A Geospatial Multi-Criteria Framework for High-Rise Development Site Selection in Dense Urban Areas: Evidence from Karrada District, Baghdad

Rapid population growth and the scarcity of development land have posed a fundamental challenge to the sustainable planning of large cities, particularly in dense urban areas in developing countries [1, 2]. For the purposes of this study, a high-rise building is defined as a building with a height of 50 m or more, consistent with the threshold commonly adopted in tall-building literature [3]. In the Iraqi context, rapid urban growth in Baghdad has been associated with increasing housing demand, unplanned expansion, traffic congestion, pressure on urban services, and spatial concentration of development, highlighting the need for planning approaches capable of accommodating growth while reducing pressure on the existing urban fabric [4]. In light of limited urban land and the desire to find the best use of it, high-rise development is a viable solution to accommodate population growth [5, 6]. Today, these structures are no longer only architectural landmarks, but are increasingly playing a key role in the restructuring of an urban area that is increasingly forced to satisfy the housing, employment, and service needs of urban residents, and enhance the quality of their connection with urban services [7]. In the hot-arid context of Baghdad, previous research has shown that urban form, particularly building height, floor area ratio, building density, and the resulting shading conditions, can significantly influence outdoor air temperature, indicating that the vertical dimension of urban development has important microclimatic implications [8]. The process of selecting suitable sites remains complex due to the multiplicity of spatially interacting factors within urban systems, such as economic and social processes, transportation routes, infrastructure, and connectivity to the urban fabric of the parent city [9, 10]. In the Iraqi urban context, previous research has also shown that density, accessibility, social interaction, and the distribution of activities are important dimensions influencing the performance and vitality of urban spaces [11]. Other evidence from cities in Iraq also shows that accessibility, spatial resilience, and social interactions are relevant planning and evaluation criteria for urban spaces, especially when evaluating the impact of (spatial) interventions in the distribution of urban opportunities and benefits [12].

In dense areas, high-rise buildings are effective in land use planning. On the one hand, they represent an effective solution to the problem of land scarcity, as they allow for accommodating larger populations and economic activities within a relatively small geographic area, thus contributing to the preservation of open land and green spaces outside the core urban area. Concentrating activities in high-density centers also increases the efficiency of public transportation networks and infrastructure and reduces reliance on private vehicles. Studying the factors affecting the planning of these structures within the framework of achieving spatial sustainability represents a clear challenge [13]. The introduction of a high-rise building into an existing urban fabric can impact traffic flows, local environmental conditions (such as shade and wind flow), and the capacity of water, sewage, and energy networks to accommodate additional loads [14]. However, these detailed factors often operate at the site or plot level, and therefore should be distinguished from the strategic spatial screening criteria used to identify primary priority areas.

Therefore, the decision to select the optimal location for such projects is not simply a matter of filling an urban void or remodeling existing buildings. Rather, it is a vital strategic decision that requires in-depth study and integration of various social, economic, urban, and environmental factors [15].

Hence, the search for and development of spatial analysis tools to understand urban processes and the interactions involved in the site selection of high-rise buildings has emerged [16].

Although previous literature has presented various models linking spatial analysis and multi-criteria decision-making methods for evaluating high-rise building sites, their application remains highly dependent on the nature of the urban context, data availability, and local planning constraints. Furthermore, their application is limited in the context of densely populated Iraqi cities, where land use patterns and values, population densities, transportation characteristics, and availability of developable land differ from the contexts in which most previous models were tested. Therefore, the research need lies in adapting these approaches to local characteristics and transforming available planning considerations into evaluable and comparable spatial criteria.

Paszkowski et al. [17] investigated the role of tall buildings in achieving sustainable urban development, taking the Hansa Tower in Szczecin (Poland) as a case study. The issue is how to evaluate the interaction of such modern constructions with the current urban fabric and the effects that they have on post-industrial spaces. The purpose of the study is to analyze and evaluate the impact of the tower from a functional, spatial, and social point of view. A qualitative methodology based on spatial and architectural analysis was adopted, focusing on social, functional/technical, and aesthetic/formative aspects. The results indicate that the tower represents an important element in the modern urban fabric, contributes to the revitalization of the area, and has great potential for achieving sustainable development.

