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The article presents selected issues related to raising energy standards of historical buildings. Due to their unique character, i.e. historic facades and architectural and decorative elements, the use of typical wall insulation methods, e.g. the ETICS system (External Thermal Insulation Composite Systems), is not possible. One solution is to insulate the external envelopes from the inside. Such an internal application method of insulation in the wall system has a significant impact on the profile of the occurring hygrothermal processes and it can trigger many unfavorable phenomena across the surface of the envelope. The design process and the selection of the type and thickness of insulation are carried out in accordance with commonly used criteria and principles – analogous to those used for newly designed buildings such as meeting minimum thermal insulation defined by the coefficient U and eliminating the risk of surface or interstitial condensation.

The article presents selected issues related to raising energy standards of historical buildings. Due to their unique character, i.e. historic facades and architectural and decorative elements, the use of typical wall insulation methods, e.g. the ETICS system (External Thermal Insulation Composite Systems), is not possible. One solution is to insulate the external envelopes from the inside. Such an internal application method of insulation in the wall system has a significant impact on the profile of the occurring hygrothermal processes and it can trigger many unfavorable phenomena across the surface of the envelope. The design process and the selection of the type and thickness of insulation are carried out in accordance with commonly used criteria and principles – analogous to those used for newly designed buildings such as meeting minimum thermal insulation defined by the coefficient U and eliminating the risk of surface or interstitial condensation. In thermal insulation systems from the inside, due to the specificity of the solution (lack of the continuity of thermal insulation), special attention should be paid to the places of connections and nodes in the insulated wall systems. Due to the lack of clearly defined criteria for designing such areas and insufficiently identified nature of hygrothermal processes occurring there, the following objectives were set in the work: identification and assessment of thermal insulation solutions within the selected 2D and 3D connections in thermal insulation systems from the inside in terms of avoiding adverse hygrothermal phenomena, indication of problems and threats that go along with such types of thermal modernization works. [ABSTRACT FROM AUTHOR]

Insufficient ventilation is one of the main factors leading to damp and mould in residential buildings. One low-cost method to improve these moisture-related issues is positive input ventilation (PIV) but research data on performance is scarce in the literature. This paper presents a bibliographical review together with a case study based on monitoring a residential building by means of environmental sensors. The review reveals the importance of correct location, installation, operation and continued maintenance of mechanical ventilation systems. Specifically, PIV and exhaust ventilation units in existing buildings require routine checking to ensure these systems are working correctly and efficiently. The results of monitoring ambient and surface temperature and relative humidity show that the PIV and enhancement extract fan set-up can reduce atmospheric moisture levels and avoid surface condensation. Mould growth is no longer active, but it is always essential to perform thoughtful building inspections checking the right conditions for installation and maintenance to ensure the proper functioning of the units. It is critical to study the size of the building and structural characteristics of the roof and ceilings. Also to verify that the doors are well undercut to allow air flow and that the occupancy levels and regional climate are adequate for selecting the appropriate type of mechanical ventilation units and corresponding operational modes (flow rates, operational settings, etc.). More research, measurements and monitoring studies pre- and post-installation of PIV and other whole house mechanical ventilation systems are recommended to assess optimal performances. This could also help to ensure the success of retrofitting projects in residential buildings which aim to improve energy efficiency but also make buildings relatively airtight and prone to condensation damp. An effective, sufficient and appropriate ventilation system as well as a good installation practice and adequate maintenance is key to avoid surface condensation and mould growth and to improve the indoor air quality of both new and existing buildings. [ABSTRACT FROM AUTHOR]

