Design and Evaluation of a Lightweight Bamboo Slat Roofing System for Sustainable Construction

Abstract

Bamboo’s renewability, strength-to-weight ratio, and low embodied carbon make it ideal for sustainable construction. However, bamboo-slat assemblies are poorly documented, limiting their use in load-bearing roofs. This study develops a modular lightweight roof using multi-slat Guadua angustifolia Kunth and recycled Tetra Pak tiles. The system includes Type A, B, and C flat trusses connected by steel bolts and plates, fabricated from slats to maximize utilization and enable modular assembly. Buckling was analyzed using updated finite-element models for a single Type A truss and the full roof. Experimental validation included a pilot Type A truss test and a full-scale 1:1 roof test. Results indicate the critical positive buckling mode for the full roof has a multiplier of 2.96, consistent with experimentally observed lateral buckling. The full-scale roof reached 9700 N, failing by lateral buckling of the upper chords, with no cracks, and design-load displacements remained below NSR-10 limits. Residual deformations in the Type A truss were attributed to connection slip, local bearing, and post-buckling effects. Interaction between trusses, purlins, and transverse bracing ensured global stability. Overall, the modular bamboo-slat roof system demonstrates structural viability, efficient load transfer, and material sustainability, supporting lightweight roofs while emphasizing stability under extreme and uplift loading.