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The purpose of this study is to analyze the question “In what order of magnitude does the comfort and performance improvement lie with the use of a cooling vest for construction workers?”.

The use of personal cooling systems, in the form of cooling vests, is not only intended to reduce the heat load, in order to prevent disruption of the thermoregulation system of the body, but also to improve work performance. A calculation study was carried out on the basis of four validated mathematical models, namely a cooling vest model, a thermophysiological human model, a dynamic thermal sensation model and a performance loss model for construction workers.

The use of a cooling vest has a significant beneficial effect on the thermal sensation and the loss of performance, depending on the thermal load on the body.

Each cooling vest can be characterized on the basis of the maximum cooling power (Pmax; in W/m²), the cooling capacity (Auc; in Wh/m2) and the time (tc; in minutes) after which the cooling power is negligible. In order to objectively compare cooling vests, a (preferably International and/or European) standard/guideline must be compiled to determine the cooling power and the cooling capacity of cooling vests.

It is recommended to implement the use of cooling vests in the construction process so that employees can use them if necessary or desired.

Climate change, resulting in global warming, is one of the biggest problems of present times. Rising outdoor temperatures will continue in the 21st century, with a greater frequency and duration of heat waves. Some regions of the world are more affected than others. Europe is one of the regions of the world where rising global temperatures will adversely affect public health, especially that of the labor force, resulting in a decline in labor productivity. It will be clear that in many situations air conditioning is not an option because it does not provide sufficient cooling or it is a very expensive investment; for example, in the situation of construction work. In such a situation, personal cooling systems, such as cooling vests, can be an efficient and financially attractive solution to the problem of discomfort and heat stress.

The value of the study lies in the link between four validated mathematical models, namely a cooling vest model, a thermophysiological human model, a dynamic thermal sensation model and a performance loss model for construction workers.

This article is a proposal and aims to be a first step to develop a method to evaluate and classify environmental noise, according to EN‐15251 and CR‐1752, in the built environment based on the percentage of dissatisfied related to the equivalent background noise level.

In the European guideline CR‐1752 and the standard EN‐15251 three categories of the indoor environment in buildings are prescribed (category A, B and C). In the recommendations, the limit whereby the percentage of dissatisfied should remain under varies in each category for both the thermal indoor environment and the air quality. The categories for noise and illumination criteria are not yet explicitly related to a percentage of dissatisfied.

Using the percentage of dissatisfied as the evaluation criterion, when related to the equivalent background noise, produces a more refined evaluation of comfort than an evaluation based on the percentage of seriously disturbed or the effects of sleep deprivation in relation to external noise. Furthermore, this corresponds to the European standards and recommendations concerning quality classification of the indoor environment, based on the percentage of dissatisfied.

Based on recent European undertakings concerning the development of categories for the indoor environment based on the percentage of dissatisfied, it is desirable to utilise these categories to noise aspects too, and to relate it to the equivalent background noise level.

The purpose of this paper is to adduce the most appropriate thermal comfort assessment method for determining human thermal comfort and energy efficient temperature control in office buildings in tropical West Africa.

This paper examines the Adaptive Thermal Comfort Standard, from its research evolution to its contemporary use as an environmental design assessment Standard. It compares the adaptive component of ASHRAE Standard 55 and the European CEN/EN 15251. It begins by reviewing relevant literature and then produces a comparative analysis of the two standards, before suggesting the most appropriate Adaptive Thermal Comfort Standard for use in assessing conditions in tropical climate conditions. The suggested Standard was then used to analyse data collected from the author's pilot research into thermal conditions, in five office buildings situated in the city of Enugu, South Eastern Nigeria.

The paper provides insight as to why the ASHRAE adaptive model is more suitable for thermal comfort assessment of office buildings in the tropical West African climate. This was demonstrated by using the ASHRAE Thermal Comfort Standard to assess comfort conditions from pilot research study data collected on Nigerian office buildings by the author.

The paper compares the adaptive component of ASHRAE Standard 55 with CEN/EN 15251, and their different benefits for use in tropical climates. It suggested the need for further research studies and application of the ASHRAE Adaptive Thermal Comfort Standard in the tropical West African climate.

There is a clear consensus that improving energy efficiency of existing housing stock is necessary to meet the UK’s legally binding carbon emission targets by 2050. The purpose of this paper is to assess the energy saving potentials from building retrofit using an end-terrace house, similar houses represent about 30 per cent of the existing building stock in the UK.