Metal - aluminium windows have an important position in residential architecture. High thermal conductivity, as the main material disadvantage of aluminium, is solved by decoupling the thermal bridge. With the improved geometry of the frames and the appropriate break of the thermal bridge, high-performance systems are achieved, used for all-glazed facades of various building categories around the world. Mathematical modelling methods enable highly accurate prediction of the system's behaviour, thereby achieving shape and material optimization of the frame and glazing concept. Despite this, there are products on the market that show defects of a thermal technical nature, which is caused, among other things, by the absence of a standard requirement for the minimum surface temperature of the window in some countries (e.g. the Czech Republic). The subject of the study is condensation on the surface of the glazing bead of aluminium lift-and-slide windows in a residential complex in eastern Slovakia. The occurrence of condensation is conditioned by operating boundary conditions – air temperature, relative air humidity, heating and ventilation mode. Through experimental measurements and subsequent modelling, the cause of the structural failure was determined, alternative solutions were proposed, and the optimal solution for adjusting the glazing bead was selected. The modelling methodology used is derived for use in determining condensation risk. With external boundary conditions from Typical Meteorological Year - ASHRAE 2.0 (TMY) for the Prešov (SK) location, the annual decrease in the amount of condensation and condensation time after the adjustment of the glazing bead compared to the original construction was determined.

The individualization of chromosomes during early mitosis and their clustering upon exit from cell division are two key transitions that ensure efficient segregation of eukaryotic chromosomes. Both processes are regulated by the surfactant-like protein Ki-67, but how Ki-67 achieves these diametric functions has remained unknown. Here, we report that Ki-67 radically switches from a chromosome repellent to a chromosome attractant during anaphase in human cells. We show that Ki-67 dephosphorylation during mitotic exit and the simultaneous exposure of a conserved basic patch induce the RNA-dependent formation of a liquid-like condensed phase on the chromosome surface. Experiments and coarse-grained simulations support a model in which the coalescence of chromosome surfaces, driven by co-condensation of Ki-67 and RNA, promotes clustering of chromosomes. Our study reveals how the switch of Ki-67 from a surfactant to a liquid-like condensed phase can generate mechanical forces during genome segregation that are required for re-establishing nuclear-cytoplasmic compartmentalization after mitosis. [Display omitted] • At anaphase onset, Ki-67 changes its properties upon dephosphorylation • Ki-67 forms condensates with premature ribosomal RNAs during anaphase • A charged patch in Ki-67's N terminus is required for condensate formation • Ki-67/pre-rRNA condensation is required for chromosome clustering Hernandez-Armendariz et al. show that Ki-67 generates a liquid-like layer with premature ribosomal RNAs on the chromosome surface to promote chromosome clustering during exit from mitosis. The transition of Ki-67 from chromosome repellent to attractant is triggered by a change in its phosphorylation status. [ABSTRACT FROM AUTHOR]

During the operation of twin screw expanders with slightly superheated vapours or even two-phase fluids, surface condensation on machine parts occurs during the filling period and the expansion phase when the working fluid is in contact with cooler inner surfaces. This heat exchange from the working fluid to adjacent machine parts effects the working cycle and the efficiency of these machines. Short time scales and the periodicity of the process indicate the condensation process is best described by models for dropwise condensation. In this paper the effects of surface condensation on the operation of twin screw expanders are initially discussed in a simulation-based investigation. Chamber model simulation coupled with a thermal analysis is used for the thermodynamic simulation, whereby heat transfer coefficients are systematically varied. It is found that during the inlet phase condensate emerges on the inner surfaces of the machine being substantially cooler than the working fluid. This results in a higher mass being trapped within the working chamber and, thus, an increasing mass flow rate of the machine. An increase in power output is, however, not observed. The results obtained from chamber model simulations are finally compared against experimental data of a screw expander prototype

The discoloration of building facades due to airborne algae is observed in our surroundings. The growth conditions of these algae are not yet fully understood, and efficient measures for preventing the growth of the algae are not presently available. The objective of this study was to investigate the effects of the ambient environment and building structure on algal growth. A residential building in a cold region of Japan was surveyed. The roof was a multi-layered structure comprising a semi-transparent film, an air layer, and a layer of insulation from the outside, supported by rafters. The soiled state was visually observed by taking photographs. On the northeast (NE) and northwest (NW) roofs, several black stripes appeared 4 months after cleaning. The soiling increased in the spring and autumn. The soiling first appeared on the film backed by the rafter and then extended to the film backed by the air layer. The condensation time during the day in the rafter part was longer than that in the air-layer part. Condensation occurred during the night, but its frequency exhibited no dependence on the orientation of the roof. Algae tend to die when exposed to an environment with a temperature higher than 45°C. The NE roof had the shortest period with a surface temperature of >45°C. These measurements agreed well with the survey results, which indicated that the soiling mainly occurred on the NE and NW sides of the roofs. The time for algal growth was estimated under the assumption that algae can grow at surface temperatures ranging from 0 to 45°C, in agreement with the observed soiling. The observed soiling changes were well explained by the algal population calculated via a growth predictive model according to the algal temperature and relative humidity. [ABSTRACT FROM AUTHOR]

