The hand -made process begins with the digging and weathering of clay over a period of at least 12 months.
The clay batt is placed into a mould, pummelled by hand, and with the excess clay wired off, a punch is brought down which forms the nib and also impresses from the strike plate, the company name and the maker’s identification mark. Two nail holes and a manufacturing identification code are also struck.
A master tile maker can produce 2,000 standard size tiles each day, with under half that number if making special tiles such as ‘unders’ and ‘overs’, which require the clay being cut to shape and formed over a wooden mould. The tiles are stored on individual trays for at least 24 hours in a warm room to remove excess moisture and then put into a drying chamber where the moisture is gently removed. During this process, the tile shrinks by 7%.
The dried tiles are again checked for quality before being placed onto a kiln car which is moved into a pre-kiln dryer to remove any final moisture. The tiles are then sent into the kiln where the final firing process takes place.
The temperature in the kiln is raised to in excess of 1,000 degrees centigrade during this process; the tile also shrinks by a further 6%. When cool enough to be handled, each individual tile is checked for quality before being placed into a crate to be stored prior to distribution to the customer.
Although most concrete tiles are machine- made, some manufacturers produce hand- made fittings to complement main roof tiles. These can include items such as purpose- made hip and valley tiles, which are custom made to suit the pitch and angles of the roof.
These hand-made concrete tiles are formed starting with a flat section of semi-dry concrete mix which is placed on to a jig or mould and shaped to the correct angle and dimensions to suit the design requirements of the roof fitting. The hand made tiles are then placed in a curing chamber to cure before storage and distribution to the customer.