Generally 100-250mm. See designers guide (page 8) available in the downloads section.
All Cirtex Gabions are galvanised. PVC Gabions have an extra plastic coating. PVC Gabions have a design life of up to 120 years.
Galfan is a type of galvanising coating that has a small percentage of aluminium added and is considered to perform better than standard galvanising. Cirtex recommends that where extended life is required, the PVC option is chosen as this offers optimum performance over just a galfan coating.