Abstract In Korea, radiant floor heating systems are commonly used in residential buildings, even high-rise houses. If these existing radiant floor heating panels could be used for cooling as well, additional benefits beyond the basic advantages of radiant heating and cooling systems in terms of energy efficiency and comfort level could be conferred upon the homeowner, such as avoiding redundant investments for both heating and cooling equipment, and reducing the area occupied by the equipment. However, the comfort requirement of floor surface temperature has to be satisfied, because the human body comes in direct contact with the floor surface. In addition, dehumidification equipment is required to remove the latent load and to prevent surface condensation. It may be particularly difficult to apply such a system in high-rise residential buildings with massive concrete slabs as compared to light-weight buildings, because of the complexity of the system configuration and the thermal capacity of the building structure. In this study, the feasibility of radiant floor cooling systems (RFCS) for residential buildings with massive concrete slabs was evaluated. The strategy for the configuration and arrangement of an RFCS was based on the current configuration of the heating and cooling system as well as the cooling load. Then, through field testing, the performance of this system for cooling and condensation prevention was evaluated along with the occupants’ characteristics for adjusting parameters related to thermal comfort. As a result, an RFCS combined with supplementary equipment for dehumidification and cooling would satisfy the requirements for cooling and condensation prevention in a residential house with multi-zones.

• Enhanced resistance of ETICS finishing coats to microbiological colonization. • Improvement strategies based on thermal, hydrophobic and hydrophilic approaches. • Systematic study based on small- and large-scale laboratory tests. • Silicate-based formulations exhibit superior resistance to fungi and algae. • Glass microspheres and siloxane layers are insufficient to avoid bio-susceptibility. External thermal insulation composite systems (ETICS) are, in general, more likely to suffer from colonisation by fungi and algae than conventional walls, regardless of the nature of the biocide technology used. This results from the greater propensity of finishing coats applied on ETICS to develop surface condensation and, consequently, favourable conditions for microbiological growth. Most commonly, aesthetic degradation is the only implication. However, some severe cases can cause coating deterioration and loss of adhesion. In this work aiming to study resistance of ETICS finishing coats to fungi and algae growth, different improvement strategies based on thermal, hydrophobic, and hydrophilic approaches were exploited. In total, five different acrylic- and silicate-based formulations (without biocide) were prepared to screen the risk of condensation and biological resistance in separate small-scale laboratory tests. Based on the results obtained, selected finishing coats were applied on a large-scale ETICS wall and tested in a bioclimatic chamber capable of simulating conditions conducive to the early development of biological colonisation. The concomitant influence of biocides was also addressed at this stage. The results showed that a simple silicate-based formulation performs better than other tentative formulations tested, exhibiting a higher resistance to fungi and algae. They also suggested that incorporating glass microspheres or adding an external siloxane layer is not on its own effective in enhancing the resistance to the biological growth of acrylic- and silicate-based formulations. [ABSTRACT FROM AUTHOR]

This study reports the thermal characteristics of windows installed in the roof cladding of a block of flats in the second temperature zone of the Czech Republic, with boundary conditions for the design value θse = - 15 °C, according to the national standard ČSN 73 0540-3 (2005). The thermal behaviour of these elements was evaluated with regard to the condensation on roof windows, with four different types of spacer frames and the given boundary conditions, for maintenance of the thermal and technical humidity comfort of the interior. The tests of the surface temperatures of the diagnosed glazed roof units at the glazing of the wooden windows demonstrated that the SGG composite spacer was the best from a thermal perspective. The spacer frames based on aluminum, stainless steel, and a combination of stainless steel and plastic (TGI) did not provide adequate thermal insulation characteristics for usage in roof windows under the given climatic conditions, and condensation occurred on the glass surfaces.

