| dc.description.abstract | A study was conducted to investigate the effects of three different roof insulation treatments, namely, Thatch grass (TH), Envirotuff (EN) and Alucushion (AL) on conductive heat flux exchange (HFE) when compared to that without roof insulation (Control, CT) during summer and winter seasons in south-eastern Botswana. Each treatment was replicated three times. Black globe temperatures and outdoor air velocity were measured hourly during the two seasons. Data measured during two of the hottest and two of the coldest months were averaged hourly to obtain diumal patterns and were used in the calculations of HFEs. Data was analysed using the ANOVA procedure in Statistical Analysis System and the means compared using Turkey’s multiple comparisons procedure. In summer, the daytime average hourly HFE values were significantly (p<0.05) lower in TH (2.2i2.1), EN (2.0i2.0) and AL (1.9±2.1) than 15.9±2.1 W/nr in CT. The HFE values at night were also significantly lower for TH (-1.6±2.7), EN (-1.6±2.7) and AL (-1.4±2.7) than -13.7±2.7 W/m2 in CT. In winter, the HFE were significantly lower in TH (4.9±2.4), EN (4.8±2.4) and AL (4.5±2.4) than 36.8±2.4 W/m2 in CT. Correspondingly, the values at night were also significantly lower in TH (-2.4±2.2), EN (-2.1±2.2) and AL (-1.9±2.2) than ‘15.3±2.2 \V/m2 in CT. During summer, cooling is required for 12 hours per day while in winter, heating is required for 17 hours' per day. Further studies are required on cost-benefit analyses of insulating roofs of broiler houses in Botswana. | en_US |
