<![CDATA[The installation stage (module A5) of building-material life cycles is poorly represented in life cycle assessment (LCA) databases, particularly for developing-country practice. This study reports a partial, installation-related life cycle inventory (LCI) with screening-level greenhouse-gas (GHG) characterization not a full cradle-to-grave LCA for ceramic floor tiling, and documents the installation waste generated under one observed layout. Following the four-phase procedure of ISO 14040/14044 and the modular framework of EN 15804, a functional unit of 1 m² of installed floor was defined. The study quantifies only selected foreground flows: tile delivery transport (A4), cutting energy and offcut generation as selected A5 activities, and offcut-transport (C2); upstream manufacturing (A1–A3), most other A5 inputs (adhesive, mortar, grout, water, packaging, cleaning, equipment), end-of-life treatment (C3–C4), and the use stage were not quantified. Detailed measurements were obtained from one regular, unobstructed 48 m² reference room installed with a center-referenced, straight-lay pattern within a hospital project in Central Java. A waste factor of 2.33% (unrecovered offcut area over installed area) was observed in this room; total offcut generation was 3.33% and internal reuse recovered a further 1.00%. No alternative layout, corner-referenced start points, or optimization scenario was evaluated, so the value is reported as a case-specific observation rather than evidence that the layout prevented waste. Within the selected and counted flows, and excluding A1–A3, delivery transport (A4) contributed approximately 98% of the calculated GHG under a loaded one-way assumption; including an allocated empty return raised the counted total by about 98% and the A4 share to roughly 99%. A sensitivity analysis across freight and grid emission factors, return-trip treatment, transport distance, load factor, waste baseline (5/8/10%), and reuse substitution (0/50/100%) confirmed that conclusions are contingent on the narrow boundary and adopted factors. The study's contribution is a documented primary-data case inventory for selected ceramic-tile installation activities in Indonesia, not a validated waste-prevention model.]]>