The article presents four equivalent methods for checking mold growth on the surface of building barriers and checking water vapor condensation on their surface. Each method applies to two parallel phenomena that may occur on a building barrier. The first method is to calculate and compare temperature factors. In the second method, the characteristic humidity in the room is calculated and compared. The third method is to calculate and compare the characteristic temperatures in the room. The fourth method is based on the calculation and comparison of characteristic water vapor pressures. Three boundary conditions are presented for each method and phenomenon: when a given phenomenon can occur, when it begins or ends, and when it does not occur. The presented methods systematize the approach to the problem of mold development and surface condensation. The presented calculation results relate to the selected building barrier functioning in specific indoor and outdoor climate conditions. The calculation results confirm the compliance of the presented methods in identifying the phenomenon of mold growth or condensation on the surface of the barrier. A graphical interpretation of the results for each method with periods of occurrence or absence of a given phenomenon is also presented.

Condensation under the floor slabs of office rooms adjoining data centres is a serious concern because thermal comfort and information and communications technology equipment are both sensitive to high humidity levels. Surface condensation risk depends mainly on the surface energy balance and moisture content of ambient air. This paper describes an evaluation method for assessing condensation risk of indoor environment conditions and the effect of remedial measures and presents a strategy to solve the condensation risk problems using experimental measurements and numerical simulations. The condensation risks due to air temperature and humidity were calculated for two zones between information and communications technology server rooms and office areas. We analysed the structural insulation performance and space cooling conditions, supply air temperature of the information and communications technology server rooms. The change in indoor temperature of non-information and communications technology spaces was predicted to find the cause of the condensation state. The results show that application of floor slab insulation and high supply air temperature by the computer room air-conditioning unit can substantially increase the lowest temperature of the interior surfaces and the temperature factor and reduce indoor relative humidity, thus preventing surface condensation in the non-information and communications technology spaces adjacent to the information and communications technology server rooms. [ABSTRACT FROM AUTHOR]

This study reports the thermal characteristics of windows installed in the roof cladding of a block of flats in the second temperature zone of the Czech Republic, with boundary conditions for the design value θse = - 15 °C, according to the national standard ČSN 73 0540-3 (2005). The thermal behaviour of these elements was evaluated with regard to the condensation on roof windows, with four different types of spacer frames and the given boundary conditions, for maintenance of the thermal and technical humidity comfort of the interior. The tests of the surface temperatures of the diagnosed glazed roof units at the glazing of the wooden windows demonstrated that the SGG composite spacer was the best from a thermal perspective. The spacer frames based on aluminum, stainless steel, and a combination of stainless steel and plastic (TGI) did not provide adequate thermal insulation characteristics for usage in roof windows under the given climatic conditions, and condensation occurred on the glass surfaces. [ABSTRACT FROM AUTHOR]

Abstract: The methodology of protecting the European stained glass windows against environmental risk (e.g. meteorological factors, air pollution, microorganisms) by means of an external glazing is not new. In spite of many scientific studies carried out in the last 20years, some questions were still up for discussion. The European VIDRIO (2002–2005) project gave an answer to these questions. The research carried out by the different project partners established a new multidisciplinary approach aimed at evaluating the efficiency of the protective glazing systems and their effects on stained glass windows conservation, and finally at assessing the most appropriate strategy to preserve stained glass windows. Scientific results showed that the so-called isothermal glazing (i.e. ventilation by the air coming from the inside of the building) protected efficiently the ancient stained glass window from environmental attack (i.e. rain, pollutants, condensation, thermal shocks) with very limited secondary effects. The scientific research highlighted that its efficiency was strongly related to the technical design of the protective system. In particular, the ventilation and the size of the interspace had to be carefully considered. The research developed within the VIDRIO project was turned into general recommendations to the owners and practitioners on the best practice for the stained glass windows future conservation. [Copyright &y& Elsevier]

