Decay timer

Health per grade comes from Rust's own game files (build 25824447). How long each grade takes to decay from full health is not in the game files, so the first estimate uses Facepunch's decay times for vanilla servers (twig 1 h, wood 3 h, stone 5 h, sheet metal 8 h, armored 12 h). Servers can change that, so a second reading measures the real speed. Health drops in steps, not smoothly, and the outermost parts of a base decay first, so inner walls can last longer. Doors and deployables are not covered.