**4. Results**

#### *4.1. The Results of the Suggested Scenarios for Enhancing the Community Performance*

#### 4.1.1. Scenario One

The community livability could be improved by providing some daily required services such as shops, supermarket, pharmacy, restaurant and cafe, financial services, assembly and leisure, hot food and takeaway. This could be obtained by converting a number of the residential units in the community to provide the missing services. In addition, to add two stories for these units to increase building design diversity (one of LEED's requirement for sustainability) and height diversity as well.

Land use has been improved and a number of facilities were increased by converting some units into services for the daily important and missing facilities, such as adding supermarket, laundry and a pharmacy to be within 300 m–500 m for more than 50% of the community units to fulfill the LEED's land use diversity requirement.

#### 4.1.2. Scenario Two

The second opportunity is enhancing the community services as well as the accessibility, by opening new access to the neighbor community, Layan community, as both of these communities are developed by the same developer (DPG). The new access will allow the residents to benefit from some services that are already existed in Layan community, such as supermarket, bookshop, and small cafe. Furthermore, opening new access to Al Quadra Road will enhance the accessibility and the movement entirely (Figure 6).

Opening new access to Layan community (Scenario Two) would improve the community livability, even though some services are still indicating a weak performance such as educational and medical services. This could be resolved by providing these services

(primary school or medical center) in Layan community, as it is larger in area and has a number (7) of mid-rise buildings, which could be useful for this type of services (Table 1).

**Figure 6.** (**a**) The existing gated community—one access; (**b**) New access to the neighbor community enhancing access.

Both scenarios 1 and 2 indicated improvement toward a more sustainable setting, as most of the mentioned services are within the LEED ND requirements (i.e., 200–300 m) (Table 1), even though the other services are still at a distance of 12–15 km from the two communities and therefore not able to fulfill the LEED ND sustainability credit requirements.

## 4.1.3. Scenario Three

Enhancing livability could also be achieved by increasing the open spaces and green areas; the open spaces are limited in the community but could be increased when adopting the new access to the Layan community. On the other hand, the green area could be increased by planting the uncultivated areas, which are calculated using site surveys and Google Earth (Pro) [44], while represented in CityCAD by 35% of the landscape area (Figure 7).

**Figure 7.** (**a**) The existing community walkway beside a road, (**b**) The pedestrian walkway that could be enhanced by adding rubber track, shading devices, and sport equipment.

In addition to increasing the number of trees and adding a green belt alongside the community boundary wall, adding some sports and kids playing equipment to provide the residents and the kids with a place for relaxation and amenity could allow for social communication, while also improving social sustainability (Figure 8).

**Figure 8.** Options of shading devices for walkways [45].

Furthermore, walkability could be increased by providing a rubber pathway, shaded walkway [45,46], and a number of benches to encourage people, especially elderly people, to walk and use the community green areas, as encouraging elderly people to walk is one of the social sustainability targets [47,48] (Figure 9).

**Figure 9.** Adding benches and enhancing empty areas by using hard and soft landscaping [45,46], and improving walkability for pedestrians by adding rubber walkways (1.1 m width) and outdoor equipment according to the LEED ND requirements

Moreover, adding a green belt around the community could provide more protection and shade areas further to increasing the total number of trees, which has an important role in enhancing the community environmental performance (Figure 10).

**Figure 10.** Planting the community boundary wall [42]. (**a**) Current Setting; (**b**) After Improvements.

#### *4.2. The Effects of the Adopted Scenarios on Solar Shading and Solar Gains*

Running IES-VE simulations with different heights of community units showed the importance of the height diversity in creating preferable shaded areas for walking people, in addition to the effect of reducing solar gains from the surrounding units. Figure 11 shows that the solar gains of the surrounding units decreased from 100% to 80% (80 h) when applying height diversity.

**Figure 11.** (**a**) Solar gains and the effect of diversity in building heights on shading parameters; (**b**) Solar gains and the effect of planting the boundary wall.

The effect of diversity in building heights for creating comfortable outdoor environments was proven by Edward (2010). The researcher explored the benefits of the diversity, dense, and compact form on the outdoor environment, presenting the "Environmental Diversity Map" to show the effect of diversity on the three microclimate parameters; temperature, shading and wind on the outdoor environment [23].

A model using IES-VE SunCast analysis to study the effect of planting height and dense trees along the boundary wall were simulated, as shown in Figure 11b. It is clear that the boundary units adjacent to the boundary wall are varied in solar gains, and the exposure percentage between 50–70% depending on the height and the dense of the trees, with 100% solar gains for the other units.

The effect of the first scenario and the modification in building height diversity analyzed and explored using one of the community units, Unit No. 91. Unit 91 was selected for this analysis due to being oriented toward west direction and has maximum solar gains with 100% in the existing case, and is close to the chosen building, to be converted to serve for the missing services, which is modified and increased in height by adding two more stories (to Unit No. 90), and the adjacent Unit 91 could be therefore less in solar exposure by 20% as it has only 80 h of exposure to the sun (Figure 12).

**Figure 12.** Building height diversity and shaded roofs adjacent to the modified building, Unit 91. Less in solar exposure by 20% and 80 h during the month of June. (**a**) SunCast solar shading analysis in percentage; (**b**) SunCast solar shading analysis in hours.

Moreover, using ApacheSim application within the IES-VE software showed that there is a reduction in solar gains by 20% for the modified case compared to the existing case (Unit 91), and the solar exposure and solar gain hours are 80 h less in total during the month of June, with a reduction from 420 h to 340 h. Furthermore, the reduction in solar gains for Unit 91 showed a comparison between the existing case study (Unit 91) and the new shaded same unit with a reduction of 18.5% in total solar gains on 1 June.

#### *4.3. The Community Assessment Using LEED (ND) Rating Tool*

LEED Neighborhood as a sustainability assessment tool was used to evaluate the community sustainability or greenness, where the tool rating system consists of five categories, and each category covers a number of requirements. The requirements divided into mandatory requirements and optional requirements; for optional requirements, LEED allocates a number of points or credits for each category, as shown in Table 2.

#### **Table 2.** LEED (ND) allocated points.


The total number of points collected indicates the level of each community sustainability according to the following scale: Certified 40–49, Silver 50–59, Gold 60–69, Platinum 80+.

Using the LEED Neighborhood and Developments checklist to assess Al Waha community through each of the five categories resulted in the following:


In total, the community collected only 32 points. This result indicates a low level of sustainability, and the community could not be certified as a green or sustainable community according to the LEED (ND) assessment tool. Generally, the weaknesses are indicated in land use, facilities, accessibility, transportation system, and water and energy efficiency.

The modified case study according to the three scenarios was assessed using the LEED assessment tool, and the results for each category are as follows (Figure 13):

• Smart Location and Linkage: In addition to the 11 points that were collected from the existing case study assessment, providing new access to the community to the main road and new access to the Layan community, adding four additional points, to be 15 points in total for this category.


**Figure 13.** LEED assessment, comparison between existing and modified case study.

Moreover, it is worth mentioning that the aspect of building density has helped to improve and optimize relations among the factors in urban geometry [4,6], and therefore emphasizing on this aspect as a key solution in this analyzed context, which should also be taken into account in different climatic zones.

In total, the community collected 46 points and could be certified as a green community (Appendix A). This result shows the effect of the applicable practices and modifications to enhance the community sustainability.