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Abstract: The microclimatic analysis of the Petrarca''s tomb in Arquà Petrarca, Padua (Italy) was performed to assess the suitability of a closed environment located outdoors respect to the conservation requirements of heritage materials. Results showed that the thermo-hygrometric conditions inside the tomb were not suitable for the conservation of organic materials, like bones and wood. The orientation (north or south) was the main responsible for the different damage features of the two sides of the wooden case housing the human remains inside the tomb. Technical solutions were finally implemented to improve the conservation conditions, thus avoiding further damage. [Copyright &y& Elsevier]

An estimation technique of the local heat transfer coefficient, based on the solution of the 2-D inverse heat conduction problem, has been adopted in order to investigate the effect of the surface wettability on the two-phase convective heat transfer in a dehumidifying process. The convective heat transfer coefficient distribution has been restored on aluminum plates coated with a hydrophobic oleic film on which the dropwise condensation of the water vapor carried by a humid air turbulent stream occurs. The refinement of the technique in relation to its ability of capturing the heat transfer local capability of the surface enables the appraisal of the heat transfer augmentation due to the hydrophobic surface coating. [ABSTRACT FROM AUTHOR]

Abstract: A numerical investigation was conducted to study mixed convection in a vertical parallel-plate channel with evaporation of thin liquid films on wetted walls. Air–water vapor and air–hexane vapor mixtures, assumed as ideal gases, are considered under various boundary conditions. Steady laminar, two-dimensional flows are examined in detail for large mixture density changes between the inlet and outlet sections of the channel. Comparisons with the usual problem formulations based on the Boussinesq approximation are discussed. The elliptic flow model used allow to predict flow reversal as well as recirculation cells in the entrance region. The evaporation of water and hexane into a downward laminar stream of dry air leads to various flow structures according to the interfacial mass fraction, , and differences in the molecular weights of the species. For water evaporation, the thermal and solutal forces are opposing. In the entrance region, evaporation produces a significant increase in axial velocity at the core region in comparison with pure forced flow. For larger than ≈0.2, upward velocities may be observed in the wall regions due to solutal buoyancy forces near the wetted surfaces. For hexane evaporation, the solutal force acts downward. Mass diffusion produces both a strong flow acceleration in the boundary layers and flow recirculations at the channel center for large mass evaporation rates. [Copyright &y& Elsevier]

Abstract: Heat transfer by natural convection and surface condensation in two-dimensional enclosures in contact with a cold external ambient through a wall of finite thickness was studied numerically. Special attention was given on the modeling of the flow of a binary mixture consisting of humid air. Low-Mach number assumption was introduced in order to account for decreases in mixture mass and average pressure within the enclosure between the initial and steady states. The computations show that thermodynamic balances are satisfied within the accuracy of the numerical procedure. The heat and fluid flows with and without condensation are compared for various operating conditions. It is shown that vapor condensation increases the heat transfer rate at the cold wall at the early stage of the transient regime. The decrease in the average density of the mixture leads to significant variable''s reductions at steady-state which, in turn, causes lower overall heat transfer rate than for dry air. [Copyright &y& Elsevier]

Abstract: The main sources of moisture on building façades are rain and condensation. Being moisture a prerequisite for the development of microbial growth it is of great interest to identify and analyse the factors responsible for these wetting mechanisms. The development of the microbial vegetation, in addition of being potentially damaging to the building envelope, creates a visual nuisance. This work aims to study the external environment conditions favourable for exterior surface condensation of buildings. The risk for occurrence of surface condensation depends mainly on the surface energy balance and on the moisture content of the ambient air. Because external surface temperature of buildings are very sensitive to convective and radiative exchanges, the investigation has been conducted analysing both convective and radiative heat transfer coefficients for a wide range of scenarios covering different climate sensitivities and building envelope qualities. The analysis has shown that convection and the moisture content of the air play a key role in the occurrence of surface condensations on building façades. [Copyright &y& Elsevier]

