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Handmade Tiles

Clay can be excavated, moulded and burned without any expensive or elaborate machinery and for centuries clay roofing tiles have been used. There are two qualities of tile:
Hand made tiles are moulded from a sandy clay which is pressed into shape by hand pressure so that even if some form of screw press is used the clay will not be heavily compacted. During burning the tiles shrink and there are quite noticeable variations which give a tiled roof attractive appearance. The tiles vary in colour from light brick red to almost black and many of the more expensive tiles are sand faced produce the rough texture which is popular.
    Handmade tiles fairly readily absorb water and should not be laid at a pitch of less than 45°to horizontal. If laid at a less pitch these tiles may become saturated in winter and frost will then cause them to disintegrate.
     Machine pressed tiles are made from selected pure clays which are thoroughly ground to a fine condition. The clay is mixed with very little water and is heavily machine pressed into tiles. Because little water is used to make the clay sufficient plastic for moulding the tiles do not shrink noticeable during burning and because the tiles are machine moulded they have smooth faces. The tiles are very hard and dense and do not absorb water readily and can be laid on a roof with a lower pitch than can the hand maid tiles. Machine pressed tiles have successfully been laid at a pitch of as little as 30° to the horizontal but the minimum pitch for these tiles is generally accepted as being 35° to the horizontal. Because of their uniformity of shape, texture and colour, machine pressed tiles do not make for so attractive a roof as the hand made variety. 
Some machine pressed tiles are faced with sand before being burned to give them a more attractive appearance. If clay roofing tiles have been made from clay which is free from lime and stones and the tiles have been hard burned and the tiles are laid at a suitable slope they will have a useful life of up to a hundred years or more. Good quality clay tiles weather well, which means they are resistant to damage by rain, frost, heat and all the dilute acids in industrial atmospheres. 
   Over the course of years the colour of clay tiles becomes somewhat darker and it is generally accepted that the appearance of a tile roof improves with age. Good quality clay roofing tiles have a useful life of many years, require no maintenance and are highly resistant to damage by fire. The original cost of a roof covered with clay tiles is moderate and from the point of view of durability and appearance clay tiles are one of the most satisfactory roof coverings in use today. 

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