In this context, Utami et al. [18] noted that the Indonesian city of Medan lacks a three-dimensional map of the distribution of high-rise buildings, and there is an urgent need for urban spatial planning maps for these buildings. The research aims to create a map of the distribution of high-rise buildings in the West Medan sub-district and assess their compatibility with the service center areas in Medan. The methodology used a model integrated into ArcGIS, with high-resolution imagery data from SAS Planet and GPS coordinate data for high-rise buildings with more than four floors. The results showed that the distribution of high-rise buildings conforms to a relatively sparse and dense pattern in the West Medan sub-district, which is a center for commercial/business services, government services, and the economy.

Regarding environmental impacts, Weng and Zhuang [19] pointed to the problem of high-rise development in New York City and the impact of air rights policies on this development. The aim is to reveal the relationship between air rights policies and the evolution of high-rise urban block patterns, providing a reference for future policymakers. The methodology relies on extensive spatial analysis using Geographic Information Systems (GIS) to link building locations and apply air rights policies, as well as using Space matrix criteria to analyze urban density through zoning. The most critical results show that air rights methods (zoning lot mergers, transfers to special districts) played a key role in the development and the morphology of high-rise buildings in different stages throughout Manhattan.

Mohamed et al. [20] developed a spatial analysis model for the allocation of high-rise buildings by integrating GIS with the Analytical Hierarchy Process (AHP). The study incorporated several spatial criteria related to urban characteristics and used them to evaluate the relative suitability of different locations for high-rise development. The study demonstrates the applicability of GIS-based multi-criteria analysis for supporting high-rise building site allocation decisions in urban areas.

Munn and Dragićević [21] proposed a three-dimensional weighted linear combination multi-criteria evaluation (3D WLC-MCE) method for assessing the suitability of residential units within high-rise developments in dense urban environments. Applied to the City of Vancouver, the approach evaluated alternative preference scenarios using spatial criteria that vary vertically within buildings. The results showed that the suitability of residential units can differ according to floor level, orientation, exposure to road-related noise and pollution, sunlight access, and views. The study demonstrates the potential of extending conventional GIS-based multi-criteria evaluation into a three-dimensional urban context to support planning and assessment of vertical development.

Mansouri Daneshvar et al. [22] discussed the problem of land suitability assessment for constructing high-rise buildings in urban sustainability in the Iranian city of Mashhad by proposing an integrated land suitability assessment methodology based on the GIS and ANP approaches. A broad spectrum of indicators based on economic, social, natural, environmental, infrastructure, and environmental services is analyzed. The results indicate that there are low suitability zones in the city even though it has a large number of high-rise buildings due to seismic fault lines, steep slopes, and flood risk in the respective areas. The research validates the fact that such a current trend is really not in line with natural sustainability in such areas.

In analyzing the evaluation process for high-rise buildings for suitable sites in the urban space of Vilnius, Tamošaitienė et al. [9] studied experiences of other European cities. A multi-stage evaluation model based on a combination of three decision-making procedures, SWOT analysis, the determination of the weights of criteria using expert judgement, and the simple additive weighting method (SAW) to rank the alternatives was developed. The results show that the three methods above are able to reduce the identification of high-rise building locations and contribute to balancing the management's goal and the real estate market.

This paper addresses this issue by applying a multi-criteria geospatial framework that combines spatial analysis and GIS, while adapting the selection criteria and their weights to the local characteristics of the Karrada District in Baghdad—a model for high-density cities in Baghdad—which then becomes a relevant test case, exposing the model's possibilities to solve real city problems. This paper contributes to identifying a set of local planning considerations and transforming them into measurable and comparable spatial criteria within a unified model to support the strategic spatial assessment of high-rise development sites. Furthermore, combining spatial criteria into a single model provides a more comprehensive basis for comparing sites compared to relying on a single indicator.

