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Pointing / Dotter / Bed Jointer

- the exposed mortar finishing between bricks or stones in a wall, whose primary function is to provide a bed and to prevent water penetrating into the core of the wall. The mortar used should always be softer than the surrounding material. While there are many different profiles, most pointing can be described flush or recessed. Tuck pointing is a fine line of white mortar inscribed onto wide joints in poor or uneven brickwork to suggest a better quality. Black pointing where the mortar was mixed with ash was popular for a while with victorian architects. As a rule of thumb, when repointing, joints should be carefully raked out to at least two-and-and-a-half times their width. "Pointing" is a strange term to describe the process it involves, and probably derives from the widespread practice of lining out the mortar used with a sharp tool or point. It is important that the mortar used compliments the main material of the wall. In brickwork the mortar can be as high as 20% of the total area while in rubble stonework the percentage could be even higher.

The bricklayer uses a straight edged trowel for pointing. There are two basic sizes, the "dotter" which has a three inch blade and is used on joints, and the "bed jointer" which has a six inch blade and is used on the beds. It is common to use a variety of tools ranging from round metal rods to old bucket handles to achieve different profiles for the face of the mortar used for pointing brickwork.

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