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Purpose This study aims to evaluate The Springs’ indoor environment, one of the iconic townhouse-type residential buildings in Dubai, more efficiently for the integrated evaluation of the indoor environment with the weights of indoor environmental factors such as thermal, indoor air, lighting and acoustic. Design/methodology/approach The weights of the indoor environment factors were derived for the integrated evaluation to reflect the residents’ preferences. Based on the post-occupancy evaluation (P.O.E.) survey, the weights according to the gender, age group and indoor spaces followed a comparison and analytical processes. Findings This paper had found the priority of residents’ needs for each space in The Springs project. In summer, thermal comfort was the most important factor for living room and the master bedroom. In winter, the priority for living room and kitchen was the indoor air quality. Research limitations/implications As it is the first research survey for housing project in Dubai, it needs to be extended to other housing projects in Dubai. To increase the reliability of the weights calculated through this study and the applicability of the integrated indoor environmental evaluation, more in-depth P.O.E. survey is needed with wide range of survey participants. Social implications This paper will help developing guidelines for future renovation based on the comparative analysis among thermal comfort, acoustic comfort, lighting comfort and indoor air comfort. Originality/value This paper is the first attempt to analyze the condition of early housing projects in Dubai. The data can be used to increase not only the design quality and marketability of housing projects in Dubai but also the condition of residents’ health status to avoid sick building syndrome from approximately 20 years old buildings.

-Sustainability in architecture must produce buildings that give satisfaction for people with less energy consumption and less environmental problems. The sustainable design in architecture adopts passive design strategies like courtyards that produce buildings which use the wind for cooling and the sun for lighting and heating. The courtyard was a climate responsive design in the past, that provided people with easy direct solutions for their problems with the climate, and it was able to satisfy their social needs. In this study there will be an investigating for the effect of closed courtyard with different proportions on school building in UAE, to test the capability of the closed courtyard in improving the thermal performance of the school building consequently minimize the energy consumption. The study adopted a school building as a case study because courtyards are used mostly in houses while it can be beneficial for public buildings like schools. Courtyard can provide the school with private outdoor space, and can improve the thermal and ventilation properties of the school building thus minimize the energy consumption. Moreover the courtyard can provide the school with safe inner playground and learning scientific atmosphere for the students. The study will adopt a qualitative methodology which depends on descriptive and comparative analysis for the case study after the computer simulation with the Integral Environmental Solutions software (IES). After investigating the case study with different courtyard proportions and with the aid of the computer simulation, there was energy savings for the building because of the presence of the closed courtyard but with different values related to the proportions of the courtyard. The final result indicated that the courtyard effects the amount of the sun exposure, solar gain consequently the cooling sensible plant of the building, moreover the courtyard design and proportions have a direct effect on the ventilation beside the thermal performance of the interior spaces. However the courtyard should be in proportions that suits the height and the function of the building.

Sustainable architecture is a key approach for creating sustainable cities and reducing the impact of climate change. In hot, arid regions, the passive design traditional architecture is known for its ability to provide comfortable indoor environments and outdoor shaded areas, in contrast to the use of energy-intensive air conditioners in a great deal of modern architecture. Thus, this research used a qualitative methodology based on ENVI-met software to study, investigate, and compare the thermal performance of two urban fabrics as case studies (traditional and modern districts) in the hot, arid climate of the United Arab Emirates. The thermal performance of the old urban districts was better than the new ones, with a lower maximum potential air temperature and an improvement in the level of thermal comfort, measured by a predicted mean vote. Moreover, it was found that enhancing the shade in the outdoor open areas in the modern district, mimicking the traditional passive design solutions, resulted in lower air temperature and PMVs. This research is expected to be one step among many towards creating sustainable, innovative modern architecture.

The courtyard as architectural passive design strategy has proved its capability of enhancing the thermal conditions of buildings. Apart from the good thermal impacts of the courtyard, there are other effects that were not tapped and need to be explored such as the satisfaction of the courtyard's users in terms of psychological and wellbeing factors. This study attempts to investigate and assess the relationship between the existing design of the school courtyards in UAE with the students' satisfaction. A self-administrated questionnaire was distributed between students of secondary classes in two private schools in UAE to gather the data. Six hypotheses were developed to explore and validate the mentioned relationship; SPSS (Statistical Package for Science Software) program was used to apply several tests such as regression analysis to examine the developed hypotheses. The results showed high relationship significance between the School Courtyard Design and Students' Satisfaction, so that the courtyard design can shape the student satisfaction as global variable with 29.2 %, with many other important findings. The work opens the door for architects and school principals alike to understand the effect of the school courtyard design on students' satisfaction, which consequently leads to better academic achievement.

