Building F3 of Fengchu Complex at Zhouyuan Site—the largest known freestanding Western Zhou （c.11th century-771BC） structure—contains courtyard stone installations (standing stone and paving stone) crucial for determining its function. Through petrological analysis of construction materials, this study demonstrates distinctive characteristics in the standardized stonework of the pavement features. These distinctions manifest in three dimensions: standardization level, masonry techniques, and dimensional/spatial configuration. Textual evidence corroborates that the pavement served practical functions while embodying the builders’ architectural intentionality. Though its precise nature (ancestral temple, earth altar, or elite residence) remains unresolved, Building F3 represents a culturally hybrid structure integrating Shang and Zhou architectural traditions. This synthesis reflects the multicultural convergence within the Western Zhou royal heartland, particularly at Zhouyuan, during the early dynastic period.