Finally, the relative weights of the criteria can be adapted when applying the approach in other urban contexts, depending on local characteristics and data. This research can go beyond the particular local "solution" to make a tangible contribution to the theme "sustainable urban growth management". The framework provides a tool for initial spatial screening that helps planners identify areas worthy of further detailed studies, with the possibility of adapting its criteria and weights according to the characteristics of the urban context in which it is applied.

Table 1. Number of neighborhoods for Karrada quarters

Additionally, the area is home to numerous universities, the most prominent being the University of Baghdad and the University of Nahrin, and it includes a variety of diverse uses such as commercial centers, factories, public services, and more (Table 2 and Figure 5).

There is also an extensive network of various transportation routes, with the total length of highways measuring 16.89 km, main roads 102.14 km, and secondary roads 112.9 km [42, 43].

The scarcity of high-rise buildings in Baghdad and the Karrada District, despite its strategic and attractive location, is due to many reasons, including:

1). The absence of a comprehensive plan for the construction of high-rise buildings, the absence of building regulations and laws that permit their construction, and the setting of height limits that do not exceed certain limits.

2). The failure to update the general plan for the city of Baghdad to ensure the construction of this type of building.

3). The lack of interest from the public and private sectors in constructing this type of building.

4). The lack of sufficient land in the city center.

5). The need for sufficient parking spaces, adequate road capacity, and appropriate infrastructure services should be considered in planning high-rise development, particularly in Baghdad, where previous research has demonstrated that changes in urban land use can substantially increase parking demand and traffic pressure [44].

6). The lack of sufficient local technology and expertise, and the need for foreign expertise in this field.

Table 2. Land use areas and their percentage for the Karrada District in the city of Baghdad

Figure 5. Land use distribution of the Karrada District in Baghdad

3.3 Data sources and spatial database setup

As for the data sources, we relied on the literature related to the subject of the study, both in the conceptual aspect and the applied framework, as the data were collected for the study area from different directorates and departments such as the Karrada Municipality and the Baghdad Municipality, in addition to the Central Statistical Organization in the Ministry of Planning; GIS was used to generate relevant complex data such as population densities and other sources available in scientific articles and published in global containers regarding the study area. The study period was April to October 2025, and the necessary data for the study were collected. The data included land uses, road networks, population, natural and historical sites, seismic activity zones, commercial centers, land values, and undeveloped and buildable land. These data represent the actual inputs to the current model, whereas detailed data on geotechnical characteristics, groundwater, flooding, network capacities, elevation constraints, regulation, and ownership were not targeted with sufficient uniform spatial accuracy to be included in the comparison model at the study area level. These were not included as they would be addressed during the site-level verification process at a detailed level, which is not part of the present strategic screening model. The data were entered into a GIS environment, and the coordinate system and spatial accuracy of all layers were standardized. Data were subsequently checked, geometric and topological errors were edited out, and the boundaries of the layers were checked to correspond to the study area boundaries. If data were in descriptive form or paper form, then it was digitized and georeferenced to the spatial location. All the layers that were utilized in the analysis were then assembled in a single spatial database.

3.4 Identifying suitability factors and criteria

The criteria that affect the selection of high-rise building sites were determined by literature, study area characteristics, and experts' opinions. These criteria were put into four broad categories, namely, environmental factors, social factors, economic factors, and physical factors. Two environmental factors were considered: distance from natural/historical sites, and distance from seismic activity areas. The social factor was represented by proximity to areas with low population density. Economic considerations were distance from existing commercial centers and distance from high-value land. Physical factors included closeness to major transportation systems and closeness to undeveloped/buildable land. Before the analysis, the directionality of the influence of each criterion was determined – the higher the value for a site, the “more suitable” the site was; the lower, the “less suitable.” For criteria representing sources of risk, sensitivity, or cost, such as seismic activity zones, natural and historical sites, and high-value land, suitability increases with distance. Conversely, for criteria related to accessibility and land availability, such as main roads and undeveloped buildable land, suitability increases with proximity (Table 3).

