Figure 7 : Thermal comfort condition for stabilised soil block walls with iron sheet ( top ) and thatched roofs ( bottom ).
Conclusion
This paper evaluated the effects of various construction methods on thermal comfort in low-income tropical housing in Uganda . Dynamic thermal simulations were conducted in EnergyPlus and the risk of thermal discomfort in naturally ventilated buildings was assessed for different walling and roofing methods . According to the results , an average internal operative temperature of 26 ° C would be an ideal comfort temperature in free-running buildings in Kampala . The maximum average internal temperature was also defined as 29 ° C . The comfort and maximum temperatures could however vary by up to 1.8 ° C depending on the running mean outdoor temperature .
According to the results of the simulations , roofing method / material is the most critical factor affecting thermal comfort conditions in low-rise free-running buildings in tropical climate of Kampala . The results reveal that , compared to iron sheet roof , thatched roof improved thermal comfort conditions by up to 15 times for criterion 1 of CIBSE TM52 guidelines . In other words , the risk of overheating ( frequency of thermal discomfort ), was reduced by up to 15 times when iron sheet roof was replaced with thatched roof . The two other criteria defined by CIBSE TM52 were also improved considerably for the thatched roof construction . Therefore , it could be argued that , when it comes to construction materials , improving thermal performance of the roof is key to improving thermal comfort in naturally ventilated buildings in tropical climates . Although important , walling materials were found to be less critical compared to roofing methods . The results of this study revealed that the thermal performance of different walling materials , with the exception of hollow concrete blocks , were almost identical . Hollow concrete block walls performed the worst in terms of providing thermal comfort . This was despite the fact that the thermal conductivity of hollow concrete blocks was considerably lower than solid concrete blocks , bricks and stabilised soil blocks . A possible reason for this is the much less thermal mass of hollow concrete blocks compared to the rest of the walling materials .
Improving thermal comfort in low-income tropical housing : the case of Uganda 621