• Energy Research

Abstract New policies on energy efficiency in buildings aim to improve our environment. EU requirements on reduced energy demand to achieve Nearly Zero Energy Buildings are of equal importance to pollution and raw-material consumption. Addressing these parameters, building life-cycle analyses are needed, not only to reduce energy consumption, but also to encourage the use of renewable materials. Other priorities are building maintenance and construction material management at the end of the useful life of the building. The use of wooden facades is not very common in Spain. In this study, its energy efficiency is assessed against Spanish Government Regulations, through the Building Technical Code. Hence, this analysis of wooden facades examines their influence on the thermal behavior of the whole building, considering both material properties and structural design, focused on the exterior cladding or protective layer. These structures imply an optimized assembly design together with the application of a protective treatment, depending on its natural durability. “Radiata pine” was selected as one of the most common pine species in the Basque Country, suitable for cladding and grown in sustainable forestry programs. Several commercial simulation tools were used, such as: Therm, Wufi, and DesignBuilder aiming to a full thermal characterization of these particular enclosures, whereas the results obtained were finally validated through an experimental facility.

The increasing energy consumption levels of buildings within Europe call for controlled consumption and improvements to energy savings and efficiency and effective energy efficiency regulations. However, many aging and energy-inefficient buildings require energetic retrofitting that can employ various façades solutions and insulation materials. The selection of the most sustainable options in each situation therefore requires a decision-making methodology that can be used to prioritize available retrofit solutions based on economic, functional, environmental and social criteria. In this paper, both the methodology and the economic basis of the retrofitting process are presented. The methodology was validated in a case study, and a sensitivity analysis also demonstrated its validity, robustness and stability