Apply at least 2 coats. Fire on and apply a third.
Are you tired of glazes running and pots getting stuck to your kiln shelves? Kiln shelves are expensive and a pain to have to replace, so when a pot gets stuck to the shelf because of a runny glaze, it could be quite frustrating. Using kiln wash on shelves helps to prevent such problems, as it lengthens the life of the shelves, and accidental glaze drippings are easily removed without damage.
Kiln Wash is a dry, premade powder that can easily be mixed with water just prior to use. Simply dissolve the powdered kiln wash in a small bucket with water until it is a milky consistency (similar to a thin glaze). Then use a wide brush to apply a thin coat onto the shelf (shelves should be clean prior to kiln wash application). Let the kiln wash dry and apply additional coats until the thickness is about 1/16". Let each layer dry in between coats. If kiln wash is applied too thickly, it will flake off and chip more readily. During the first application, we recommend applying 2 coats, firing the shelf and then applying a third.