Heating, Ventilation and Air Conditioning (HVAC) is a multivariable process where any alteration with one system input affects most or all of the system’s outputs simultaneously. Owing to its comprehensiveness, a readily derived multivariable HVAC mathematical model is selected for this work, mainly a hybrid distributed-lumped parameters model. As the transfer function matrix was not established in the selected HVAC model, it was exclusively developed in this study, using the time domain graphical responses of the chosen model. Based on the developed transfer function matrix, a conceptual two-step approach was followed to control HVAC model performance. The first was decoupling the interactions that affect all the system outputs, and the second was designing proper PID controllers for each decoupled loop similar to those used for single input single output (SISO) systems. A direct Nyquist Array (DNA) multivariable control strategy was used for this purpose and successfully decoupled the HVAC system into three separate (SISO) loops. Three PID controllers afterwards were applied for each decoupled loop. The results showed quite decoupled system outputs with a minor coupling percentage so that any change in a system input only affected the corresponding system output. The output responses are also underdamped with almost zero steady-state error confirming the effectiveness of the selected PID parameters. The values of steady-state responses are obtained in (10–15) s compared with (200–600) s of open-loop response time. However, various overshoot percentages in the responses are encountered but are relatively small, with a short settling time, so they don’t affect the thermal comfort of the ventilated volume. System stability using the Nyquist criterion has also been examined and found to satisfy the criterion. The multivariable DNA control technique and the SISO closed-loop PID controllers have shown the capability to suppress external disturbances and restore the system to its original functional steady-state values.

Achieving future energy objectives and promoting social, economic, and environmental sustainability can be inspired by heritage and historic structures, which make up a sizeable component of the existing building industry. Heritage architecture and urban sites are known for their capability of positive interaction with the climate to provide better thermal conditions, beside their capability of strengthening cultural identity and improving the economic sector for the related sites. Thus, the main purpose of this research is to highlight the positive sustainable effects (social, economic and environmental) for a proposal of conserving and reconstructing a vernacular heritage architecture site in the hot arid climate in the UAE. The research used a qualitative methodology based on multicriteria descriptive schemes beside ENVI-met software. The research’s findings presented the capability of the conserved heritage area to strengthen the social and cultural identity and improve the economic sector. Moreover, the results demonstrated that the conserved heritage district had a better microclimate and predicted mean vote for outdoor thermal comfort compared to the basic case heritage district prior to rehabilitation and another modern district. The conclusion promotes heritage conservation in hot arid climates and encourages the preservation of vernacular architecture and traditional sites to achieve the sustainable goals for creating sustainable cities that can mitigate climate change.

Prior to the discovery of electrical power, the buildings in the UAE were built with a concentration on the passive designs in order to have daylight and natural ventilation as well as avoiding the undesired heat. The wind tower was considered as the most familiar cooling strategy followed in the traditional architecture. However, the advanced air conditioning systems of the present time have removed the need for the wind catchers since the indoor comfort could not be achieved enough by the wind towers and at the same level that advanced air conditioning systems can do. Despite the integration of the Green Buildings in UAE, the cheap energy prices and the poor attention to energy efficiency buildings have converted UAE to one of the top ten countries worldwide that have high electricity consumption per capita. This work offers a low carbon proposal to solve the problem and demonstrates three strategies that can be adopted in UAE to implement energy efficient buildings without compromising on the indoor comfort and air quality. IES VE and RETScreen software were used to simulate and analyse the proposed strategies. Using proper wall construction material that has minimum thermal transmittance value is one of the strategies that can be implemented to reduce the airconditioning operating time thus less energy consumption. In addition to its benefits to the urban area, Green Roof is the second strategy that can be also implemented in order to reduce the thermal transmittance value of the roof. The last strategy is to employ Photovoltaic Panels to produce clean energy and to reduce the reliance on the fossil oil-generated power. As an overall, the bundle of three strategies has proved its efficiency to reduce the cooling energy consumption. The total electricity saving was 15.45 (MWh) and with a percentage of 19.6% of the total base case cooling power consumption.