The Suitability Analysis of Land Use and Building from BIM to Spatial Detail Plan

The development in urban areas will continue to occur, such as the construction of settlements, offices, shops, educational and health facilities, and other supporting facilities. With the development that will always continue to occur in a nation, it will also increase the productivity in its city. The rapid development of urban activities will also followed by high demand for land. This can lead to land conversion. Therefore, it is necessary to use the land to its optimal capacity and manage it wisely in order to produce a quality space that is maintained for its sustainability. Rules and regulations are compiled into a plan in the Guidelines for the Preparation of Detailed Spatial Planning (RDTR). This research conducted in North Gandaria Urban Village because the buildings are divided into three environments, namely densely populated settlements, middle to upper settlements, offices and shops which based on geometrical aspects have various building forms from small to large ratios. Each building has different diverse land and building usages. In this study, land use suitability was identified by manual and digital classification, namely by image interpretation and classifying using the Object Based Image Analysis (OBIA) method on SPOT-7 images which were then superimposed to produce land use maps. In addition, this study utilizes altitude data from LiDAR to complement building spatial data and is processed to BIM. BIM dimensions are made in 3D with Level of Development 100 or equivalent to Level of Details 1 which has a flat roof if converted. From this research resulted suitability of land use and buildings to carry out an analysis related to sustainability and can be used as consideration and input by the policy makers on spatial planning policies. Based on the results of the analysis, it was found that the suitability of land use was 95% classified suitable to spatial detail plan. To determine the suitability of the building in this study, it was seen from the activities of the building and the height of the building. Based on building activities, 9.30% of building activities that are not allowed and another 90.70% are classified as conditionally allowed buildings, allowed, limited alowed and limited and conditional. Meanwhile, based on the height of the building, there are 82.7% of buildings that comply with the spatial detail plan.

Extensive Roof Greenery as a Response to Heat Islands: Some Problems

Extensive roof greenery is one of the ways to reduce the extent and impact of urban heat islands. A prerequisite is the correct design and operation of both the structural and vegetation part of a roof. If adequate maintenance, especially irrigation of the greenery, cannot be ensured, the use of extensive roof greenery can also be counterproductive. The case study to be presented deals with problems of a flat roof with extensive greenery above an underground garage under Central European climate conditions. Infrequent irrigation leads to extremely high temperatures of the substrate in the summer and makes the purpose of this roof pointless. The contribution analyzes the reason for the failure of the vegetation part of the roof, which was claimed to be maintenance-free, points out fire safety issues, and suggests improvements that might be considered in similar cases. At the present time, which is marked by the climate change crisis, there is great societal pressure to build green roofs. However, if it is not possible to ensure their perfect functionality, it is perhaps better to use classically proven types of roofs, but with greater reflectivity of the top layer surface.

Moisture Risk Analysis for Three Construction Variants of a Wooden Inverted Flat Roof

The paper presents an analysis of the hygrothermal performance of an inverted flat roof with a CLT (cross-laminated timber) structure in a building that meets the requirements of Passive House Standard (PHS) with regards to the potential risk of moisture. The calculations were made in the WUFI®Plus and WUFI®Bio software. The following variants were taken into account: three structure configurations, three different external climates and different scenarios of microclimate control and air change rate. The results of the calculations show that, especially in cooler climates, there is an actual moisture risk in the structure despite the excellent thermal insulation. The structure of the inverted flat roof, due to the use of a tight membrane on the outer side, allows for the partition to discharge the excess moisture only to the inside of the building. Ensuring the comfort of users may require periodic humidification of internal air, which translates directly into an increase in moisture content of the structure. The performed analysis clearly showed that there are no universal solutions. It is important to point out that for the proper performance of inverted wooden roofs, it is crucial to analyse moisture, not only thermal and energy parameters.

Experimental Study of Interference Effects of a High-Rise Building on the Snow Load on a Low-Rise Building with a Flat Roof

To explore the interference effects of a high-rise building on the snow load on a low-rise building with a flat roof, a series of wind tunnel tests were carried out with fine silica sand as a substitute for snow particles. The effects of the height of the interfering building and the distance between buildings on the snow distribution of the target building under three different wind directions were studied. The snow depth on the target building roof and the mass of particles blown off from the target building were measured during the wind tunnel tests, and the results showed that the snow distribution of the target building roof tends to be uniform when the interfering building is located upstream of the target building due to the shelter effect. When the interfering building is on the side of the target building, the snow distribution of the target building tends to be more uneven, because the interfering building increases the friction velocity on the target building roof near the interfering building. However, when the interfering building is located downstream of the target building, there will be an amplification effect of snow accumulation, and the snow distribution on the target building roof is nearly the same as that of the isolated condition. Under each wind direction, the interference effect of the snow load increases with the increase of the building height and the decrease of the building spacing. Therefore, the influence of the surrounding buildings on the snow distribution of the building roof cannot be ignored and should be considered in the structure design.

Impact of roof geometry on cross-ventilation in vaulted buildings: a CFD study

The roof geometry is an important parameter in determining the natural cross-ventilation in buildings. Although many studies have been performed on natural ventilation, the impact of the large set of vaulted roofs on the building cross-ventilation remains to be addressed. In this paper, high-fidelity computational fluid dynamics (CFD) simulations, validated with experimental data, are performed on five naturally ventilated buildings with two opposing windows, each with a specific type of vaulted roof and otherwise identical, in 0° incident flow angle, to assess the impact of vaulted roof geometry on the building cross-ventilation performance. The following vault geometries are investigated and compared against a flat-roof building with the same specifications: (i) segmental, (ii) low-rise pointed, (iii) mid-rise catenary (iv) high-rise pointed and (v) high-rise catenary. The results show that compared to the flat-roof building, the vaulted roofs cause a <5% decrease in volume flow rate and 16-29% increase in the average mean velocity magnitude at the occupants’ level. In vaulted buildings, the low-velocity regions of the flow are moved further away from the occupied zone towards the ceiling, thus providing a fresher air to the occupants. The results clarify the high potential of vaulted roofs for natural ventilation and sustainable design.