The present investigation aims to perform experimental study to show the feasibility of application composite materials as secondary roofs, as well as their capability for reducing cooling load in building. Moreover, compare some of their mechanical properties and acoustic insulation with conventional secondary roofs. Three basic models, which are common, were chosen for the construction of buildings' roofs in Baghdad (concrete and concrete tiles as basic components of the first model, brick and clay tiles as basic components of the second model and brick and normal tiles as basic components of the third model). In addition, three composite materials were used in present work (fiber glass+ Nylon 66, fiber glass+ one layer of date palm cortex and fiber glass+ two layers of date palm cortex). The gypsum plates have been selected as a conventional secondary roofs when performing calculations and comparison. The results show that using proposed composite materials leads to significant reduction in cooling load by about 69.56 %, 65.3 % and 65.5 % respectively for the three models. In addition, the comparison of acoustic insulation shows that the proposed materials offer good acoustic insulation. Moreover, these materials able to afford external shocks better.