Most new housing designs in Saudi Arabia are created to meet the client’s needs with minimal regard for environmental or energy-related considerations, resulting in buildings’ poor thermal performance and a growing reliance on artificial means. Polycarbonate windows have recently acquired popularity. Yet, there is a rising interest in combining polycarbonate windows with nanomaterials to reduce energy consumption, especially during the summer months when air conditioning use is at its peak. To improve building insulation, this research concentrated on the use of polycarbonate windows with nanogel, which has a low U-value. This study utilized polycarbonate windows with nanogel (two layers of polycarbonate panes filled with nanogel) in Hail City, Saudi Arabia, using DesignBuilder simulation software, resulting in a 14.3% reduction in annual energy consumption. The low U-value of nanogel compared to argon or air may be the cause of these savings, which are roughly double those gained by using double-paned polycarbonate windows. The incorporated nanogel layer between two layers of argon and two layers of polycarbonate panes decreased annual energy consumption by 29% compared to utilizing only one polycarbonate layer. Moreover, compared to a single 3 mm polycarbonate pane, the nanogel layer placed between two layers of argon and two layers of single polycarbonate panes demonstrated the lowest level of CO₂ emissions, with an improvement of around 22.23%. This study reveals a method for insulating buildings that cuts energy use and CO₂ emissions. This study’s conclusion supports the notion that sustainable design is the future. Sustainable construction can dramatically reduce building cooling costs and thermal loads.

Public construction projects in Saudi Arabia are fraught with several challenges threatening open and fair competition, which consequently negatively influence the decision of contractors to participate in bidding. Nevertheless, the construction sector has witnessed rapid reforms since 2016, which have resulted in the issuing of new legislation and regulations as well as the creation of governing bodies. Hence, the concept of open and fair competition plays a significant role in the governance of these challenges in the upstream process of construction tendering. Therefore, this paper explores challenges that are hindering contractors’ participation in the tendering phase of public construction projects in light of these new legislations and authorities. Twelve challenging factors were identified from a structured literature review of previous relevant empirical studies available in online search engines since the 1980s. Those factors were measured through Delphi survey questionnaires, which provided respondents with the option of adding new challenging factors. Thus, twenty factors were identified. A descriptive method was used to determine and prioritize these challenging factors. The survey findings indicate that the most influential hindering factors are (1) awarding contracts based on the lowest bidder, (2) inadequate or incomplete specifications, (3) poor contract documents, and (4) poor cost-estimating practices. These findings are vital in exposing the lack of relationships between the construction industry, regulators, and stakeholders for robust partnerships, thereby helping to ensure the fair participation of contractors, which boosts open and fair competition concepts for public construction projects.

The computational fluid dynamics (CFDs) models based on the steady Reynolds-averaged Navier–Stokes equations (RANSs) using the $k-\omega$ two-equation turbulence model are considered in order to estimate the wind flow distribution around buildings. The present investigation developed a micro-scale city model with building details for the Hail area (Saudi Arabia) using ANSYS FLUENT software. Based on data from the region’s meteorological stations, the effect of wind speed (from 2 to 8 m/s) and wind direction (north, east, west, and south) was simulated. This study allows us to identify areas without wind comfort such as the corner of the building and the zones between adjacent buildings, which make this zone not recommended for placement of restaurants, pedestrian passages, or gardens. Particular attention was also paid to the highest building (Hail Tower, 67 m) in order to estimate, along the tower height, the wind speed effect on the turbulence intensity, the turbulent kinetic energy (TKE), the friction coefficient, and the dynamic pressure.

Over 50% of the total energy consumed by buildings in a hot and dry climate goes toward the cooling regime during the harsh months. Non-residential buildings, especially houses of worship, need a tremendous amount of energy to create a comfortable environment for worshipers. Today, mosques are regarded as energy-hungry buildings, whereas in the past, they were designed according to sustainable vernacular architecture. This study was aimed at improving the energy performance of mosques in a hot and dry climate using bioclimatic principles and architectural elements. To achieve this aim, a process-based simulation approach was applied together with a generate and test technique on 86 scenarios based on 10 architectural elements, with various arithmetic transition rates organized in 9 successive steps. Starting from a simplified hypothetical model, the final model of the mosque design was arrived at based on a holistic bioclimatic vision using 10 architectural elements. The findings of this research were limited to a specific mosque size in a hot and dry climate, but the proposed holistic bioclimatic concept can be developed to take into account all mosque models in several harsh environments.

According to the United Nations (UN), an additional 1.35 billion people will live in cities by 2030. Well-planned measures are essential for reducing the risk of flash floods. Flash floods typically inflict more damage in densely populated areas. The province of Hail encompasses 120,000 square kilometers, or approximately 6% of the total land area of the Kingdom of Saudi Arabia. Due to its innate physiographic and geologic character, Hail city is susceptible to a wide variety of geo-environmental risks such as sand drifts, flash floods, and rock falls. The aim of this work is to evaluate the rate of urban sprawl in the Hail region using remote sensing data and to identify urban areas that would be affected by simulated worst-case flash floods. From 1984 to 2022, the global urbanization rate increased from 467 to 713% in the Hail region. This is a very high rate of expansion, which means that the number of urban areas exposed to the highest level of flood risk is rising every year. With Gridded Surface Subsurface Hydrologic Analysis (GSSHA), a wide range of hydrologic scenarios can be simulated. The data sources for the soil type, infiltration, and initial moisture were utilized to create the coverage and index maps. To generate virtual floods, we ran the GSSHA model within the Watershed Modeling System (WMS) program to create the hazard map for flash flooding. This model provides a suitable method based on open access data and remote data that can help planners in developing countries to create the risk analysis for flash flooding.

Due to urbanization, population growth, and the consequences of climate change, the usage of energy for cooling has increased considerably in recent years. Passive climate measures, on the other hand, could alleviate the situation by reducing energy use in buildings. This study examined the environmental and financial benefits of utilizing glass fiber-reinforced cement in the external walls of a communal social hub building in New Aswan city, taken an example of the hot desert region. Utilizing Design Builder software, the effect of various outside wall alternatives on cooling energy consumption was explored and analyzed. In addition, a cost–benefit analysis utilizing the simple payback period was conducted to aid decision-makers in selecting the most suitable exterior wall materials for public buildings in hot desert regions. Using cement plaster, cement brick, glass wool, and glass fiber-reinforced cement as an outside wall resulted in a significant improvement rate, according to the data. Compared to a typical wall (cement plaster, cement brick, and cement plaster), it can save up to 41% of energy. In addition, it has the lowest simple payback period value when compared to other examined solutions (10.86 years). In general, the results indicate that glass fiber-reinforced cement walls embedded in thermal insulation materials and incorporated into cement brick walls are more energy-efficient in terms of necessary cooling energy and economic viability.