Abstract
Two renovation strategies were considered and compared in this paper for the energy renovation of social housing in condo buildings built in 1945–1969, situated in residential estates that have been declared urban areas of interest. One of the strategies, named here the image conservation approach, consists of renovating the building with very efficient solutions, except for the brick-facing walls, which will only have insulation in the existing cavities. The other strategy, the image coordination approach, consists of renovating the whole building with efficient solutions, including external insulation for existing brick-facing walls, and drawing up coordination plans for each of the residential estates in order to guarantee a coordinated new image of the residential estates. By means of three case studies in the city of Zaragoza and four scenarios of improvement, the two strategies are compared regarding the regulation compliance, the energy use, the emissions reduction, the thermal comfort, and the cost-effectiveness of the measures. The results show that the image coordination approach is the best strategy in regard to the studied aspects, achieving a 69%–79% reduction of CO2 emissions and a 75%–97% reduction of heating use, as well as being the only one capable of transforming these buildings into nearly zero energy buildings (nZEBs).
Highlights
The European Union (EU) has set targets for reducing its greenhouse gas emissions progressively up to 2050 by means of the 2020 climate and energy package, the 2030 climate and energy framework, and the 2050 long-term strategy [1]
The results show that the image coordination approach is the best strategy in regard to the studied aspects, achieving a 69%–79% reduction of CO2 emissions and a 75%–97% reduction of heating use, as well as being the only one capable of transforming these buildings into nearly zero energy buildings
One of the scenarios complied with the nearly zero energy buildings (nZEBs) renovation requirements, scenario 4, and two of the scenarios, scenarios 2 and 4, complied with the major renovation requirements (Table 3)
Summary
The European Union (EU) has set targets for reducing its greenhouse gas emissions progressively up to 2050 by means of the 2020 climate and energy package, the 2030 climate and energy framework, and the 2050 long-term strategy [1]. The public administrations in Spain started to promote an energy retrofit of social housing estates built in the mentioned period about fifteen years ago This is the case, for example, of the city of Zaragoza, where 19 multifamily social housing estates (including 7981 dwellings [7]) started being studied in 2004 (together with another two residential estates of single-family houses) [8] and demonstrative building renovation projects were developed in four of these estates in 2008–2011 [9]. One of the options is to use image conservation-oriented energy retrofit strategies that do not compromise the façades image, as in the case of the Brunswick Centre in London [17], but without using inside insulation so that the usable floor area remains equal after the intervention This implies energy improvement of roofs, windows, plastered walls, and existing wall cavities. The scientific contribution of this paper is in the field of design research [23,24], and focuses on the improvement of the observed phenomenon in architectural design of dealing with the tensions between the sustainability goals and the preservation of the modern built heritage
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
