Sustainability assessment of refurbishment vs. new constructions by means of LCA and durability-based estimations of buildings lifespans: A new approach

Abstract

A common practice in Life Cycle Assessment (LCA) of buildings is to consider a default value for their lifespan. This paper addresses the importance of estimating the lifespan of each evaluated building when refurbishment and new construction are compared, using a case study. The lifespans of the refurbished and the new buildings are estimated by applying degradation models of reinforced concrete structures. A simplified economic analysis is also performed. Two thermal performance levels are evaluated: standard and passive, in both alternatives, the refurbished and the new building. Results show that a new building can have a lifespan more than six times longer than a refurbished one. Passive refurbishment appears to be the best choice from an environmental point of view. Even if a new passive building obtains slightly better results, these can only be ensured if it is in use for a long period, in our case 210 years. This is not easy to guarantee in real practice, according to usual trends. The new passive building results to be the most cost-effective, but the same constraints regarding guaranteeing a long lifespan are applicable. The results reveal a strong dependence of LCA results on the lifespan. Its value can alter the order of preference of the solutions when comparing alternatives. There is a high potential of environmental improvement of buildings behavior by changing current practices and extending buildings' lifespan up to their physical limit.

Energy Retrofit of Social Housing with Cultural Value in Spain: Analysis of Strategies Conserving the Original Image vs. Coordinating Its Modification

“…The majority of the building floor area in Spain is composed of residential buildings (82.67% in 2013) [3]. Since the existing residential buildings at present will represent the major part of the housing stocks of Spanish cities in 2050 [4,5], energy retrofit has become one of the most important strategies for the decarbonization of the residential sector. The European Directive 2010/31/EU on Energy Efficiency in Buildings introduced the need to transform buildings into nearly zero energy (nZEB) by 2050, and the European Directive 2018/844/EU amended the existing Directive 2010/31/EU in order to accelerate the decarbonization of the parks in the EU.…”

“…The tensions and conflicts between the sustainability goals and the preservation of the modern built heritage have broadly been addressed in the literature [14][15][16][17][18][19][20][21]. Some authors took a stand against the demolition of old housing buildings, arguing that important synergies can be found between sustainability and conservation, e.g., [4,5,18,21]. Other authors focused on the design challenge of finding an architectural balance between existing and newly added qualities when designing the renovation of housing blocks with specific architectural heritage values, e.g., [14,15,19,20].…”

Comprehensive Sustainability Assessment of Regenerative Actions on the Thermal Envelope of Obsolete Buildings under Climate Change Perspective

“…Addressing the issue of the RSP and the useful life of the property, it is convenient to argue the considerations made. Palacios-Muñoz [42] points out that the lifespan is a key aspect for the results of any LCA, since the results are closely related to that period of time. However, there is no clear consensus regarding what this period is.…”

Evaluation of Life-Cycle Assessment Analysis: Application to Restoration Projects and New Construction in Alpine Climate, Japan

“…However, the reliable application of LCA to conservation practice requires further investigation and practice [40][41][42]. Results may be influenced by the considered lifespan, databases, system boundaries and reference study period [43][44][45][46]. The choice of indicators must be based on the well-defined objectives of LCA [47].…”