The use of clay as a modelling material is long establishedacross a range of creative disciplines. For the purposeof architectural models, clay has often been used tosculpt three-dimensional ideas quickly and to investigateform – especially organic forms, which may be difficultto model in other materials. Perhaps more than withany other modelling material, the tactility experiencedwhen using clay promotes a direct engagement with itthat encourages further ideas to be explored. Such sketchmodels can be developed to test design ideas simply andeffectively. The most important factor when working withclay is to keep it suitably moist by the regular additionof water to ensure it does not crack or dry out. Once themodel is ready it may be fired in a kiln to consolidate itsform, the practice more familiarly known as ‘ceramics’ or‘pottery’. A similar process is used on a much greater scaleto manufacture bricks and roof tiles for the constructionindustry.

         Further to these materials, plasticine and air-dryingmodelling clay are also used in architectural models.Plasticine (also known as plastic modelling clay), unlikethe previous materials, remains formable and can becontinuously reworked as it does not dry out or harden.This makes it ideal for design-development models, inwhich ideas can be repeatedly tested, documented andthen revised. It is available in a variety of different coloursthat can also be mixed together to provide further andsubtler variations. Air-drying modelling clay, as the namesuggests, has characteristics very similar to clay but doesnot need to be fired in order for it to harden.