**6. Results**

#### *6.1. Material Intensity Typologies, Height Assumption, and Residential MITs*

Table 1 shows the material intensities of the six different material intensity typologies (MITs) examined in this study, which reflect A&B's local construction styles verified through on-site empirical evaluation observations. The table summarizes the different building use type classes that are categorized under each material typology class.


**Table 1.** Material intensity typologies (MITs) for Antigua and Barbuda (kg/m2) based on local construction styles. All numbers are rounded to one significant digit.






#### *6.2. Material Stock (MS) of Buildings*

In 2004, the total material stock for buildings in A&B was calculated at 4.7 million tonnes (mt), which is equivalent to 58.5 <sup>t</sup>/cap. Concrete accounts for more than half the total MS in buildings, at 62%. Aggregates consume the second-largest amount of materials at 25%, followed by steel and timber with 9% and 4%, respectively.

In terms of the building use type classes, Figure 2 shows that the residential building class dominated with 53% of the total material stock, accounting for 2.5 mt. Tourism and commercial buildings represented the next largest class, accounting for approximately 18% and 17% of the total material stocks, respectively.

Figure 3 shows the density (represented by the standard deviation) of the total material stocks by dividing the island into 100 m<sup>2</sup> cells. The densest cells of material stocks are represented by blue and red, while the gray cells correspond to the low accumulation of material stocks.

The hotspots of building material stocks are located mainly around the coastal areas in high developmental areas and main tourism districts. There are a few dense cells located inland on the northern side of the island which are mostly associated with commercial and transport services.

St. John's city is the main commercial district and the primary port of entry for both the trading of goods and cruise ship arrivals in A&B. The area demonstrated the highest accumulation of building material stocks concentrated within the city core. Other areas, such as Jolly Harbour and English Harbour, indicated high amounts of material stocks and are considered to be intensive tourism areas. The two locations are major tourist hubs with surrounding small-scale and large-scale hotels and restaurants located around the areas' perimeter.

**Figure 2.** The percentage share of material stock illustrated by the building use type categories in Antigua and Barbuda for 2004.

**Figure 3.** A standard deviation map of the spatial distribution of the total material stock (MS) of construction materials within buildings in Antigua and Barbuda (2004).

#### *6.3. Sea Level Rise (SLR) Scenario*

The vulnerability of the building material stocks in A&B was assessed in terms of a SLR analysis. This analysis identified the number of buildings, material stock, and the respective building use type categories that are exposed under a 1 m and 2 m sea level rise scenario based on global predictions for 2100 [64]. Tourism was the most impacted building use type under the 2 m sea level rise projections, as shown in Table 2 and Figure 4. The tourism industry accounted for approximately 81% of the total material stock exposed in A&B under a 2 m SLR scenario. This is equivalent to approximately 19% of the tourism industry's material stock exposed and 16% of the country's GDP.

**Table 2.** The percentage of exposed material stock within the affected building use type categories identified in the sea level rise analysis and flood risk assessment.


**Figure 4.** Four impacted areas on the island that would be exposed under a 2 m sea level rise scenario including Marina and Dickenson Bay, St. James's Club, Jolly Harbour, and Long Bay. Exposed areas are highlighted in orange.

The majority of the tourism facilities in A&B are situated on the coast and are directly exposed to the threat of SLR. Residential buildings located near the coast are also threatened and consist of 15% of the exposed buildings. In Table 2, tourism, historical sites, and transport-based buildings were most vulnerable as they accounted for the largest proportion of buildings exposed, assessed at 18.8%, 14.5%, and 14.3%, respectively.