Abstract: Aluminum spacer used to keep the glass panes apart acts as a thermal bridge that increases the risk of inside surface condensation due to its high thermal conductivity. In this study, the inside surface condensation in double glazing window systems with conventional aluminum spacer and insulation spacers made of thermally broken aluminum and thick-walled plastic, respectively, is evaluated. Evaluation method and judgment criteria for preventing inside surface condensation are suggested. Thermal characteristics of window system in residential unit are analyzed and two-dimensional steady state heat transfer simulation is carried out in order to obtain the lowest inside surface temperature. The results show that the application of insulation spacer can substantially increase the lowest inside surface temperature, temperature difference ratio and inside air humidity for preventing inside surface condensation and satisfy the required minimum temperature difference ratio. [Copyright &y& Elsevier]

This paper presents a method to solve condensation problems by using computational fluid dynamic method (CFD). At first, a 3-D transient CFD model for simulating condensation is developed. Then controlled experiment was conducted in a test chamber to validate this model. The results indicate that there is a good agreement between the experimental results and the model predictions. The simulation reveals the process of condensation in the chamber, which was observed in the experiment as well, significant water droplet condensation and frost buildup were observed at the regions corresponding to the simulation. In addition, the simulation confirms with the long been recognized effect of ventilation on condensation risk. It is found that properly located vent could help reduce condensation risks. [Copyright &y& Elsevier]

We propose a surface condensation method for assembling single-walled carbon nanotubes (SWNTs) on gold. The as-prepared long and randomly tangled SWNTs were cut into short pipes by chemical oxidation, allowing the nanotubes to be terminated by carboxyl functionalities. A surface condensation reaction was then performed by immersing an amino self-assembled monolayer (SAM)-modified gold substrate into the dimethylformamide suspension of carboxylic nanotubes with the aid of dicyclohexylcarbodiimide condensation agent. Raman spectroscopy and atomic force microscopy (AFM) results show that a highly aligned assembly of SWNTs has been formed on gold, with the nanotubes standing on the surface stable enough for a long ultrasonication. In combination with the microcontact printing (μCP) technique, we have fabricated patterned nanotube assemblies using this surface condensation method. Moreover, we found that the “giant” carbon nanotubes tend to form bundles on an amino-terminating surface, likely following a nucleation-growth model. [Copyright &y& Elsevier]

The possibility of surface catalysed condensation of unsubstituted amino acids on kaolinite in aqueous systems at elevated temperatures was investigated; no evidence of clay catalysed polycondensation has been found. The thermodynamic feasibility of the hypothetical lysine/dilysine condensation reaction in the temperature-range up to 90° C was evaluated for a range of experimental conditions by the combination of measured free energies of lysine/dilysine cation exchange on kaolinite and on montmorillonite, and free energies for the analogous condensation reaction in homogeneous solution. The results indicate that, in spite of the high selectivity of the clays for the adsorption of cation dimers from dilute solutions, the thermodynamic barrier to the surface condensation of unsubstituted amino acids on clay minerals in aqueous systems up to 90° C is not lower than it is in homogeneous solution. [ABSTRACT FROM AUTHOR]

The main purpose of thermal insulation in buildings is to reduce conductive heat loss and maintain appropriate interior surface temperatures. How ever, ensuring the desired performance requires not only good workmanship during construction but also careful prediction of the hygro-thermal behavior of building components with complex geometry and material composition (thermal bridges). This paper includes the results of a study of insulated building components typical to the construction practice in North America, concentrating on low-rise residential and commercial buildings. It deals specifically with the significance of the accurate simulation of conductive heat transfer for both energy (heat load calculations) and building integrity issues (surface condensation). [ABSTRACT FROM PUBLISHER]

All across North America, the hotel industry has been plagued by moisture problems leading to odor, staining, and structural degradation. According to a 1990 survey by the Association of Hotels and Motels (AHM), mold and mildew costs the industry about 68 million dollars per year in lost revenues and repairs. The association suspects that these problems stem from faulty design of building enve lope and HVAC systems. Indeed, this case study of two buildings supports AHM assumptions and illustrates how the design faults may lead to excessive wetness and mold growth in hotels and motels in Florida. [ABSTRACT FROM PUBLISHER]

