of developing a solution for envelope insulation to bring existing curtain wall buildings to “nearly zero energy” standards, reducing energy bills by while complying with the structural limits of the original building structure and national building codes.
To do so, the following main key enabling technologies were developed within the project:
1. Highly insulating foams to be used for the opaque part of the curtain wall modules (bi – component) and for the reduction of thermal bridges during installation (mono component)
2. A lightweight and thin double pane vacuum glass (VIG), to be used for the vision glazing part of curtain walls and for existing windows replacement, manufactured by means of a sealant with a distributed gettering technology
3. A multi-functional thermo-tunable coating based on novel moth-eye nanostructures, capable to control solar gains based on temperature and switchable from 20 to 70% G value
Based on these materials combinations, the project output is a family of insulating modules with different levels of performance and functionalities.
The EENSULATE façade modules and fenestration solutions have been installed in three real scale buildings as demonstration sites of the project (a school and a museum in Dzierżoniów and a public library in Pesaro) and data confirming the expected performance have been gathered.
A summary of the main project achievement is reported below.
• Definition of the requirements and drivers for the EENSULATE module in compliance with the current international regulations applied to curtain wall façade
• Definition of the specifications for the product development according to the quality certification
• Market analysis to assess the compliancy of the developed technology with the identified market drivers
• Development of highly insulating two components and mono-component foams for the manufacturing and insulation of the opaque components of curtain walls and for the reduction of thermal bridges
• Development of innovative sealant and getter for the manufacturing of Vacuum Insulated Glass (VIG)
• Accomplishment of small scale VIG prototype (500x500mm) having enhanced thermal performances and definition of the manufacturing process
• Development and refinement of the EENSULATE module design
• VIG manufacturing process scale up development and fine tuning
• Small and full scale VIG prototypes production for both testing and demo activities
• VIG prototype characterisation testing
• Manufacturing of the EENSULATE façade module (including TCF and VIG) for both testing and demo application
• Performance, Acoustic and Fire Mock Up testing
• Installation of the EENSULATE solutions in 3 demo buildings located in two different climates (Italy and Poland: Polish School, Polish Museum and Italian Public Library)
• Sustainability and replicability assessment of the proposed new solutions
• Validation of the energy performance of the developed products thanks to the pilots monitoring
• Consortium exploitation intentions definition, including IPR management
• Development of dedicated business models for the most promising project results according to the partners intentions and future plans
• Implementation of communication and dissemination strategies adapted to the unexpected scenario imposed by the Covid-19 emergency to ensure the duly visibility to the very promising project achievements
EENSULATE has been a highly multidisciplinary project aiming to optimise three core material innovations and their integration in an innovative envelope component, enabling a reduction by almost 50% of the U value and a weight reduction by 35%. The sustainability is ensured by reduced temperature for glass sealing and environmental friendly foam formulation, reduction of material use for the glazing component and spandrel insulation as well as downsizing of sub-structures. The reduced weight impacts in particular on the structural requirements for high rise buildings, optimising the use of concrete and/or steel and associated embodied energy.

The application of the innovative EENSULATE products has been tested in two different climate conditions (southern Europe – Italy and norther Europe – Poland) and in different application scenarios (historical windows, curtain wall facades) and they have been compared with different benchmark products (i.e. single glass panes, double-glazing units, triple-glazing units, mineral wool).

Considering a 20 years life cycle, from manufacturing until use phase of the targeted products, EENSULATE solutions showed lower environmental impacts in almost all of the Environmental Footprint impact categories. Such improvements are linked to the relevant savings foreseen in the use phase (because of the significantly lower U-value of the VIG compared with the benchmark), and to the savings obtained in the VIG manufacturing phase if compared with the benchmarks (i.e. DGU and TGU). The EENSULATE façade module appears as the most promising application towards benchmark products based on TGU and mineral wool. Although foam manufacturing entails higher costs than mineral wool production, VIG production process guarantees relevant savings if compared with the manufacturing of TGU.
For all case studies, the main differences between EENSULATE and benchmark products are based on the manufacturing and the use phase: indeed, assembly and installation essentially consist of the same raw materials and procedures; however, the EENSULATE solution is actually lighter than the benchmark one, thus potentially allowing an easier installation process entailing the use of more lightweight or lower number of additional components like brackets, anchorages, etc.
Considering the better technical performances given by the increased thermal and acoustic insulation, the lower environmental impacts for most of the impact categories and the high potential for further improvements aiming to reduce costs of the developed processes, the EENSULATE solutions show a significant potential for a real market deployment and wide replicability. This aspect is particularly proved by the different types of application, typology of buildings and climate scenarios analysed within the project: the EENSULATE solutions show a high versatility, with promising results especially from an environmental sustainability perspective.