Dynamic simulation and on-site measurements for energy retrofit of complex historic buildings: Villa Mondragone case study Cristina Cornaro a,b,n , Valerio Adoo Puggioni c , Rodolfo Maria Strollo d a Department of Enterprise Engineering, University of Rome, Tor Vergata, Via del Politecnico,1, 00133 Rome, Italy b CHOSE, University of Rome Tor Vergata, Via del Politecnico,1, 00133 Rome, Italy c EnUp srl, Via dei Monti di Primavalle,151, Rome, Italy d LAREA LAboratorio di Rilievo E Architettura, University of Rome Tor Vergata, Via del Politecnico,1, 00133 Rome, Italy article info Article history: Received 26 November 2015 Received in revised form 3 February 2016 Accepted 3 February 2016 Available online 4 February 2016 Keywords: Historic buildings Microclimatic measurements Dynamic simulation IDA ICE Retrofit Energy efficiency abstract The paper presents a method involving on-site measurements and dynamic simulation to evaluate re- furbishment solutions of an extended and complex building of great artistic and historical value, Villa Mondragone, located in the Colli Albani area and property of the University of Rome Tor Vergata. The approach has been successfully applied to a historic building of great construction complexity that was built during centuries, superimposing different construction technologies and styles. Masonry char- acteristics of ancient buildings are often hard to find and in situ measurements of thermal parameters (U- values) are time consuming, especially for large estates with structures of various superimposed ages as the case of Villa Mondragone. The paper demonstrates how a specific calibration of the dynamic model using only indoor temperature measurements can overcome this problem. The model was used to evaluate the energy performance of the actual use of the Villa and two possible cases of intervention. An improvement of approximately 40% in the energy demand has been evaluated adopting refurbishment solutions without impact on the historical value of the building. The model could be used also in the future to evaluate various refurbishment solutions not only regarding the envelope but also the plant and its use. & 2016 Elsevier Ltd. All rights reserved. 1. Introduction Recently the European Council confirmed the objective of re- ducing greenhouse gas emissions by 80–95% by 2050 compared to 1990 [1]. The construction sector has a primary role in the CO 2 reduction in Europe since buildings use around 40% of total energy consumption and generate almost 36% of greenhouse gases in Europe. Allouhi et al. [2] presented recent data on the world en- ergy consumption in both residential and commercial buildings together with an overview of measures and policies adopted by different countries, for the reduction of energy consumption in buildings. The refurbishment of the existing building stock is the greatest challenge, also more significant than the construction of new and nearly zero energy buildings. The new Energy Efficiency Directive 2012/27/EU [3] gave great attention to public buildings, indeed, from January 2014, a share of 3% of buildings owned and/or occupied by public institutions should be refurbished yearly. Europe building heritage consists of a great part of historical buildings and recently European Community funded two Eur- opean projects on sustainability and energy efficiency of cultural heritage [4,5] stressing the importance of looking at historic buildings as a value from an economical, energy and environ- mental point of view. Furthermore also from the research point of view, growing numbers of papers in the literature deal with the retrofit of his- toric buildings as pointed out by the recent special issue published by Energy and Buildings [6]. In Italy, energy retrofit is not mandatory for historical buildings, this because historic heritage is considered a priority with respect to energy performance [7]. However, considering that many historic buildings are property of public institutions such as for example Universities and Mu- seums, public sector will have to cope with this issue preserving cultural integrity and improving energy efficiency. Taking into account these two important features entails less flexibility in the proposal of energy efficiency measures. Many works can be found in the literature regarding the eva- luation of energy efficiency in buildings undergone refurbishment and most of these works are focused on residential buildings and/ Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/jobe Journal of Building Engineering http://dx.doi.org/10.1016/j.jobe.2016.02.001 2352-7102/& 2016 Elsevier Ltd. All rights reserved. n Corresponding author at: Department of Enterprise Engineering, University of Rome Tor Vergata, Via del Politecnico,1, 00133 Rome, Italy E-mail address: cornaro@uniroma2.it (C. Cornaro). Journal of Building Engineering 6 (2016) 17–28