Constraints

• Very high density (1000–1100 kg/m³) — significantly heavier than radiata pine structural timber; increases dead load calculations and requires more robust connection hardware
• Checking and splitting during seasoning — large-section members (100mm+) frequently develop surface and end checks as moisture content drops; design must accommodate or conceal checks in exposed applications
• Limited availability of long lengths in structural grades — clear spans over 4.8 m in F14+ grades require ordering in advance; standard merchant stock typically 2.4–4.2 m
• F-grade variability from visual stress grading — visual assessment per AS 2082 has ±20–25% strength variability compared to machine stress grading (MGP); specify MGP-equivalent where tight tolerances matter
• Significant cost premium over structural softwood — $800–1500/m³ for F17–F27 Spotted Gum versus $400–600/m³ for equivalent MGP15 radiata pine structural
• Pre-boring required for all nail and screw fixings — Janka hardness ~11 kN causes splitting and nail deflection without pilot holes; adds labour time on site
• Differential shrinkage requires careful connection detailing — tangential shrinkage ~9–11% can generate splitting forces at bolted connections if not designed with elongated holes or compressible washers
• Interlocked and wavy grain makes planing and dressing difficult — surfaced finish harder to achieve uniformly; rough-sawn sections more practical for most structural applications