Scotland's Brick and Tile Manufacturing Industry

Previously considered to be an inferior material to stone, brick construction was rarely used in Britain until the close of the middle ages. Gerard Lynch looks at its historical development over the last 600 years.

1485 – 1603 – Tudor Brickwork – The popularity of the material can be traced to the revival of brick-making in eastern England in the late 13th and early 14th centuries. This was a direct result of lack of local stone, an increasing shortage of good timber, and the influence of Europe where brickwork was used extensively.

By the Tudor period, the brick-makers and bricklayers had emerged as separate craftsmen well able to rival the masons. From unsophisticated early work, brick building entered its heyday, rivalling stone in its popularity as a structural material.

Bricks were generally made on site in wood, heather or turf fired clamps by itinerant workers. Not only were standard bricks produced but also many in extravagant and elaborate shapes, epitomised by those that formed the spiral twisted chimney stacks for which the period is renown.

The Tudors further patterned their brickwork by inserting headers of over burnt or vitrified bricks into the walling. These dark surfaces ranging from deep purple to slate in colour, were laid carefully in quarter brick offsets in mainly English bond or English cross-bond, to form a diaper or chequered pattern within the predominantly red brickwork.

Tudor bricks were irregular in size and shape and therefore thick (15-25mm) mortar joints were necessary to even these out. The slow setting mortar was of matured non-hydraulic lime (often containing particles of the fuel used in its production), and coarse sand in a ratio varying from 1:2-1:5, the joints being finished flush from the laying trowel.

With the building of Hampton Court Palace, we have not only the seal of royal approval but a monument to the achievement of brick in this period.

1714 – 1830 – The Georgian Period – The late 17th and early 18th centuries were a high point in the use of brick. Their manufacture was much improved, with blended clay, better moulding and more even firing which lead to greater consistency in shape and size. The colours of bricks changed in popularity from red, purple or grey bricks fashionable in the late 17th century until 1730, when brownish or pinkish-grey stocks replaced the hot colours. These were followed in the mid 18th century by grey stocks, and, by 1800, the production of yellow marl or malm London stocks, which were closer to the stone colour desired for a classical facade.

The brickwork was generally of a very high standard, in mainly Flemish bond although header bond was also popular in the early 18th century.

Pointing was executed to a similar standard. As well as giving more protection to the weaker bedding mortar, fine detailing also helped to minimise the visual impact of the joints so that the classical details could be displayed more clearly. ‘Tuck’ pointing was the ultimate development in this quest.

A more expensive solution was to use ‘gauged’ brickwork popularised by Wren using a facade of fine, colour-matched bricks cut and rubbed to exact units, and laid in thin lime putty joints. However, after 1730 this was considered too expensive and was reserved for window arches, aprons and other ornamentation only.

1830 – 1914 – Victorian Brickwork -This was a period of revivalism in domestic architecture and industrial building. The former is seeking a return to ‘medievalism’ and other exotic building forms as a relief from the unspirituality of the machine age. The latter, for the infrastructure of factories, warehouses, railway bridges and so on, all largely met through the cheap use of bricks.

During this period, a greater number of bricks were made and laid than during all the previous periods. Brick manufacturing methods had improved in all respects including quality accuracy, regularity and in range of colours available. From the mid 18th century onwards the manufacturing process, like many others, was becoming mechanised. This enabled deeper clays to be used for pressing into dense bricks for use on civil engineering works.

With improvements in travel and communications, bricks could be transported over wide areas which removed the traditional local variations.

Improvements in the production of mortar also occurred during the late 18th century through the use of washed and graded aggregates, often with colouring. Also, the development of natural cements including Roman cement and other hydraulic limes, which set quicker and stronger, were vital to the speed of construction that the Industrial Age demanded. Portland Cement appeared in the mid 19th century.

Joints reduced to 0.3 inches (8mm) due to the accuracy of the machine pressed bricks and continued to be finished in various profiles. These were popular from the 17th century although the new ‘weather-struck’ and ‘cut’ style of joint became particularly popular.

A variety of face bonds were now used although, in the main, Flemish bond predominated domestically, whilst English bond was favoured industrially.

In all matters of brickwork, the Victorian desire for enrichment was readily achieved by the use of often garish polychromatic work, and the lavishing of ornamentation by detailing mass produced purpose moulded ‘specials’ or by gauged brickwork.

