These were deter- mined by weighing the cement mortar cube samples and then drying them at gauge dry weight(D) before king them in water for 12 h to measure their suspended weight(s) Finally, they were wiped with a cloth to absorb water droplets and then measured again for their saturated weight(w) The final results for the different cement mortars were derived from the aver age of 3 separate samples. They were then soaked in water for 28 days and then tested for their compressive strength. In accordance with JIS R 2618 standards, they were also tested using the TCA(Thermal Constant Analysis) technique to assess the thermal conductivity of each e when mixed with varying proportions(5-15r) of coconut coir fiber and oil palm residue to calculare their thermal conductivity coeffidents for comparison. 3 Natural fiber cement flat sheets In accordance with ASTM c1185 and ASTM c1186 standards l the ex ments for determining the mechanical properties of the different cellulose fiber ement flat sheers were conducted on 30 x 15 x 0.5 cm spedmen to obtain the products that are suitable to use. Both types of cellulose fibers were tested using ratios of 53 and 10x by weight of Portland cement to determine their flexural strengths