The current model does not use a separate layer for legal or exclusionary restrictions. Therefore, the resulting classification represents a relative spatial suitability according to the seven criteria, not a final judgment on developability. The transition from spatial suitability to development feasibility requires subsequent examination of military lands, protected areas, riverbanks, heritage sites, orchards, and legally restricted lands. Also, the current model is limited to a strategic spatial assessment using criteria that can be consistently represented spatially at the area study level. It does not aim to provide a final plot-level evaluation or issue a direct construction decision. Therefore, some detailed constraints requiring high-resolution site or regulatory data, such as geotechnical properties, groundwater depth, flood risk, flight height restrictions, capacity of water, drainage, energy, road, and public transport networks, fire service access, plot geometry, ownership, regulatory controls, building coefficients, wind and shading effects, and privacy, have not been incorporated. These factors must be verified at a later stage before moving from spatial suitability to actual development viability.

Table 3. Direction of preference and suitability function for the selected criteria

3.5 Determining the weights of criteria using hierarchical analysis

The research used the AHP to find out relative significance among criteria. This has a benefit as it brings organization to the decision problem, enables the criteria to be considered on a pairwise basis, and checks the logical consistency of the decisions taken. In this context, seven experts who have relevant expertise in the field of the study participated. These disciplines comprised urban and physical planning, GIS, transportation planning, environmental planning, civil engineering, and real estate development. The experts were selected based on their expertise in land use, urban development, suitability assessment, and site selection. Each expert was asked to compare the seven criteria pairwise using the Saaty scale, which ranges from 1 to 9. A value of 1 indicates that the criteria are equally important, while values 3, 5, 7, and 9 indicate moderate, strong, very strong, and maximum importance, respectively. Values 2, 4, 6, and 8 were used to represent intermediate cases, while inverse values were used when a row criterion was less important than a column criterion. Since the number of criteria was seven, the number of independent pairwise comparisons performed by each expert was 21, according to the relationship:

$N=\frac{n(n-1)}{2}$

Figure 6. GIS–AHP methodological workflow for high-rise development site suitability assessment

Vertical development priority areas were identified and highlighted by the high and very high categorization. None of the identified areas should be interpreted as being immediately suitable for construction. The map is used to screen sites strategically, and the chosen sites would need more detailed investigations into issues such as land ownership, capacity of the infrastructure network, geotechnical properties, traffic impacts, planning and construction controls (Figure 6).

The current model does not use a separate layer for legal or exclusionary restrictions. Therefore, the resulting classification represents a relative spatial suitability according to the seven criteria, not a final judgment on development feasibility. The transition from spatial suitability to development feasibility requires subsequent examination of military lands, protected areas, riverbanks, heritage sites, orchards, and legally restricted lands.

3.9 Expert-based validation of the suitability results

To verify the planning plausibility of the suitability model outputs independently of the weighting process, the final suitability map and its five categories were presented to a panel of experts who had not participated in the pairwise comparisons used in AHP. They were asked to assess the extent to which the spatial distribution of the categories corresponded to the known characteristics of the Karrada District, the plausibility of the locations classified in the high and very high suitability categories, and the map's suitability as a tool for strategic spatial screening. The assessments were recorded using a five-point Likert scale ranging from 1 (Very Low Agreement) to 5 (Very High Agreement).

For the study design, five experts, independent of the seven experts involved in the AHP weighting process, participated in the validation procedure, as shown in Table 9.

Table 9. Professional background of the independent validation experts

The five experts were presented with the final suitability map, the five suitability categories, and the seven criteria used in the model and their relative weights. It was clarified that the highly rated areas did not automatically qualify for development but were instead priority areas for detailed planning examination. Next, the experts were asked to review the outcome of the exercise on the overall plausibility of the spatial distribution, areas classified as high suitability, areas classified as very high suitability, connection with the planning, transportation, and environmental characteristics of the study area, as well as suitability for the model to support strategic spatial screening using an eight-item questionnaire. The full validation tool is included in Table A3.

The expert ratings were analyzed using the arithmetic mean and standard deviation for each validation item, together with the overall mean score, to assess the planning and spatial plausibility of the model outputs.

The interrelationships between the seven criteria were discussed taking into consideration the nature of the Karrada District and the level of optimal development site selection that can be supported by the proposed spatial framework in dense urban areas. The suitability map should not be read as an absolute map of buildable plots, but rather a tool for a strategic spatial analysis that helps to focus the analysis and pinpoint areas that warrant further analysis. It can support the selection of high-value development sites within dense urban areas.

