The enhancement of energy performance of buildings has become a pillar of energy policies. The main target is the cut of energy consumption to reduce buildings footprint. This aim is pursued by introducing constrains on building requirements in terms of properties of basic materials and components and exploitation of renewable energy sources . That results in the definition of the zero-energy building (ZEB) concept. The new paradigm introduced new challenges and, at the same time, involved all the different stakeholders in facing the barriers to the diffusion of the novel solutions proposed by the research development. This paper summarizes the actual state-of-art of whole performance of ZEBs and the related technical solutions, analysing their increasing potential in energy consumption. A collection of the different case studies reported in literature involving ZEBs is presented, compiling an analysis of the performance of the common solutions actually applied. The technologies involved are described discussing their impact in meeting the ZEB requirements. A debate is proposed, pointing out the main aspects deserving further investigations and outlining the critical elements in making the zero-energy target the new standard for the buildings.

A review of performance of zero energy buildings and energy efficiency solutions

A review of structural, thermo-physical, acoustical, and environmental properties of wooden materials for building applications

Resource efficiency in industrialized housing construction – A systematic review of current performance and future opportunities

Prefabricated buildings recently became more prominent providing significant benefits including contribution to emission reductions at scale and the manufacturing of building components to high accuracy. However, in China, the proportion of prefabrication is lower than that in many developed countries. The prefabricated wall is one of the most important precast elements and its thermal performance has significant impacts on buildings' energy consumption and environmental performance. This work reviews the thermal performance of prefabricated walls encompassing survey of two common structures, precast concrete sandwich walls and lightweight steel-framed walls. The applicability and limitations of methods frequently used to determine the thermal resistances of these two walls are presented. This article also shows a literature review on the implications of prefabricated buildings to China's emission reductions. Compared to conventional buildings, the contribution of prefabricated buildings on China's emission reduction has been recognized. The potentials on building energy efficient and waste minimisation were also acknowledged. It is concluded that the prefabrication has been generally considered to be a more sustainable method in building sector. The energy-saving potential of prefabrication was demonstrated based on life cycle analysis and thermal performance evaluation. It was found the thermal performance of buildings has multiplied by adopting prefabricated facade elements for building retrofitting. More studies related to thermal performance of prefabricated walls with different structures shall be covered in future research. It is also suggested to develop a more representative result of energy performance by adopting prefabrication, with all dimensions of prefabricated buildings' feature considered.

Review of thermal and environmental performance of prefabricated buildings: Implications to emission reductions in China

Building renovation with prefabricated ventilated façade element: A case study

The nearly zero energy buildings (nZEB) ideology of the future obliges, first and foremost, that heat losses should be reduced remarkably compared to the present levels. The current study examines the potential hygrothermal risks and their effect on highly insulated timber frame exterior walls under cold climate conditions. The focus is on the timber frame exterior walls with thermal transmittances between 0.17 and 0.08 W/(m 2  K), with different material combinations and boundary conditions, where the risk of mould growth as a performance criterion was used. A careful selection of materials allows to design moisture safe timber frame exterior walls and provide low thermal transmittance. It was found that the relative humidity and the risk of mould growth are higher and the drying out period is longer in walls with lower thermal transmittance when insulation thickness is the only changed parameter. Wind barriers with higher thermal resistance and water vapour permeability indicated a lower increase of mould growth risk in structure in the course of reduction of the thermal transmittance. Therefore, the building envelope of the future nZEB needs a careful hygrothermal design.

The effect of thermal transmittance of building envelope and material selection of wind barrier on moisture safety of timber frame exterior wall

Hygrothermal Performance of Highly Insulated Timber-frame External Wall☆

nZEB Renovation with Prefabricated Modular Panels

Influence of Moisture Dry-out on Hygrothermal Performance of Prefabricated Modular Renovation Elements

An improvement in energy performance for existing buildings is needed to fulfil EU energy policy. The efficient way to accomplish the idea of nearly-zero energy buildings (nZEB) is to apply the int...

Peep Pihelo

Papers

The effect of thermal transmittance of building envelope and material selection of wind barrier on moisture safety of timber frame exterior wall

Hygrothermal Performance of Highly Insulated Timber-frame External Wall☆

nZEB Renovation with Prefabricated Modular Panels

Influence of Moisture Dry-out on Hygrothermal Performance of Prefabricated Modular Renovation Elements

Commissioning of moisture safety of nZEB renovation with prefabricated timber frame insulation wall elements