# High-Rise Social Housing in Hot-Humid Climates: Towards an 'Airhouse' Standard for Comfort
## 2 Materials and Methods  
This research started by exploring the natural ventilation strategies present in vernacular Malaysian architecture, comparing it with modern social housing [4]. Here, we propose the introduction of a new design standard for high-rise social housing, named the 'airhouse' standard. Two traditional houses (TMH) were analysed and compared with PPR first-generation housing units located at levels 1 and 10. Two common areas, the living room and kitchen area, were selected. The air temperature and humidity in both buildings was similar, but the air movement was dramatically different: 1450.3 L/s (1.45 m/s) in the vernacular house and 31.7 L/s (0.03 m/s) in the modern building. The standard focuses on passive measures, which could be incorporated within the building fabric. The size and location of opening areas are two key factors that can allow air to enter the building and to enhance its movement. The 'airhouse' standard proposes that the percentage of openings in the building facade should be more than 15%, depending on the height of the residential units, increasing or decreasing the area depending on the height of the residential unit. In order to enhance air movement and cross ventilation, a full-height opening configuration with three elements (main window, fixed louvres, and adjustable louvres) is also proposed. Fixed louvres are introduced at the upper level of the internal walls to allow air to circulate throughout the units at all times time. The proposed standard also suggests that the depth of rooms should be decreased to enhance cross ventilation and that overhangs should be provided to protect all windows from solar radiation. This initial research has proven that an appropriate envelope and plan layout configuration could assist in successfully increasing the indoor air movement rate and significantly reduce energy consumption, as well as carbon emissions. Based on all the results defined in the research, the initial design considerations of the 'airhouse' standard were established (Table 1, Figure 4). \begin{table}
\begin{tabular}{c c} \hline
**Recommended Parameters** & **Airhouse Conditions** \\ \hline Air Temperature & 25–27 \({}^{\circ}\)C \\ Relative Humidity (RH) & 30–60\% RH \\ Air Movement & 0.30–1.5 m/s \\ Energy Consumption & \textless{}5000 kWh/year \\ Carbon Emissions & \textless{}2500 kgCO\textgreater{}year \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Design conditions of the ‘airhouse’ standard (2012) for naturally ventilated buildings. After a preliminary study of ten high-rise social housing developments across Kuala Lumpur, the research continued by gathering in-situ data to evaluate the actual comfort and health conditions in the existing, recently built, high-rise social housing buildings in Kuala Lumpur in detail. Two cases were considered, namely, the PPR Beringin, first occupied in 2004, consisting of six blocks of 18 and 15 storey height, with 1896 units in total (316 units per block). The design of each block includes two large open atriums in each block to provide natural lighting and ventilation into inward rooms, and a row of residential units abutting to a corridor (Figure 5). The windows are single-glazed glass louvres. Three units in block C were selected, located at level 1, level 10 and level 17, representing lower, intermediate, and upper parts of the block, and different conditions of obstructions (Figure 6). The PPR Seri Aman, from the second generation of the PPR, was completed in March 2017 and currently accommodates approximately 1560 units in 4 blocks of 20 and 19 storey height. This  
Figure 4: The unit plan layouts for the People’s Housing Programme (PPR) first-generation units (**left**) and the new proposal for the ‘airhouse’ standard (**right**) [4]. Figure 5: Typical floor plan of the PPR Beringin (First Generation). Figure 6: Site section of the PPR Beringin. second-generation consists of two rows of residential units abutting to a corridor, with an enclosure setting environment compared to the previous design.