5.1 Significance of spatial variation in suitability levels

The results showed that spatial suitability for high-rise development was not uniformly distributed within the Karrada District, but rather resulted from the complex interaction of the studied criteria. This variation shows that individual criteria, such as being close to main roads and low land value, can be limiting factors in determining where high-rise buildings are located.

Therefore, the largest area in the study was almost occupied by the medium suitability category with 4,499.29 ha or 60.35% of the total area of the study. This category dominates for Karrada, which is intentional, to some extent causing it to lose out on a large share of the aspirations of a high-rise development, but it also doesn't have all the preferred qualities to the extent needed to qualify it as a top priority. While they may be located near transportation or away from certain hazards, one or more of these sites may be subject to high land value, high population density, and/or limited availability of undeveloped land.

Sites that qualified for high suitability, on the other hand, amounted to 1,707.26 hectares or 22.90% of the total area, and very high suitability sites amounted to 506.13 hectares or 6.79%. The total area of these two zones was 2,213.39 ha, accounting for about 29.69% of the study area. The percentage reflects an important spatial bottom and allows for future vertical growth studies. Not all of this area is necessarily available for building projects, however, as some of these pieces of land may have existing uses and others may be unavailable for site development or in need of detailed examination of the capacity of the water, sewage, energy, and transportation systems.

The low and very low sites totaled 742.04 ha or ~9.96% of the study area. Most of Karrada is not absolutely spatially constrained: the percentages of these categories are lower than others, indicating this. But this does not preclude the presence of sensitive areas in which development is not recommended because it places the development at high risk, for example, areas close to natural and historic features, areas impacted by hazards, areas with limited accessibility and/or land availability.

This discovery supports the need to adopt a hierarchical approach, instead of sorting into just two categories: suitable and unsuitable locations. This realistic planning in built-up areas is not necessarily land free of all constraints, but rather a selection of various levels of suitability and then an action plan to fill all the gaps in each. This means that the medium category may be considered to be a conditional planning reserve, and high and very high categories as the primary planning areas for study detail.

