Vast numbers of uninsulated buildings still exist in Europe, and up to 35 % of the heat loss of a building is caused by uninsulated walls. New insulating products and systems are necessary both for thermal renovation and in the creation of new buildings. The EU-funded Wall-ACE project has been designing a walling system of complementary tools that use nanomaterials for efficient insulation. “Wall-ACE closes the scientific gap between the demand for new advanced insulation products and systems to meet the requirements of the Energy performance set by the Building Directive (2010/31/EU) and the market situation,” says Tina Oertel, Head of Development for Render Systems at Sievert (which until January 2020 was Quick-mix Putztechnik) and Wall-ACE project coordinator. The project had several key initiatives, beyond reducing energy consumption and CO2 emissions, including: the development of energy-efficient mineral-based materials; improving indoor air quality; raising the durability and sustainability of European buildings; and creating solutions that are both affordable and easily replicable across European states. All products and systems were tested at building scales, in real conditions, and the Wall-ACE project also assessed the most viable routes to market, along with certification and standardisation of these highly efficient new systems. The thermal performance targets were met for all five new products included in the walls, proven by product properties and partly proven in practice. Real-world testing of the new walling designs shows an improvement in insulation properties of at least 25 % in various components, with a 15 % improvement for bricks.
Ace wall innovations
The new walling system is known as a High-performance Optimised Nanomaterial Energy efficient SysTem (HONEST). The suite of technologies included are insulating thermal coating-finishing, internal high-performance insulating plaster, insulating interior patching filler, external high-performance insulating render, and insulation clay bricks. “Beyond expectations, the thermal coating finishing increases the thermal indoor comfort,” adds Oertel. All developments contain nanotechnology-based Kwark © silica-aerogel. They are all almost completely mineral and therefore especially fire-resistant and permeable to water vapour. This permeability lets the walls breathe, as water vapor can be absorbed and transported through the walls. This has a positive impact on indoor air comfort in comparison to ‘non-breathable’ plastic-based products. The insulating materials help to reduce energy consumption throughout buildings, while insulating layers can be applied at varying thicknesses. This is a particular advantage when renovating historical listed buildings, which are critical to preserve for European cultural longevity and were likely created without energy efficiency in mind.
Building the future
The walls were tested at different demonstration sites in France, Italy, Switzerland and the UK to demonstrate the feasibility of in situ installation under various climate conditions and to allow on-site measurements. “The monitoring of products under aging conditions gave advice for further improvements,” adds Oertel. The Wall-ACE products have a high replication potential in both new construction and renovation in Europe, and all materials and systems can be used for domestic and for non-domestic buildings either individually or as a fully complementary system. “The most important aspect of having the products as a system is that the compatibility of the products with each other has been tested and verified through the project,” Oertel concludes.
Wall-ACE, wall, construction, insulation, efficient, air quality, nanotechnology, heat loss, complementary