Search Results (26)

Preserving historical porous materials requires careful monitoring of surface humidity to mitigate deterioration processes like salt crystallization, mold growth, and material decay. While microclimate monitoring is a recognized preventive conservation tool, its role in detecting surface-specific moisture risks remains underexplored. This study evaluates the relationship between indoor microclimate fluctuations and surface moisture dynamics across 13 historical sites in Northern Italy (Lake Como, Valtellina, Valposchiavo), encompassing diverse masonry typologies and environmental conditions. High-resolution sensors recorded temperature and relative humidity for a minimum of 13 months, and eight indicators—including dew point depression, critical temperature–humidity zones, and damp effect indices—were analyzed to assess the moisture risks. The results demonstrate that multivariate microclimate data could effectively predict humidity accumulation. The key findings reveal the impact of seasonal ventilation, thermal inertia, and localized air stagnation on moisture distribution, with unheated alpine sites showing the highest condensation risk. The study highlights the need for integrated monitoring approaches, combining dew point analysis, mixing ratio stability, and buffering performance, to enable early risk detection and targeted conservation strategies. These insights bridge the gap between environmental monitoring and surface moisture diagnostics in porous heritage materials. Full article

Within museum depots, the largest part of all heritage collections is stored. Often, the preservation of highly sensitive objects is an ongoing challenge, as the materials are constantly subjected to and influenced by ever-present environmental factors—above all the surrounding climate and other physicochemical processes. Biological degradation is also a major risk for collections. Fungal infestation poses a particular threat, in many regions increasingly the result of climate change. Models for damage prediction and risk assessment are still underdeveloped and require a more substantial database. Approaching this need, nine museum depots and archives were selected in this study. Two years of monitoring the indoor microclimate with thermohygrometric sensors, investigating fungal abundance and diversity through culture-dependent and -independent (metagenomics) approaches, and the collection of relevant additional information resulted in a vast amount of diverse data. The main fungal genera identified through cultivation were Cladosporium, Penicillium, Aspergillus, Alternaria and Epicoccum. The cultivation-independent approach identified Aspergillus, Pyronema, Penicillium, Xenodidymella and Blumeria as the main taxa. Data analyses indicated that key drivers involved in similarities, patterns and differences between the locations were their geographic location, immediate outdoor surroundings and indoor (micro)climatic fluctuations. The study also sheds light on a possible shift in focus when developing strategies for preventing mold growth in collection depots beyond the prevailing path of tightest possible climate control. Full article

Assessments of indoor microclimates are the first act of preventive conservation of cultural heritage. Interest in this subject has led to the development of an increasing number of standards and guidelines. This critical review examines the application of the main standards and guidelines for indoor microclimates for the preventive conservation of cultural heritage and proposes their synthesis in a common framework. In this manner, this study tries to shed light on their coordination and to propose guidance for better understanding and application. Generally speaking, there are two kinds of guidelines: the first is based on the fixed values of specific parameters, used as limits for the best preservation of the various materials, whereas the second identifies the historical microclimate specific to the environment as the reference for appropriate preservation, especially in the case of organic and hygroscopic materials. After analysing different standards and guidelines, the various parameters and calculation methods are discussed and summarised in a table for a synoptic comparison. Full article

With the acceleration of urbanization, many traditional buildings have been dismantled and built indiscriminately, resulting in a uniform urban landscape. The problem of urban microclimate has been aggravated, and the renovation of historic districts, especially including the renewal of microclimate, has become an important component of sustainable urban renewal. The old commercial street in Huili Ancient City is used as an example in this paper. Through literature research, we note that previous studies have mainly examined the renewal of historic districts from the perspective of the old city environment, while most of the traditional neighborhood renewal designs have neglected the wind and heat environments. Combining the limitations of previous studies and field research, we summarized the current problems of the neighborhood and developed specific renovation strategies for the identified problems in terms of historical and cultural heritage, the relationship between the old and the new, and the layout of green building technologies. In addition, the green building strategy was used to optimize the microclimate environment of the neighborhood, and the wind and heat environment simulation was conducted to evaluate the modeling of the renovated neighborhood. The results show that the outdoor wind environment is better in winter than in summer, and the natural ventilation environment of the neighborhood could be optimized by optimizing the building layout to form an alleyway wind. The indoor wind–heat environment simulation was carried out with the Green Pottery Experience Hall as an example, and the indoor and outdoor air circulation and ventilation were good, and the comfort of the human thermal environment was high. This paper explores the updating strategy of the historic district in the transition zone between old and new and the wind–heat environment simulation and evaluation of green building renovation, which provides a new perspective for the related renovation research and the optimization strategy of the microclimate environment in the district. Full article

