Fabric formwork is a building technology that involves the use of structural membranes as the main facing material for concrete moulds, which can be flexible and also deflect under the pressure of liquid concrete. In addition to this, the resulting geometry exhibits natural curvature as well as excellent surface finishing that are generally not associated with concrete structures. However, because of the flexibility of the material, when casting with a complex formwork, the result could be unpredictable which might lead to casting failure. Therefore, in this project, the aim was to discover the parameters that control the varied geometry when casting with fabric formwork. And by controlling these parameters, fabric-formed casting can be parameterised and the result can be precise.