A theoretical method is descnbed to evaluate the rate of vapour generation inside a residential building in which surface condensation may occur on the interior sur face of external walls.The analytical model refers to an ambient surrounded by multilayered internal and external walls; the latter subjected to variable outside boundary conditions.Results show that the amount of vapour generation permissible inside without condensation depends on the orientation of the ambient and on the thermal storage capacity of its external and internal walls. [ABSTRACT FROM PUBLISHER]

The article presents four equivalent methods for checking mold growth on the surface of building barriers and checking water vapor condensation on their surface. Each method applies to two parallel phenomena that may occur on a building barrier. The first method is to calculate and compare temperature factors. In the second method, the characteristic humidity in the room is calculated and compared. The third method is to calculate and compare the characteristic temperatures in the room. The fourth method is based on the calculation and comparison of characteristic water vapor pressures. Three boundary conditions are presented for each method and phenomenon: when a given phenomenon can occur, when it begins or ends, and when it does not occur. The presented methods systematize the approach to the problem of mold development and surface condensation. The presented calculation results relate to the selected building barrier functioning in specific indoor and outdoor climate conditions. The calculation results confirm the compliance of the presented methods in identifying the phenomenon of mold growth or condensation on the surface of the barrier. A graphical interpretation of the results for each method with periods of occurrence or absence of a given phenomenon is also presented. [ABSTRACT FROM AUTHOR]

Among the possible pathologies in buildings, one of the main occurrences in humid climates is the appearance of mold. The mold growth on envelope inside surfaces is not exclusively due to failure on building execution and waterproofing. Factors such as, the air relative humidity, inside air temperature, and surface condensation, are aspects that could cause the mold emergence. In this context, the present research was carried out in order to understand the influence of the use of thermal insulation and the solar orientation of the walls in the mold growth in naturally ventilated residences. This study is developed in the humid temperate climate (Köppen Cfa) of Florianópolis, Brazil, located in South America. For this, simulations in the EnergyPlus software, version 8.8, were performed. The residence was simulated by varying the use of thermal insulation in external walls: thermal insulation on the internal side of the wall, insulation on the outer side of the wall and wall without insulation. Two solar orientations were adopted, being north and south. Based on the results found, it was observed how the constructive parameters affect the periods of occurrence of ideal conditions for formation and growth of the mold. It was found that when the rooms were facing north, fewer occurrences of long periods satisfying the conditions for the appearance of the mold occurred. It was also observed that the non-use of thermal insulation reduced these occurrences when the performance among construction systems was compared. This effect also occurred due to the increase in air changes in this model. • The use of thermal insulation affects the favorable conditions of mold growth. • The seasons of the year showed as a crucial factor for mold development. • The occurrence of satisfaction conditions to mold happened often for long periods. • The intensity factor become the results more intelligible. [ABSTRACT FROM AUTHOR]

In Korea, radiant floor heating systems are commonly used in residential buildings, even high-rise houses. If these existing radiant floor heating panels could be used for cooling as well, additional benefits beyond the basic advantages of radiant heating and cooling systems in terms of energy efficiency and comfort level could be conferred upon the homeowner, such as avoiding redundant investments for both heating and cooling equipment, and reducing the area occupied by the equipment. However, the comfort requirement of floor surface temperature has to be satisfied, because the human body comes in direct contact with the floor surface. In addition, dehumidification equipment is required to remove the latent load and to prevent surface condensation. It may be particularly difficult to apply such a system in high-rise residential buildings with massive concrete slabs as compared to light-weight buildings, because of the complexity of the system configuration and the thermal capacity of the building structure. In this study, the feasibility of radiant floor cooling systems (RFCS) for residential buildings with massive concrete slabs was evaluated. The strategy for the configuration and arrangement of an RFCS was based on the current configuration of the heating and cooling system as well as the cooling load. Then, through field testing, the performance of this system for cooling and condensation prevention was evaluated along with the occupants' characteristics for adjusting parameters related to thermal comfort. As a result, an RFCS combined with supplementary equipment for dehumidification and cooling would satisfy the requirements for cooling and condensation prevention in a residential house with multi-zones. [ABSTRACT FROM AUTHOR]