Energy rehabilitation of heritage buildings used as museums presents unique challenges, as it must balance the preservation of cultural heritage with achieving comfortable indoor conditions for visitors and staff. These objectives often conflict, requiring innovative approaches. We propose a methodology that uses dynamical simulation with EnergyPlus and multi-objective optimization with jEPlus + EA software to reduce energy consumption and maximize comfort while maintaining architectural integrity and conservation conditions evaluated by a quantitative analysis based on the European Standards. The framework also includes monitoring microclimate conditions and assessing the risk levels of the exposed collections. A case study in Salta City, Argentina—a historical building repurposed as a museum—illustrates this approach. Results show improved energy performance and comfort conditions for visitors, with an annual energy requirement of about 36% of the original requirement (16.4 kWh/m² versus 45 kWh/m²) and a decrease of about 32% in the discomfort hours (from 5362 h to 3643 h). Additionally, conservation conditions improved, achieving a more stable microclimate for air temperature and relative humidity. The framework proved useful for evaluating retrofit solutions that enhance the building’s energy performance and comfort without compromising the conservation conditions of the exhibited collections. Full article

Climate change poses significant challenges for the renovation of historic buildings, requiring a careful balance between preservation and energy efficiency, particularly considering the forecasted rise in temperatures. This study focuses on a medieval building undergoing renovation, examining thermal behaviors based on future climate settings, with particular attention to the rooms housing a book collection. Books require controlled microclimatic conditions that must be ensured for their preservation; hence, the energy use for air conditioning control must be considered during the renovation planning phase. Through on-site monitoring of the thermophysical properties of the building envelope and indoor microclimate, along with energy model software simulations, both historic climate and global warming scenarios were evaluated for their potential impact on thermal behavior and consequently on energy consumption. This study aims at contributing to the long-term sustainability and resilience of historic buildings, as well as proposing best practices for planning interventions involving sensitive cultural heritage materials, considering the effects of climate change in the renovation process. The results show strategies to address the climatic changes through a methodology optimizing renovation interventions. The sizing of air conditioning systems coupled with a less stringent microclimate control mitigates energy requirements, in line with the sustainable management approach. Full article

Fungi have always posed an unquestionable threat to heritage collections worldwide. Now, in a future of climate change, biological risk factors may have to be considered even more than before. Models and simulations to assess possible impacts a changing outdoor climate will have on indoor environments and, in turn, on biodeterioration are still underdeveloped and require a more substantial data basis. This study aimed at filling some of these knowledge gaps through a broad-based approach combining microclimatic and microbiological monitoring in four historic libraries in Austria with an uncontrolled indoor climate: Altenburg Abbey, Melk Abbey, Klosterneuburg Monastery and the Capuchin Monastery in Vienna. Data were generated from thermohygrometric sensors, cultivation-dependent air- and surface sampling and further surface dust sampling for cultivation-independent analyses. Results gave insights on the status quo of microbiological loads in the libraries and outdoor–indoor relationships. Influences of the geographic location and room-use on corresponding indoor fungal profiles were identified. Lower fungal diversities were found at the most rural site with the strongest climatic fluctuations and extreme values than in the most urban, sheltered library with a very stable climate. Further, the humidity-stabilizing potential of large collections of hygroscopic materials, such as books, was also examined. Implications for a sustainable approach to prevent future biodeterioration are discussed, supporting the long-term preservation of these valuable historic collections. Full article