5.2 Interpreting the relative importance of the criteria

Through the use of AHP, the characteristics of proximity to undeveloped and buildable areas were found to be the top one, followed by a weight of 20%. This is because the availability of land is a necessary condition for a feasibility study in the development of high-rise buildings; for instance, in areas where high buildings overlap and where land is already utilized, the demolition and redevelopment expenses are very high. If a site has good accessibility or is near some of the services, but there is not a suitable plot on the site, then development can become more complex, and it can be less viable. The focus on undeveloped land does not imply that development can be encouraged at the cost of agricultural land, orchards and/or environmentally sensitive places, as these are accounted for in a separate criterion which impacts the suitability of nearby sites. This reveals the balance the model attempted to achieve between ease of development on the one hand and the protection of natural and historical resources on the other. This distinction is particularly important in the study area because of the presence of military, environmental, and heritage uses that may appear spatially as undeveloped land, but cannot automatically be considered land available for development. Therefore, the high degree of suitability in the model does not negate the need for subsequent verification of the land's legal and regulatory status. The criterion of avoiding high-value land ranked second, with a weight of 16%. This weight reflects the importance of economic feasibility in selecting sites for high-value projects, as high land prices increase the initial project cost and may lead developers to excessively increase building density to offset acquisition costs. However, the preference for lower-value land does not necessarily mean choosing peripheral or isolated locations. The criterion of proximity to major transportation routes counteracts this trend and ensures that proposed sites are connected to the urban transportation network. The criterion of proximity to low-density areas ranked third, with a weight of 15%. This is due to the desire to ensure that no added urban stresses are imposed on neighborhoods already under strain and that are already highly built. Low density should not be the only measure of capacity, though—some low density areas might be lacking in infrastructure, or services are hard to reach. Creating networks and infrastructure to support this development, then, calls for checking population density—along with the actual capacity of networks already on the books. Distance from seismic activity zones was weighted at 14%, and this is important because, in the design of high-rise buildings, it is very important to have safe building directions, as the loads, foundation requirements, and sensitivity to ground movements differ from those of conventional buildings. The criterion, however, is a general spatial assessment and is not intended to be a substitute for detailed site-level geotechnical and seismic studies; the suitability of a proposed plot will also be influenced by the type of soil, the depth of the water table, the bearing capacity, and the foundation system to be adopted. The proximity to main transportation routes was given a weight of 13%, as accessibility and connectivity to the rest of the city was an important factor. Proximity to major thoroughfares can enhance accessibility, and these are likely to have a higher level of trips for high-rise buildings, whether residential or commercial or a hybrid of both. But being close to a road doesn't necessarily mean there is adequate traffic volume; however, if the sites are not provided with public transportation, adequate access points, good design of parking facilities, and a comprehensive traffic impact analysis, high-rise development can have a negative impact on traffic. Distance from the already existing commercial centers was weighted at 12%. This is because people want to alleviate the lack of balance in the distribution of activities in current centers, and promote the development of new clusters. However, excessive distance can result in poor connections to activities and services. Hence, centers should not be encouraged to be located away from the urban fabric through this criterion, but rather as a way to support a balanced distribution of centers. Distance from natural and historical sites received the lowest weight, at 10%. This does not imply that these sites are unimportant, but rather that their relative weight was lower compared to other operational and economic criteria within the decision model. Peaceful preservation of orchards, areas of agriculture, banks of the Tigris River, and areas of heritage are fundamental requirements. Some elements, such as protected areas, riverbanks, heritage sites, and legally restricted lands, may be best treated in subsequent studies as non-compensable exclusionary constraints, rather than allowing their lower suitability to be compensated for by high scores in other criteria. Looking at the ranking of criteria overall, it seems that experts gave due consideration to the density, safety and accessibility criteria and that spatial and economic considerations (land availability and value) were considered more important. This approach endows the model with a practical feel and, at the same time, allows for the weights not to be seen as fixed values which apply to all cities—priorities may shift in other cities based on the extent of natural hazards, land availability, mode of transport, planning restrictions, etc.

5.3 Weight robustness and ranking stability

To evaluate the stability of criterion priorities under the ±20% weight perturbation scenarios described in Section 3.7, Spearman’s rank correlation coefficient was calculated for each scenario relative to the baseline ranking (Table 12).

Table 12. Spearman rank correlation results for weight-robustness scenarios

The 14 scenarios were calculated based on the baseline weights in Table A1, where C1 = 10, C2 = 14, C3 = 15, C4 = 12, C5 = 16, C6 = 13, C7 = 20.

Therefore, the baseline order is: C7 > C5 > C3 > C2 > C6 > C4 > C1 (Table 12).

Weight robustness analysis revealed a high level of stability in the ranking of criteria across the fourteen scenarios. Spearman's correlation coefficients ranged from 0.786 to 1.000, with a mean of 0.918 and a median of 0.964. Criterion C7 maintained its first ranking in thirteen out of fourteen scenarios and only moved to second place when its weight was reduced by 20%. The largest relative changes in ranking occurred when the weight of C3 was reduced, the weight of C5 was reduced, and the weight of C6 was increased, although the correlation coefficients remained relatively high. These results indicate the robustness of the weighting structure and the stability of the overall priority of the criteria within the assumed range of change, and do not represent a test of the stability of the spatial distribution of the suitability categories.

The modified weights for all 14 scenarios are presented in Table A1, while Table A2 provides an illustrative calculation of Spearman's rank correlation coefficient for the C1 +20% scenario.

