A method for an effective microclimate management in historical buildings combining monitoring and dynamic simulation: the case of “Museo Archeologico di Priverno”

In this work a method is proposed to estimate the effect of indoor microclimate on the risk of degradation of ancient materials stored in historical buildings. The method, which combines microclimate observations and dynamic simulation, has shown to be strategic in preventive conservation of historical buildings. Indeed, once the building model is calibrated, it can be effectively used for evaluating the microclimate control solutions on the conservation reducing general degradation risks. The method has been applied to a historical building close to Rome, where deteriorations in ceilings occurred and visitors complain about thermal discomfort. First, the HVAC system in the model has set in order to guarantee both thermal comfort and adequate condition for the conservation of the material. Then, the crack width of wooden ceiling has been estimated by means of an empirical model based on indoor temperature and relative humidity data and validated with the measurements of the crack width. It was found a reduction of annual variation from 0.4 mm to 0.2 mm, experimented by panels, and an improvement of maximum daily variation, especially in winter and summer (less than 0.01 mm on average)

Optimising conservation of artworks, energy performance and thermal comfort combining hygrothermal dynamic simulation and on-site measurements in historic buildings

The indoor climate conditions being suitable for the conservation of cultural heritage can be conflicting with energy saving and thermal comfort. Moreover, the moisture dynamics have not been studied enough in the simulation of the indoor environment, even though its interaction with artworks is crucial in deterioration phenomena. This research aims at defining a strategy, based on experimental data and dynamic simulation of hygrothermal behaviour, in order to design a HVAC system able to simultaneously satisfy conservation, thermal comfort and energy requirements. A weighted function for the multi-objective optimization has been proposed and effectively used to pinpoint the combination of temperature and relative humidity set-points

Performance assessment of hygrothermal modelling for diagnostics and conservation in an Italian historical church

The hygrothermal modelling of historical churches is a promising approach to study preservation issues and suitable retrofit measures. However, difficulties can arise in the use of Heat, Air and Moisture (HAM) models, which are often customised objects to be integrated into validated building energy simulation (BES). This research outlines a multi-step methodology to investigate the capability of a BES software coupled with a HAM model (BES + HAM) as a technique for diagnostics and conservation in complex settings. The 17th-century church of Santa Rosalia (Italy) was used as a historical site in a real context. As first step, the performance of the simulation tool was analysed through standardised exercises aiming at excluding incorrect assumptions and calculations in the HAM model (HMWall). Secondly, a building model of the church using a 1D heat transfer model (named building model A) was compared with one using HMWall (named building model B) in terms of the accuracy of the indoor climate simulations against hygrothermal measurements. The results showed that building model B enhanced the simulation accuracy by +50% with respect to building model A. Finally, annual simulations inside the church were run to further compare the seasonal trends of indoor climate scenario obtained from the two building models. Building model B allowed to study the water content distribution inside the altarpiece and a wall partition, showing that BES + HAM tools can be used to identify potential moisture-induced conservation risks

Investigation on the Use of Passive Microclimate Frames in View of the Climate Change Scenario

[EN] Passive microclimate frames are exhibition enclosures able to modify their internal climate in order to comply with paintings¿ conservation needs. Due to a growing concern about the effects of climate change, future policies in conservation must move towards affordable and sustainable preservation strategies. This study investigated the hygrothermal conditions monitored within a microclimate frame hosting a portrait on cardboard with the aim of discussing its use in view of the climate expected indoors in the period 2041¿2070. Its effectiveness in terms of the ASHRAE classification and of the Lifetime Multiplier for chemical deterioration of paper was assessed comparing temperature and relative humidity values simultaneously measured inside the microclimate frame and in its surrounding environment, first in the Pio V Museum and later in a residential building, both located in the area of Valencia (Spain). Moreover, heat and moisture transfer functions were used to derive projections over the future indoor hygrothermal conditions in response to the ENSEMBLES-A1B outdoor scenario. The adoption of microclimate frames proved to be an effective preventive conservation action in current and future conditions but it may not be sufficient to fully avoid the chemical degradation risk without an additional control over temperatureThis project received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 814624. This research was partially supported by the Plan Nacionalde I+D, Comision Interministerial de Ciencia y Tecnologia (FEDER-CICYT) under project HAR2013-47895-C2-1-P.Verticchio, E.; Frasca, F.; García Diego, FJ.; Siani, AM. (2019). Investigation on the Use of Passive Microclimate Frames in View of the Climate Change Scenario. Climate. 7(8):1-14. https://doi.org/10.3390/cli70800981147