Source – Gerard Lynch

1869 – Electricscotland.com – The art of kneading common clay into rectangular blocks for building purposes seems to have been known from about the time of the Flood, though it does not appear to have been practised by the Western nations until a comparatively recent period. Pipes of clay were used by the Romans to carry off the sewage of their cities; and vases, lamps, statues, and architectural ornaments were formed of the same material. Like other arts which flourished among the ancients, working in clay became extinct for a time; but its value has been long fully appreciated, and the conversion of clay into bricks, tiles, pipes, and more artistic objects, constitutes an important branch of industry in most countries where the material exists. In England the scarcity of good building stone is compensated for by the existence of vast beds of clay, from which many millions of bricks are made annually Scotland is rich in building stone of the best qualities; but, nevertheless, many bricks are made and used, and we have also an extensive manufacture of articles of fire-clay and terra cotta. In Britain, bricks did not come into use until the fifteenth century, and what are supposed to have been the first buildings of importance in which bricks were employed are still in existence. These are the Lollards’ Tower of Lambeth Palace, built in 1454; and a portion of Hampton Court, built in 1514.

In 1784 an Excise duty of 2s. 6d. a-thousand was imposed upon bricks of all kinds. A subsequent Act of the same reign raised the duty and varied its amount according to certain specified varieties of bricks. The duty on common bricks was in 1835 raised from 5s. to 5s. 10d. a-thousand. Four years afterwards the distinction of size and quality in charging the duty was done away with, and a uniform rate of 5s. 10d. was levied. The tax was at all times regarded as obnoxious and as an obstruction to the improvement of the dwellings of the poorer classes; but notwithstanding repeated representations from the building trades, and the almost unanimous voice of the press against the duty, it was not abolished until 1850. Tiles were also subject to duty from 1784 till 1833. The number of bricks made in Britain in the year 1802 was 714 million; in 1840, it was 1725 million; and in 1850, the year in which the duty was abolished, it was 15631 million. The number of bricks made in Scotland annually was 151 million in 1802; and 471 million in 1840. If the great increase in railway and other works, the rapid enlargement of towns, and other recent causes leading to a more extensive use of bricks be considered, the number now made in Scotland cannot be less than 200 million a year.

There are in Scotland 122 manufactories of brick, tiles, and articles of a similar nature; and in connection with these from 4000 to 5000 persons are employed. The manufactories are widely scattered over the country, the farthest north being at Banff and the farthest south at Dalbeattie; but the greater number are in Lanarkshire and Fifeshire, in which counties valuable beds of fire- clay exist. The most extensive is that of the Garnkirk Fire-Clay Company, situated on the Caledonian Railway line about six miles east from Glasgow. The company was originally formed to work coal, but, finding that extensive seams of fire-clay existed on their property, they took to manufacturing that material, which now almost exclusively engages their attention. The principal seam of clay is seven feet in thickness and lies at an average depth of twenty- eight fathoms. Its quality is considered equal to that of the best Stourbridge clay. The manufactory covers upwards of six acres of ground. The raw material is brought in, and finished goods are sent out by branch railways. 300 men and boys are employed, and 200 tons of clay and about an equal weight of coal are used daily. The clay is of a dark colour, owing to the presence of a small proportion of bituminous matter; but when that is dispelled by the action of fire, only silica and alumina remain, and it is the presence of these substances in certain proportions that decides the value of the clay. As it comes from the pits the clay is entirely devoid of cohesion or plasticity; and in order to bring it into working condition, it has to be ground. very fine, and then mixed with water. Several powerful mills are used for this purpose. They consist of great iron rollers, which travel around a circular trough and pass over the clay.

