The inner wall of the kiln is 9 cm thick and made from high alumina refractory bricks. Outside that is a 3 to 4 cm thick layer of ceramic fibre blanket, followed by a 10 cm layer which is a mixture of loam, ash and argex (lightweight granulated clay). The outer skin, a few mm thick, is made from coarse hessian plastered with loam. It was added because the 10 cm layer beneath is not durable in damp conditions. At the end of a firing the outer skin can be touched without incurring burns but is too hot to maintain the contact.

The images below are links to enlarged photos.