Fig. 4

Typical examples of structural features of houses from cluster 2, typically of contemporary design with better a priori ventilation planning, and usually built with brick walls and iron sheet roofs, representative of various stages of completion. A, B Illustrate how a house may be built in two halves, with the second being an annex to the first, necessitating construction of a small upper wall between the overlapping roofs where additional openings for ventilation and lighting may be built into the structure (A). C, D Illustrate typical examples of temporary brickwork structures used to fill in deliberately constructed window gaps, usually for several years while the household saves enough money to install window frames and security bars (E, F). Note that the house depicted in D was the one identified by the cluster analysis as the medoid of the second cluster of houses with well-planned ventilation features, meaning it was the most statistical representative member of that cluster of houses