TECTUM Roof Deck TECTUM I Excellent sound absorption available in plank, long span plank, and tile. TECTUM III & IIIP Acoustics, insulation, and nailable surface in one panel. TECTUM IIIP edge detail is specifically designed for high humidity applications. TECTUM E & E-N Composite panels made with EPS insulation or GPS insulation that exceed ASTM C-578 Type 1 requirements and bears the UL classification mark. TECTUM V Recognized for use in Type I and II construction where fire-retardent-treated wood is allowed in accordance with IBC Section 603.1 (91).