Traditional, state-of-the-art and future thermal building insulation materials and solutions – Properties, requirements and possibilities

Abstract

The advantages and disadvantages of the thermal building insulation materials and solutions have been treated. Both traditional, state-of-the-art and possible materials and solutions beyond these have been investigated. Examples of these may be mineral wool, expanded polystyrene, extruded polystyrene, polyurethane, vacuum insulation panels, gas insulation panels, aerogels, and future possibilities like vacuum insulation materials, nano insulation materials and dynamic insulation materials. Various properties, requirements and possibilities have been compared and studied. Among these are thermal conductivity, perforation vulnerability, building site adaptability and cuttability, mechanical strength, fire protection, fume emission during fire, robustness, climate ageing durability, resistance towards freezing/thawing cycles, water resistance, costs and environmental impact.Currently, there exist no single insulation material or solution capable of fulfilling all the requirements with respect to the most crucial properties. That is, for the buildings of today and the near future, several insulation materials and solutions are used and will have to be used depending on the exact circumstances and specifications. As of today, new materials and solutions like e.g. vacuum insulation panels are emerging, but only slowly introduced in the building sector partly due to their short track record. Therefore it will be of major importance to know the limitations and possibilities of all the insulation materials and solutions, i.e. their advantages and disadvantages. In this respect new conceptual thermal building insulation materials are also discussed.

Thermal conductivity of hygroscopic foams based on cellulose nanofibrils and a nonionic polyoxamer

“…3a). The thermal conductivity values measured for the isotropic CNF-and nonionic polyoxamerbased foam at low humidity (1.18 ± 0.1 g H 2 O/m 3 air, which corresponds to 5% RH at 299 K) range between 43 and 48 mW/mK, which correlates well with previous measurements of the thermal conductivity of cellulose and other biopolymer foams (Jelle 2011;Blomfeldt et al 2012;Lavoine and Bergström 2017).…”

“…Depending on the cellulose source and how the foams/ aerogels have been produced, the thermal conductivity of nanocellulose foams and aerogels varied between 20 and 40 mW/mK (Jelle 2011;Kobayashi et al 2014;Sakai et al 2016;Jimenez-Saelices et al 2017). To date, however, studies on the thermal conductivity of nanocellulose-based foams and aerogels are sparse and have primarily assessed the thermal conductivity of the porous materials at constant temperature and/or constant relative humidity (Silva et al 2010;Isogai et al 2011;Nguyen et al 2014;Wicklein et al 2014;Jimenez-Saelices et al 2017).…”

“…Biopolymer-based materials such as cork and wood chips were extensively used for thermal insulation prior to the introduction of fossil fuel-based foams, but their insulating performance is relatively poor (Jelle 2011). Nanocellulose features an attractive combination of properties like a high elastic modulus, low thermal expansion coefficient, and tunable surface chemistry (Klemm et al 2011;Moon et al 2011;Duong and Nguyen 2016).…”

Self-cleaning glazing products: A state-of-the-art review and future research pathways

“…Nonetheless, if the transmission is affected or not, a self-cleaning surface like the one presented in Figure 9, might be applicaple to fenestration products made of e.g. aerogel, which already is in use as semi-transparent or translucent walls and fasçades, or other application areas that does not require complete transparency as regular glass [3,28].…”

Energy efficiency in the Romanian residential building stock: A literature review

“…Their high thermal conductivity lead to very thick building elements in cold climate areas to be able to achieve the passive house and ZEB standard. The Polyurethane foam has the smallest thermal conductivity among the traditional thermal insulation materials, but it has the disadvantage of being very toxic in case of fire, because Polyurethane releases hydrogen cyanide [16]. Therefore designers try to find thermal insulating materials that have low thermal conductivity, do not allow air leakages, ensure thermal comfort and thermal stability and are not harmful to the indwellers' health.…”