Examination on total ozone column retrievals by Brewer spectrophotometry using different processing software

The availability of long-term records of the total ozone content (TOC) represents a valuable source of information for studies on the assessment of short-and long-term atmospheric changes and their impact on the terrestrial ecosystem. In particular, ground-based observations represent a valuable tool for validating satellite-derived products. To our knowledge, details about software packages for processing Brewer spectrophotometer measurements and for retrieving the TOC are seldom specified in studies using such datasets. The sources of the differences among retrieved TOCs from the Brewer instruments located at the Italian stations of Rome and Aosta, using three freely available codes (Brewer Processing Software, BPS; O3Brewer software; and European Brewer Network (EUBREWNET) level 1.5 products) are investigated here. Ground-based TOCs are also compared with Ozone Monitoring Instrument (OMI) TOC retrievals used as an independent dataset since no other instruments near the Brewer sites are available. The overall agreement of the BPS and O3Brewer TOC data with EUBREWNET data is within the estimated total uncertainty in the retrieval of total ozone from a Brewer spectrophotometer (1%). However, differences can be found depending on the software in use. Such differences become larger when the instrumental sensitivity exhibits a fast and dramatic drift which can affect the ozone retrievals significantly. Moreover, if daily mean values are directly generated by the software, differences can be observed due to the configuration set by the users to process single ozone measurement and the rejection rules applied to data to calculate the daily value. This work aims to provide useful information both for scientists engaged in ozone measurements with Brewer spectrophotometers and for stakeholders of the Brewer data products available on Web-based platforms

Novel Model Based on Artificial Neural Networks to Predict Short-Term Temperature Evolution in Museum Environment

The environmental microclimatic characteristics are often subject to fluctuations of considerable importance, which can cause irreparable damage to art works. We explored the applicability of Artificial Intelligence (AI) techniques to the Cultural Heritage area, with the aim of predicting short-term microclimatic values based on data collected at Rosenborg Castle (Copenhagen), housing the Royal Danish Collection. Specifically, this study applied the NAR (Nonlinear Autoregressive) and NARX (Nonlinear Autoregressive with Exogenous) models to the Rosenborg microclimate time series. Even if the two models were applied to small datasets, they have shown a good adaptive capacity predicting short-time future values. This work explores the use of AI in very short forecasting of microclimate variables in museums as a potential tool for decision-support systems to limit the climate-induced damages of artworks within the scope of their preventive conservation. The proposed model could be a useful support tool for the management of the museums

A Comprehensive study of the microclimate-induced conservation risks in hypogeal sites. The mithraeum of the Baths of Caracalla (Rome)

The peculiar microclimate inside cultural hypogeal sites needs to be carefully investigated. This study presents a methodology that aimed at providing a user-friendly assessment of the frequently occurring hazards in such sites. A Risk Index was specifically defined as the percentage of time for which the hygrothermal values lie in ranges that are considered to be hazardous for conservation. An environmental monitoring campaign that was conducted over the past ten years inside the Mithraeum of the Baths of Caracalla (Rome) allowed for us to study the deterioration before and after a maintenance intervention. The general microclimate assessment and the specific conservation risk assessment were both carried out. The former made it possible to investigate the influence of the outdoor weather conditions on the indoor climate and estimate condensation and evaporation responsible for salts crystallisation/dissolution and bio-colonisation. The latter took hygrothermal conditions that were close to wall surfaces to analyse the data distribution on diagrams with critical curves of deliquescence salts, mould germination, and growth. The intervention mitigated the risk of efflorescence thanks to reduced evaporation, while promoting the risk of bioproliferation due to increased condensation. The Risk Index provided a quantitative measure of the individual risks and their synergism towards a more comprehensive understanding of the microclimate-induced risks

