A factorial experimental design method involving 24 runs was employed for production of briquettes. The variables investigated in this study were chosen based on their expected influence on briquette quality: sample batch (S), i.e., two different samples, A and B, of rice husks and corn cobs obtained for two different seasons and farms sites, material ratio (M), i.e., percentage mass of rice husks in the blend of rice husks and corn cobs, and binder addition (B), i.e. mass of starch and water added as a percentage of the rice husk and corn cob blends, and compaction pressure (P). The response variables measured were green (immediately after extrusion from the mold) and relaxed (after 24 hours curing) unit densities, unconfined compressive strength, mass lost in abrasion and shattering tests (i.e., “durability rating”) [57], and water absorption. The methods used to measure these response variables are summarised in Table 2. Unless otherwise specified, each test was repeated for three briquettes.