BCD 2019

93 C AT H E D R A L COMMU N I C AT I O N S T H E B U I L D I N G CON S E R VAT I ON D I R E C TO R Y 2 0 1 9 MASONRY 3.2 BRICK MATCHING MOSES JENKINS W  HEN BRICKWORK has suffered decay it is often necessary to cut out bricks and replace them. It may be possible to reverse bricks in situ or obtain suitable matches from reclaimed stock, but new bricks for repair work often need to be sourced from manufacturers. This article discusses the various characteristics of bricks which need to be considered when matching new bricks for use in traditional brick buildings. Bricks in the UK exhibit considerable diversity in their characteristics, so it is important for both aesthetic and technical reasons to source new bricks which match those used originally. This requires careful consideration and balancing of a number of factors. As well as size, shape, colour and type of brick, technical requirements will be integral to the long term success of any repair made to a brick wall and include water absorption rates, soluble salt content and frost resistance. Just as considerable time is spent securing the correct petrographic match for stone indents or a proper geological match for a patch repair to a slate roof, so too BRICK TYPE INDICATIVE CHARACTERISTICS Handmade Bricks moulded by hand, often with irregular variegated appearance in terms of colour and often smaller than machine-made bricks Common (also referred to as colliery or composition brick) These bricks vary significantly in both texture and colour, generally being rough to the touch and with variegated colour Glazed Uniform, glossy appearance, manufactured in a wide range of colours Engineering Often of a darker colour and dense appearance Special shaped brick Moulded in a nonstandard shape to fulfil a specific decorative or technical purpose Pressed facing Bricks which have been pressed during mechanised brick production, generally with a uniform texture and colour Rubbing Bricks that are softer and free of inclusions to allow cutting and rubbing in gauged brickwork Extruded (also known as wire cut) Bricks which have been produced by extrusion, often with characteristic drag marks on the face Templeton’s Carpet Factory, Glasgow: if care and time is expended in matching bricks for repair work our brick built heritage can be preserved for future generations. should time and care be taken when sourcing bricks for use in conservation, repair and maintenance. THE PROCESS OF BRICK MATCHING The first stage in the process of matching bricks is to identify the key characteristics of the bricks forming the wall being worked on, as discussed in more detail below. Having done this, the process of finding a suitable match begins. This will involve looking at the output of different brickworks and narrowing the search down to those which produce bricks broadly matching what is being looked