<p>The use of waste fibres to improve the engineering characteristics of earth blocks as a building material in the construction industry has gained much attention in recent times, especially with the benefit of promoting circular economy principles. Plant and animal fibres are commonly used as reinforcement in earth blocks; however, the aspect ratio of the fibres is not usually determined before use. This study investigates the effect of fibre aspect ratio (FAR) on the strength and water absorption properties of earth blocks stabilised with goat hair fibre (GHF) and lime. The FAR used were 75, 100, 125, 150, 200, and 375 with their corresponding fibre lengths of 7.5, 10, 12.5, 15, 20, and 37.5&#xa0;mm. GHF, laterite soil, lime, and water were used for producing the specimens. A constant 10% lime and 0.5% GHF, and 14% water by the weight of the soil were used for the mix. 50 × 50 × 50&#xa0;mm cube and 50 × 100&#xa0;mm cylinder specimens were prepared and cured at 7, 14, 21, 28, and 56&#xa0;days. The specimens were tested for compressive strength, tensile strength, and water absorption. The results showed that the FAR 125 achieved the highest compressive strength of 4.147 N/mm² at age 56 compared to the control specimen of 3.656 N/mm² which translates into a 12% strength improvement over the control. The FAR 125 had the highest split tensile strength of 0.435 N/mm² compared to the control specimen of 0.378 N/mm², representing 13% strength improvement at curing age 56. Again, it was found that FAR 125 recorded the best water absorption resistance of the earth blocks of 4.03% as against 5.69% for the control, which translates into a 29% absorption reduction over the control. The study concludes that GHF incorporation with various FAR into earth blocks with the addition of 10% lime improved the blocks’ strength and water absorption properties. The study recommends the use of 125 (12.5&#xa0;mm) being the optimum FAR of GHF and 10% lime in the production of earth blocks for better performance.</p>