5.4 Interpreting the spatial concentration of highly suitable areas

The very highly suitable areas were mainly concentrated in parts of Camp Rashid, District 917, which is in the University Sector, and District 927, which is in the Babylon Sector. This concentration is attributed to the alignment of various amenities to these locations, such as the presence of developable land, the relatively low land value or population density, and the potential to be connected to a network of transportation infrastructure or certain natural and historic traits which, when compared to other places, are relatively distant. The outer location of the proposed sites (where the traditional demand-to-congestion ratio estimates that there are fewer congestion problems) suggests that the model is not capturing the concentration pattern of existing sites but rather has a tendency to trigger growth opportunities in locations that are farther out from the main commercial hub to enable secondary centers or new hubs to develop. This can lead to a shift of activities and population away from the center and lessen the strain on the central areas if it is supported by the availability of services, public transport, and links with existing urban fabric. The inclusion of parts of Camp Rashid in the high suitability categories requires careful interpretation. The result reflects the spatial characteristics introduced by the model and does not imply that the land is legally or practically available for development. While the availability of undeveloped land may have contributed to the higher ranking of some sites, military or security status, land ownership, potential for change of use, possible prior contamination, and the capacity of networks and services are subsequent validation factors that must be examined before moving from spatial suitability to development viability. Therefore, these sites should be treated as opportunities for strategic screening only, not as sites approved for construction. The same applies to neighborhoods 917 and 927; a high spatial analysis suitability is not necessarily an indication of the type of development, building height, or density. Detailed plot-level analysis is suggested for sites in these communities that will consider road width, size of plot, building ratios, setbacks, shading and wind conditions, service capacity, and existing residential uses. These results suggest that instead of random placement of high-rise towers in Karrada, development should be in an area where infrastructure, communities, public spaces, services, and transportation are part of the development. By doing so, it helps to reduce some of the negative impacts associated with the development of high-rise buildings in low-rise residential neighborhoods if these issues are not addressed—specifically elevation, density, and visual and social privacy transitions.

5.5 Study limitations and site-level verification requirements

The study results should be interpreted in light of the model's scope and the level of data used. The framework was designed to identify relative variances in suitability across the study area, not to provide a definitive engineering or regulatory assessment for each plot. Therefore, the seven criteria used do not cover all the determinants required for actual high-rise project approval. Requirements to be examined at a later stage include soil geotechnical properties, groundwater depth, flood risk, flight height restrictions, water, sewage, and energy network capacities, traffic capacity and availability of public transport, fire and emergency vehicle access, plot geometry and ownership, land use regulations, building ratios, floor area factor, and the effects of wind, shading, and privacy on buildings and surrounding areas. The categories that are derived, thus, are priorities for further study and detailed evaluation, and not actual permits for development.

5.6 Interpretation of the independent expert validation

Plausible planning of the model outputs is supported by the independent expert validation with an overall mean score of 4.28 out of 5. This shows that the spatial distribution of the suitability classes and identification of priority areas were in general consistent with the professional assessment of the five independent experts. The following agreement should be viewed in the context of an agreement for the use of the model as a strategic spatial-screening tool, however, and not as proof of the legal, engineering, or construction feasibility of individual plots.

The means for the highest-rated validation items, V3 (4.80) and V4 (4.40), were in the very high category, suggesting that there was high expert consensus for the plausibility of the items identified as parts of Rashid Camp and neighborhoods 917 and 927, respectively, as an initial spatial-screening result in the higher suitability classes. This result is significant as these areas were the main areas of very high suitability in the spatial analysis. However, the expert support for their spatial plausibility does not mean that these areas are necessarily available and/or legally appropriate for development. In particular, the interpretation of Rashid Camp remains subject to land ownership, military and security uses, regulatory restrictions, and other site-level constraints that were not incorporated as exclusionary layers in the current model.

Item V6 received the lowest mean score (3.60), although it remained within the high-agreement category. This relatively lower rating suggests greater expert caution regarding the extent to which natural, historical, and hazard-related spatial conditions are represented within the current strategic screening framework. This finding is consistent with the defined scope of the model, which does not incorporate all environmental, legal, and site-specific constraints as non-compensatory exclusion layers. Therefore, the lower score for V6 should not be interpreted as a rejection of the model outputs, but rather as an indication that environmentally sensitive and hazard-related conditions require additional verification before moving from strategic spatial suitability to site-level development decisions.

Taken together, the validation results provide additional support for the use of the proposed framework as a strategic spatial-screening tool while also reinforcing the need for detailed environmental, legal, infrastructural, and site-specific assessments before any development decision is made.