The Salford Energy House – a unique pre-1919 Victorian end-terrace house built within an environmental chamber – was used. Retrofit modelling analysis was carried out using IESVE – a dynamic thermal simulation tool. The retrofitted model was also evaluated using future projected climate data (CIBSE latest release) to examine energy demands and overheating.

Findings show that improving building fabric thermal characteristics can reduce space heating demands substantially. Heating modes, set point preferences and infiltration level all have strong impact on heating demands. Space heating demand savings can be as much as 77 per cent when the property facades were upgraded to the similar requirements of Passivhaus standards. The research implicates that, for dwelling retrofit practices, a whole house holistic approach should be the preferred option to improve energy efficiency. With future climate scenarios where temperatures are potentially elevated, the heating demands can be potentially reduced as much as 27 per cent.

The likelihood of overheating in dwellings after a deep retrofit due to future elevated temperatures becomes apparent. Therefore, mitigation of overheating risk becomes a necessity for future domestic housing stock retrofit planning and policy making.

The research presented in this paper highlights the effectiveness of various retrofit measures individually as well as holistically, also the implications on energy demands and the likelihood of overheating in dwellings under future climate scenarios.

Numerous studies have shown that indoor environment affects health and performance, which in turn affect productivity. Property owners have not utilized Indoor Environment Quality (IEQ) as a value‐added factor to market the office spaces. On the other hand, tenants have not had a tool to demand certain indoor conditions. The paper aims to present one market mechanism for including IEQ in office space supply: the office lease contract model entitled Indoor Environment Quality.

The research included a constructive search for a lease contract model for the problems presented above. The need for this novel lease model is proved by the financial calculations.

The lease contract procedure whereby a lessor issues a condition guarantee to a tenant consists of: technical building audit process; and entering the terms of the indoor condition guarantee in the lease contract. It makes sense for the owner to invest in a favourable indoor environment if the benefits are shared. An owner's monetary benefit from improved IEQ is also greatly related to longer lease periods. When tenants stay longer in the same facility there is less empty office space and less need for alterations by new tenants. Therefore, rental income is higher and alteration costs are lower, which in turn lead to higher profitability of the property owner's business.

The lease model proposed forms guidelines for taking account of the indoor air quality in lease contracts.

Many countries the world over continue to grapple with issues of thermal discomfort both within and without – a condition that has arisen due to incessant urbanization, climate change, among others. The current study focussed on assessing the level of thermal stress both in and outdoors towards finding measures to reduce overheating in spaces within the Savannah climatic region of Ghana through a four-stage approach.

A four-stage approach has been used for the study; thus, a thermal comfort analysis based on physiologically equivalent temperature (PET), overheating assessment, a subjective thermal responses/evaluation of residents and a simulation effort to improve comfort.

There was an indication of “moderate cold stress to slight cold stress” on the coolest day (28th December). On the warmest day (12th April), however, the indoor environment had exceedance and severity of overheating of at least 56% and 38-degree hours. The acceptable comfort range and comfort temperatures of occupants of buildings in the study area have been determined to be 25.5–33 °C by the thermal sensation survey. Meanwhile, the simulation showed that a 200% increase in thermal mass, exterior wall insulation and roof extension and insulation has the potential to generate a reduction of 18% in overheated hours.

The paper unearths the flagrant disregard for thermal comfort in an attempt of “copying blindly” architecture from Southern Ghana by the affluent within the Savannah Region. Again, data provided prove that indeed human activities have worsened the plight of inhabitants through materials as well as construction methods.

The purpose of the paper is to demonstrate that it is completely rational to invest in climate installations for offices designed on the highest comfort category.

By means of a study on a building model it is proved that the benefits of a higher comfort category outweigh the costs of the additional investment, with marginally higher energy costs for cooling.

Depending on the type of climate installation and the comfort class, the additional investment costs can be recovered within six month to two years, due to a higher level of comfort and raised productivity.

The relationship between the thermal environment and productivity makes it possible to design on the basis of productivity improvement, resulting in a comfortable working environment and a consistent financial advantage for the organisation. If the indoor environment is henceforth assessed in the context of comfort and productivity, the participants in the housing process who are generally less interested in the aspects mentioned above will eventually incorporate investments in the quality of the workplace in their objects (in connection with the ability to sell and lease real‐estate).

The paper aims to clarify the relationship between energy flexibility and building components and technologies. It determines the energy flexibility potential of buildings in relation to their physical characteristics and heat supply systems with respect to external boundary conditions.