The preservation of cultural artifacts within museums and historical buildings requires control of microclimatic conditions, and the constantly evolving climate certainly poses a challenge to maintaining recommended conditions. Focused on the Archaeological Museum of Delphi and the Church of Acheiropoietos in Greece, our study evaluates the hygrothermal behavior of these buildings with a specific emphasis on the preservation of cultural heritage objects hosted there. An innovative approach to the real-time analysis of data is utilized, aiming to achieve a timely detection of extreme temperature and humidity levels. A one-year monitoring campaign was carried out to achieve a detailed assessment of the indoor climate in selected museums and historical buildings in Greece. The monitoring campaign was performed using dataloggers that were set to measure and record temperature (T) and relative humidity (RH) values hourly. The results allowed for the detection of extreme temperature and relative humidity values, pinpointing the time period that requires more attention. The museum’s heating, ventilation, and air conditioning (HVAC) systems provide temperature control for visitor comfort, but the temperature still rises in summer, highlighting the impact of external climate factors. The church’s lack of HVAC systems widens the temperature range compared to the museum, but significant hourly fluctuations are not observed, underlining the building’s high thermal mass and inertia. Both buildings demonstrate a significant response to changes in outdoor temperature, emphasizing the need for future adaptation to climate change. The HMR_hs and PRD indices indicate minimal microclimate risk in both buildings for temperature and RH, reducing the probability of material damage. The church’s slightly higher HMR_hs index values, attributed to relative humidity, increases susceptibility due to sensitive materials. Overall, the study highlights the importance of managing microclimatic conditions in historical buildings and proposes careful adaptations for the protection of cultural heritage. Full article

The microclimate plays a crucial role in the conservation of historical cult buildings and their artifacts for future generations. In order to conserve these buildings and their artifacts, it is imperative to ensure that the microclimate is conserved. The norms and standards existing so far in Latvia do not stipulate thresholds for air parameters that would ensure a conserving microclimate for historical cult buildings. In order to identify these thresholds, the air parameters were measured simultaneously at nine measuring points within the Krimulda Church (LV) of the 13th century. The temperatures of the surfaces of the building envelope and potential condensation were calculated using the actual data of indoor and outside air. The indoor and outdoor air humidity ratio was calculated for each measurement. The conservation threshold of indoor microclimate parameters was determined by using intermittent heating on the basis of the air parameter fluctuations and calculations. The moisture vapours from the building structures were quantified in this research. The indoor humidity ratio during the warm season and the upper threshold during the heating season were determined. Full article

The preservation of historical buildings, as well as museum exhibition facilities, is critical under the changing environmental conditions. Since the potential outdoor climate changes may affect the recommended environmental conditions within the museum microenvironment, there is an urgent need for further research into the relationship between the outdoor and indoor climate and how future changes could affect it. This study investigated the relationship between the indoor and outdoor climate conditions in museums and historical buildings located in Greece. The main goal of this work was to assess the suitability of the indoor microclimate by applying the heritage microclimate risk (HMR) and the predicted risk of damage (PRD) indices. In order to achieve a detailed assessment of the present temperature and relative humidity (RH) outdoor conditions over the specific case studies, data from three different sources were incorporated in the study (observed, reanalysis, and model data). The model data were derived from the regional climate model RegCM4 with a fine spatial resolution of 10 × 10 km. The indoor environmental parameters were collected both from the museums and the historical buildings in the two case studies. In cases where indoor environmental data were not available, monitoring sensors were installed. The findings indicate that in cases where there is no control over climate conditions, the indoor climate is predominantly influenced by the outdoor climate. As a result, these spaces exhibit a heightened sensitivity to potential future temperature increases. Full article

This work presents the results of a microclimatic analysis in the church of San Panfilo in Tornimparte, in the Abruzzo region, Italy. The church of San Panfilo, dating from the XII–XIII century, preserves in the presbytery some marvelous frescoes of Saturnino Gatti (1494). A measurement campaign was organized from February 2021 to April 2022 with the aim of investigating the microclimate inside the church in view of the organization of fresco restoration. The monitoring activity was performed with intensive measurements on specific days during the year and with continuous measurements throughout the whole year. The main microclimatic parameters, relative humidity and temperature, were monitored in various sites inside and outside the church. Some physical quantities, such as dew point temperature, dew point spread and specific humidity, were computed from measured data. Measured and computed data permitted to evaluate the daily and monthly values, their evolution during the year, the daily fluctuations and delay times caused by the building. The resulting discussion allowed to identify potentially dangerous events for the conservation of the frescoes. Moreover, the historic climate inside the church was detected. Full article

