Abstract
The study investigated the conversion of waste wood particles (sawdust) and cement into ceiling boards. The boards were produced using two different chemical additives - Calcium oxide (CaO) and Calcium chloride (CaCl ) at six different levels of concentration 0%, 1%, 2%, 3%, 4% and 5%. The stock were thoroughly mixed and spread in a frame. The mixture was transferred to a hydraulic press with plate and pressed to required thickness - 6mm at 1.2N/mm2 for 24 hours and left to dry in an open room for 7 days to ensure proper curing. Modulus of rupture (MOR), Water absorption (W.A%) and Thickness swelling (T.S%) were determined. Analysis of variance (ANOVA) was carried out to determine the level of significance at 5% while Duncan multiple range test was used for the follow up analysis. The results show that MOR ranges from 20.4N/mm2 to 53.89N/mm2 and 20.37N/mm2 to 50.34N/mm2 for CaO and CaCl additives respectively. Analysis of variance revealed that additives and their concentration levels have significant effect on modulus of rupture (MOR), water absorption (W.A), and thickness swelling. It was observed that calcium oxide (CaO) produced a better board in terms of MOR (53.89N/mm2), W.A (43.4%) and T.S (27.03%). It is hereby recommended that CaO at 5% level of concentration should be used in the production of cement bonded particle board for better performance..

Key words: Cement Bonded Particle Board, Sawdust, Additives, Modulus of Rupture, Swelling