The emphasis of the evaluation is based on the timing and the amount of shiftable and storable thermal loads in buildings under defined indoor thermal comfort conditions. Dynamic building simulation is used to evaluate the potential of selected building characteristics to shift heating loads away from peak demand periods. Insights on the energy flexibility potential of individual technologies are gained by examining the thermal behaviour of single-zone simulation models as different input parameters are varied. For this purpose, parameters such as envelope qualities, construction materials, control systems for heating are modified.

The paper provides a comprehensive understanding of the influence of the different building parameters and their variations on their energy shifting potential under “laboratory conditions” with steady boundaries. It suggests that the investigated boundary conditions such as outside temperature, infiltration, envelope quality and user behaviour, which influence the heating load of a building, also influence the resulting potential for energy flexibility. The findings show that the combination of a slowly reacting heat transfer system, such as concrete core activation and a readily available storage mass in the room, and a high insulation standard proved to have a high potential to shift heating loads.

In this paper, energy-flexible components were evaluated in a steady-state simulation approach. Outside temperature, solar irradiation and internal loads over the simulation duration were set constant over time to provide laboratory conditions for the potential analysis. On the basis of both duration and performance of the load shifting or storage event, the components were then quantified in a parametric simulation. The determined energy flexibility is directly related to the power of the heating, cooling, hot water and ventilation system, which can be switched on or off. In general, it can be seen that high power (high loads) demand usually can be switched on and off for a short duration, and low power demand usually for a longer duration. The investigated boundary conditions such as outside temperature, infiltration, envelope quality and user behaviour, which influence the load of a building, also influence the resulting potential for energy flexibility. Higher insulation standards, for example, lead to lower loads that can be switched on or off, but increase the duration of the event (flexibility time). So that, in particular, the shiftable load potential is low but results in a long switch-off duration. Furthermore, passive storage potential in buildings like the storage mass inside the room and the type of heat/cooling transfer system can affect the flexibility potential by more than three times. Especially the combination of a high storage mass and a concrete core heat transfer system can significantly increase the flexibility.

The development of strategies for energy efficiency optimization in buildings has become a fundamental way to reduce buildings’ environmental impact because the amount of energy consumed by buildings is responsible for one‐third of total global energy consumption. The purpose of this research is to evaluate the performance of buildings in terms of their indoor operative temperature dynamics considering the impact of other neighbouring buildings. The goal of the paper is to verify whether close spatial relationships of buildings and urban morphology within a local network of buildings could cause a considerable effect on indoor thermal behaviour.

The authors simulated buildings in an existing city block in Albany, New York, USA. The block consisted of six single‐family houses.

The results demonstrate that buildings mutually impact the indoor thermal behaviour of other buildings in the network with indoor operative temperature differences of over 20 percent in summer and over 40 percent in winter for the test case examined. The research also compares this result with improvements in indoor operative temperature achieved through traditional envelope improvements. It was found that during the summer, certain envelope improvement strategies have nearly the same impact in terms of indoor thermal behaviour. During winter, the presence of neighbouring buildings causes a variation that is more than double the value of the effect caused by a typical envelope modification.

It is concluded that this mutual impact on indoor operative temperature across spatially proximal buildings should be included in dynamic analyses of buildings. Future research should examine the effect of these indoor operative temperature deviations on the energy performance predictions of buildings in urban and quasi‐urban settings.

This study investigates the relationships between the built environments of learning commons and user productivity, such as collaborative and individual work productivity and overall environmental satisfaction.

A case study was conducted in a learning commons building at a higher education campus in the USA. The data collection and analysis were conducted with the survey responses of satisfaction with indoor environments and perceived productivity as well as the objective indoor environmental quality (IEQ) measurements. Statistical analysis was performed, including descriptive analysis, principal component analysis (PCA), regression analysis and ANOVA test.

The study presents that satisfaction with noise level is positively associated with individual productivity. The results imply that the spatial properties of open-plan commons, such as visibility and accessibility, are associated with space users' interactions and collaborative productivity. Overall satisfaction is in a positive relationship with lighting satisfaction, study supporting artifacts and furniture configuration. The results of this study reveal the importance of meeting the standards in IEQ factors on individual productivity and the spatial features preferred by space users that facilitate tasks and activities.

The mixed-method approach, including subjective and objective data collection of IEQ, is rarely utilized to show the relationships with perceived productivity. This study investigates a unique building design feature such as step seats in relation to space use and perceived productivity. The findings inform library leadership about environmental characteristics related to the user experience in learning commons, a new format of academic libraries.