Development of prefabricated retrofit module towards nearly zero energy buildings

The building sector is an energy intensive sector, with great potential to reduce energy needs and environmental pollution. Several measures are being taken to increase the energy efficiency and avoid energy consumption in this sector. A recent trend is the nearly zero energy buildings, which was already adopted by some of the latest regulations, such as the 2010 recast of the European Performance of Buildings Directive (EPBD). However, to reach these goals, especially considering the existing building stock, new retrofit solutions are required, which must be well adapted to the specific building stock needs, and ensure that the building retrofit can achieve the nearly zero energy buildings standards. This paper presents a new prefabricated retrofit module solution for the facades of existing buildings, and also the steps taken to optimise its performance, which includes a judicious choice of materials, 3D modelling, cost–benefit analysis, use of different simulation tools for performance optimisation and prototyping. It is also shown the implementation of the retrofit module within an integrated retrofit approach, whose final goal was to obtain a building with the minimum possible energy consumption and greenhouse gas emissions.

► Prefabricated retrofit module PRM for building facades to increase energy efficiency.
► Energy performance and thermal bridges evaluated by dynamic simulation tools.
► Detailed monitoring of the thermal performance of PRM module prototypes.
► Application of PRM to test building resulted on a reduction of energy needs up to 16%.
► Simulation of an integrated retrofit procedure with PRM, reached NZEB standards.