This paper covers the history and epidemiology of wall tie corrosion, and what action to take if it is occurring, particularly in cases where the structural stability of a wall or building is threatened. Since reinstatement is often feasible and in some cases L may cost a fraction of the whole rebuilding cost, some methods are suggested. Together with Information Paper IP13/90, which deals with recognition and inspection of corrosion in more detail, it replaces IP28/79 which is now withdrawn. Specific repair methods and hardware are described in Digest 329. This paper will be of interest to surveyors, architects, engineers, specifiers and manufacturers of fixings
