Agriculture Reference
In-Depth Information
standard published by the British Standards Institution (BSI). This replaced
BS 3921:1985
Specification for Clay Bricks
, which was withdrawn in 2006.
Only a handful of traditional brickmakers continue providing rubbing bricks
for gauged work, which affects the variety of rubbers now available. This is
especially so for the repair and restoration of cut, rubbed, and gauged work
on historic buildings. This contraction in manufacture has been mirrored by
a steep increase in cost to levels that are of concern to all involved with trad-
itional brickwork and its conservation.
Whilst rubbing bricks always commanded higher prices than standard bricks
(typically 50-150% more), the current cost differential is several times greater,
which has a clear effect on project costs. Colleges wishing to include gauged
work as part of their curricula, cannot on the limited funds available, afford
such expensive bricks, leading to a reduction in training opportunities and a
long-term contraction of the skills necessary for the repair and restoration of
historic brick buildings.
Though utilising quality top clays capable of making rubbers, no current
traditional brickyard exploits the naturally high silica-bearing brickearths that
were the raw material for the best rubbing bricks. Furthermore modern brick-
yards no longer fire their bricks using slower-burning and lower-temperature
wood as a fuel, preferring labour-saving coal and liquid petroleum gas that
burn quickly and rapidly reach temperatures well in excess of 1,000ºC.
The significance of using such clays and high firing temperatures in excess
of 1,000ºC on the quality, workability, and durability of modern rubbing bricks
formed part of this research programme. The open-pore structure of modern
rubbers, like historic rubbers, is of significance in relation to the positive dur-
ability of the brick.
Currently, however, three traditional brick companies produce a selection
of rubbers with varying degrees of associated services for cut, rubbed, and
gauged work. These are W.T. Lamb and Sons (Bricks and Arches) Limited in
Sussex; Bulmer Brick and Tile Company Limited in Suffolk and W.C. Reades
of Aldeburgh in Suffolk. Michelmersh Brick and Tile Company Limited in
Hampshire and H.G. Matthews and Sons of Buckinghamshire are working
towards the production of a rubbing brick from their respective orange/red,
red and Chalfont Red range of hand-made bricks. Also several other brickmak-
ers like W.H. Collier Limited in Essex, The York Handmade Brick Company
Limited, Yorkshire and Hanson Building Products, Bedfordshire, are seeking
to develop and produce rubbing bricks.
W.T. Lamb and Sons Limited
W.T. Lamb and Sons Limited, which incorporates Lambs Bricks & Arches,
have been producing rubbing bricks for the longest period of time. For their