A suitable indoor climate positively affects the lifespan of historical building structures. The path to an agreeable climate begins with monitoring current conditions. Considerable attention is given to monitoring the indoor climate of historical buildings. The motivation for monitoring air temperature and surface temperatures, relative air humidity or airflow can be, for example, the installation of heating, the occurrence of biotic damage, and others. Through the analysis of the most frequently used keywords, a strong connection was found, for example, between thermal comfort and the church. This review also summarises the various reasons for conducting microclimate monitoring studies in historical religious buildings on the European continent. It is supplemented with an evaluation of the monitoring methodology from the chosen period of the year point of view, the measured parameters, and the length of the interval between the recordings of quantities. It was found that in more than one-third of the cases, the recording time was less than or equal to 15 min, but mostly less than or equal to 1 h. Quite often, monitoring results are used to calibrate a simulation model describing the hydrothermal behaviour of a historical object under various operation alternatives (e.g., influence of ventilation, climate change, occupancy, etc.). This way, it is possible to test various intelligent systems in the virtual world without much risk before they are used in an actual building application. Full article

The current energy crisis and the necessity to minimize energy waste suggest the need to assess non-air-conditioned buildings in terms of the need to install an air-conditioning system and to size and control it efficiently. This applies to historical museum buildings hosting artworks that require specific microclimate conditions for their preservation. With this view, this work analyzes the suitability of non-air-conditioned historical museum buildings to properly preserve exhibits. Therefore, two non-air-conditioned museums located in the historical city center of Florence, Italy, are considered as case studies, i.e., Vasari Corridor and La Specola. One year of indoor microclimate data monitored in representative rooms of the museums are analyzed according to the standard for artworks preservation and in terms of historical climate. Results of monitored indoor air temperature and relative humidity show that all monitored rooms are not suitable for the preservation of the exhibits without the installation of an air-conditioning system. However, to minimize the energy consumption, the hygrothermal control can be based on the observed historical climate that characterizes the environments, which presents acceptable preservation ranges much wider that the reference technical standard. In this way, the energy needs for the environmental control necessary to ensure the good conservation of the artworks can be significantly reduced. Full article

An improper indoor microclimate has adverse effects on the state of preservation of historical textiles arranged in them, favoring the development of bacteriological microflora. The current study aims to combine traditional and innovative methods for cleaning and preserving a 100-year-old traditional blouse from Bihor, Romania. The material of the blouse was impregnated with 30 and 70 ppm silver nanosuspensions and washed with a substance obtained from boiling natural wood ash (lye). The research goals were to determine the antimicrobial action of lye washing and silver nanoparticles applied to the analyzed textile material and identify the way in which the environmental factors (light) act upon the conservation degree of textile objects impregnated with silver nanoparticles. All these procedures are eco-friendly and do not cause any damage to the constituent material of the fabrics. The use of the hyperspectral imaging technique proved the permeation of both 30 and 70 ppm silver nanosuspensions into the textile, producing changes in the textile’s reflectance spectrum after being treated with them. The results showed anti-bactericidal/fungal properties of both silver nanoparticles and lye. Microbiological analyses revealed that bacterial colonies were reduced to more than 95% in both cases. The antibacterial effect of silver nanoparticles on the textile material of the blouse was maintained throughout the duration of the study, and under normal environmental conditions, the effects would remain active for a long period. Full article

When dealing with the indoor microclimates of cultural and historical heritage cult buildings, it is important to know the types of these buildings by their spatial volumes and by the types of enclosing structures, and it is also important to understand the moisture transfer processes in these buildings, which would allow one to generate solutions on how to more effectively control the indoor microclimate. Due to the antiquity and specific load of these buildings, the existing standards are not applicable. This study summarizes 275 churches in Latvia, dividing them both according to five spatial volumes and according to the types of the materials used, which makes it possible to create potential air flows for all spatial volumes and to predict condensation risks in the future. Additionally, the results of temperature and humidity measurements in two different churches from one region of Latvia are given and the absolute humidity was calculated, and the data were analyzed depending on the outside air temperature. These measurements have yet to be followed up with the data of a full year. Full article