Precost&E Rehabilitation

Evaluation of construction costs and energy consumption resulting from energy rehabilitation of an existing residential building in D3 climate zone (Madrid).

Precost&E Rehabilitación

Theoretical study that analyzes the relationship between the actions needed for energy rehabilitation from a residential building in Madrid, its costs and the improvement of energy rating. The aim is to develop proposals and find solutions to provide developers and designers in the process of making decisions related to energy efficiency in rehabilitation interventions.

In the case of the addressed study it has been analyzed two constructive measures of passive type, (acting on the envelope) thirteen active actions (different energy systems) and the necessary combination between them to achieve multiple energy ratings. 26 hypothesis of energy rehabilitation have been analyzed, with their resulting energy ratings, assessing costs, its profitability and its impact on energy consumption and CO2 emissions.

The success of the energy refurbishment of a building depends on the selection of the adopted solutions, the investment cost for the works and the energy savings achieved. It is also necessary to take into account other non-quantifiable aspects such as greater comfort, better soundproofing, livability, health and the possibility of eliminating situations of energy poverty or the increase of property values.

The established procedure to address the case of study has followed the following steps:

  •  Analysis of the building corresponding to the case of study, considering its constructive and energetic characteristics, the average of consumption of natural gas, electricity and water and also climate data according to bioclimatic letters of Olgyay and Givoni.
  • The description, cataloging and evaluation of the actions to improve the envelope of the building, with the description of the strategies to reduce energy demand and its technical definition.
  • The description, cataloging and evaluation of the actions to improve the energy systems of the building.
  • The definition of 26 hypotheses by the combination of improving actions of the envelope and the energy systems.
  • The obtaining of results of each of the 26 rehabilitation hypotheses: energy rating, consumption and energy saving, construction costs and economic savings expected in energy consumption.
  •  Establishment of general conclusions on energy rehabilitation, economic results and observations about the tools used. 
Participantes: González Díaz, María Jesús; Valdivieso Rodríguez, Marta.