Historic Buildings and Energy Efficiency

Abstract

This paper aims to critically examine the issue of rendering historic buildings energy efficient. Although this subject has been discussed to some extent on the national and international levels, it largely has been under-theorised as the existing literature focuses mainly on technical matters related to the improvement of energy performance. Indeed, one of the main issues which has not been thoroughly addressed in the literature is balancing conservation needs on the one hand and improved energy performance of historic buildings on the other, partly due to improper analytical tools, methods, and parameters that are commonly used to classify the energy behaviour of historic buildings. It is the matter of insufficient existing tools which triggered the development of this paper. This paper is based on experimental measurements in order to determine the most relevant parameters and the average thermo-physical data of the historic building envelope. The experiments were followed by evaluation of the energy performance of three listed buildings in Italy using static (used for energy certification in Italy), semi- dynamic, and dynamic computer simulations, in order to understand which energy audit schemes best simulate the actual energy performance of historic buildings while identifying the strengths and limitations of each type of software. The simulations were carried out using experimental data on the thermo-physical parameters of the building envelope components, energy bills, temperature, and relative humidity of air. The ultimate goal was to define the appropriate intervention for ‘particular’ types of historic buildings, in order to optimise the energy-efficiency requirements along with preservation of their inherent cultural values.