Refractory heat insulating materials

A method of making a shaped article of refractory heat insulating material which comprises forming a homogeneous wet mixture of inorganic refractory fibrous material and binding agent which may be soluble or dispersible in a suitable liquid medium, forming the mixture to the desired shape, drying the shape in a first drying step, impregnating the so-dried shape with binding agent, and drying the shape in a second drying step, one of the drying steps being a drying step which when applied to a homogeneous wet mixture of said fibre and said binder gives a dry product having mechanical properties which are homogeneous between opposed surfaces of the product and the other being a drying step which, when applied to a homogeneous wet mixture of said fibre and said binder, gives a dried product the mechanical properties of which are not homogeneous between opposed surfaces of the product.