Assessing the Impact of Climate Change on the Biodeterioration Risk in Historical Buildings of the Mediterranean Area: The State Archives of Palermo

The growing sensitivity towards environmental sustainability, particularly in the light of climate change, requires a reflection on the role that historical buildings can play in heritage conservation. This research proposed an interdisciplinary approach combining climate and biological expertise to evaluate the biodeterioration risk associated with different IPCC outdoor climate scenarios. Conduction heat transfer functions and dose–response functions were used to model the indoor climate of a historical building and the related climate-induced risk of mould and pest proliferation. The approach was applied to a case study in the Mediterranean area, i.e., the State Archives of Palermo (Italy) housed in a 15th-century convent. In 2018, a survey conducted by ICPAL-MiC experts warned about past infestations and risks deriving from climate conditions. An environmental monitoring campaign conducted in 2021 allowed for the characterisation of the buffering effect in a historical building in response to the outdoor climate and the simulation of future indoor climate. Since indoor temperature and mixing ratio are expected to raise in future scenarios, it was found that there is an increased risk of insects’ proliferation, combined with a decreased risk of spore germination and mould growth. Such evidence-based evaluation allows for the design of tailored preventive conservation measures to enhance the durability of both the archival collections and the building

A comparison among three whole-building dynamic simulation software and their applicability to the indoor climate modelling of historical buildings

Building energy simulations are important to assess the performance of buildings and to design solution aimed at reducing energy consumption and carbon emissions. Many software perform these simulations, focusing on systems operations and energy losses and gains. When it comes to modelling historical buildings, the simulations could be also used to estimate the risk of damages and decay processes. This paper presents the first results based on twelve standardised exercises at increasing complexity for the comparison of microclimate simulations modelled through three whole-building hygrothermal dynamic simulation (BDS) software, specifically IDA ICE, WUFI PLUS and ENERGY PLUS. Differently from the already available testing procedures, this research focused on the physical variables that are relevant for conservation of historical buildings (i.e., temperature (T) and relative humidity (RH)). Starting from Common Exercise 0 (CE0), seven simulations were customised to capture differences in T values. Then, five building models were specifically conceived to consider some typical features of Historical Buildings (HB0): small windows size, heavyweight structures, low insulation of roofs, large volume and free-floating conditions. In the case of CE0, a good agreement was found in the simulation of indoor T. In addition, detailed windows reduced the discrepancy in T results with respect to the use of simplified windows. In the case of HB0, small windows slightly affected the microclimate simulations regardless of the number of transparent elements and their position. RH variability was driven only by T as the partial water vapour pressure was affected only by infiltrations through the building. To conclude, the comparison allowed to highlight some criticalities due to different model implementations such as weather file timestamp interpretation, window models or irradiation calculations. HB0 models could be used for software and models comparisons, new software testing and training activities

A quantitative comparison on the use of thermal insulation materials in three European countries through the TEnSE approach: Challenges and opportunities

Europe has about 75 % of energy inefficient buildings and 8 % of population in energy poverty with difficulties of affording energy bills for keeping adequate levels of warmth, cooling, lighting, and energy use for household appliances in building stock. The implementation of thermal insulation in existing buildings would allow to address both energy efficiency and energy poverty and to align with the Net Zero Emission Scenario. This research proposes an inverse decision-making approach to investigate on the reasons behind the use of some thermal insulation materials in three countries within the European Economic Area (Italy, Norway, and Portugal), differing in terms of Energy Poverty as well as environmental and legislative contexts. For this reason, four macro-domains objectives, framed in Technical (T), Environmental (En), Safety (S) and Economic (E) topics, named as TEnSE, were considered. Ten thermal insulation materials commonly used in these countries were compared to understand which of four perspectives affects their choices in current times among several stakeholders. As none of the selected materials has obtained the highest score among stakeholders and their use is presumably due to buildability, challenges and opportunities in their future implementation are discussed considering different climate ‘what-if’ scenarios