Joists are laid level to receive flooring (notched or packed as allowed), spaced to suit the flooring, sprung appropriately; joints only over supports with at least 30 mm bearing each (butted or scarfed, not lapped, where in line); paired joists under walls parallel to joists for fitted floors and joists under loadbearing walls for platform floors; deep joists (depth at least four times breadth) restrained at supports by trimmers or blocking and, for long unseasoned spans without a ceiling below, rows of strutting; rim boards adequate for loads; and joists fixed at every support, fully seated in any hanger. Amendment 1 revised part of this clause (4.2.2.3); the new wording is not held.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.