Bricks are the commonest and simplest articles made. Some ingenious machines have been devised with a view to superseding hand labour in this branch of manufacture, but as yet hand labour has the advantage of greater economy. Indeed, the item of moulding, to which only the machines could be applied, forms a small part of the labour in brick-making. At Garnkirk all the bricks are hand-moulded, which is a very simple process and is executed with wonderful rapidity. An expert moulder, with the necessary assistants to keep him supplied with clay, and to remove the moulds as they are filled, will make from 4000 to 5000 bricks a-day. The moulder works at a table, on one end of which is a supply of clay, the other being left clear for his operations. The bricks are formed in a deal framework, resembling a small box with the top and bottom removed. A boy dips the mould in water and lays it on the table. The moulder, taking up a lump of clay, dashes it into the mould, presses it with his hands, and then removes the superfluous clay by drawing a piece of wood over the mould. His assistant, who has meantime laid down an empty mould, snatches up the full one and deposits the newly formed brick on the floor of the workshop. Thus the work goes on until the floor is covered. An important matter in the manufacture is to take care that at least 25 per cent. of the water contained in the clay is evaporated before the bricks are subjected to burning. In some places, and in the case of common bricks, it is usual to expose them in the open air before firing; but that is a precarious practice in a climate like ours, and the best plan is to dry them undercover by artificial heat. The Garnkirk brick-sheds and the drying-rooms in the other departments are fitted with pipes through which the waste steam of the engines is made to pass, and by the heat which these give off the bricks are brought into firing condition in the course of twenty-four hours. The bricks are fired or burned in kilns, but another mode of firing is sometimes employed in which the bricks are built in ” clamps,” or large square heaps with layers of fuel between. Kiln baking is the best. The kilns are built in ranges of three or four together, the smoke from all of which is drawn off by one chimney. Internally, the kilns are about 12 feet in length, breadth, and height, and the bricks are arranged in them so as to allow the fire to act freely on all. About 20,000 bricks are placed in each kiln, and the baking occupies six days and nights. Flooring tiles are made after much the same fashion.

The improvement of agriculture, and the consequent increase of draining, has within the past twenty or thirty years led to a great and increasing demand for clay drain-pipes, and many millions of these are produced in Scotland every year for both home use and exportation. They are made of common red clay—a much softer and less durable substance than fire-clay. The pipes are formed by ingeniously constructed machines, which turn them out at a rapid rate.

The Garnkirk Company do not work in common clay and make no agricultural drain pipes, but they have an extensive trade in the manufacture of glazed fire-clay sewage and water-pipes. As already– stated, clay pipes were used by the Romans to carry off the sewage of their towns and villages. The city of Rome had a complete system of sewage. There were main sewers built with bricks, and branch sewers consisting of pipes of wood or clay. With the decline of the Roman Empire draining as well as many other good things went out of use, and modern minds were only awakened to the importance of the matter when thousands of persons were carried off by diseases which could be traced to no other origin than defective drainage. The importance of providing means to carry away filth from centres of population is now generally known and understood, though in some cases the action is tardy. For main sewers, nothing better than brick has been devised, and for branches, nothing better than clay pipes—so that, in the all-important matter of town drainage, we are no further ahead than were the people who occupied the foremost rank of civilisation two thousand years ago; and it is not long since equality could be claimed. The making of sewage-pipes is an important branch of the manufactures in clay. The pipes are formed by pressing the clay through a die. They are made in lengths of three feet, and each piece has a “collar” worked on one end. After being dried in the stoves the pipes are baked in large circular furnaces. In the course of the baking, a quantity of salt is thrown on the pipes, and that combining with the silica of the clay forms a glaze which covers the entire surface. The pipes are made from two to thirty-six inches in diameter. The heaviest articles made are gas retorts and blocks for the furnaces of glasshouses. Some of the latter weigh fifteen cwt.

Works in terra cotta are also among the productions of the Garnkirk Company. Terra cotta is an Italian term signifying baked clay, but it is commonly employed to designate such articles formed of clay as are used in architectural embellishment. It is if properly made, one of the most durable materials that can be used in building. It was so employed by the Egyptians, Greeks, and Romans, and by various European nations in the middle ages. Monumental vases in terra cotta have been recovered in a state of perfect preservation from tombs in which they had been placed upwards of two thousand years before, and examples are not wanting to prove the weather-resisting powers of the material. Sutton House, in Surrey, built about the year 1530, is covered with ornaments in terra cotta, which yet retain the marks of the artist’s modelling tools.

Many buildings erected in Italy between the twelfth and seventeenth centuries bear terra cotta decorations in a perfect state. The lodge in Merrion Square, Dublin, was built in 1786 of granite taken from the Wicklow mountains, and ornaments in terra cotta were provided for it by an English manufacturer. It is a remarkable fact that, while the granite mouldings have yielded to the action of the weather, the terra cottas are as complete as when put up. Among other honours which belong to the name of Josiah Wedgwood is that of having revived the manufacture of terra cotta in England. When he founded his great pottery in Staffordshire, he began to make articles in imitation of the ancient works in terra cotta, and in that branch, he was soon followed by a lady named Coade. The chief materials employed by them were the Dorset and Devonshire clays, with fine sand, flint, and potsherds. Most of the coats of arms and other insignia placed over the shops in London were made of this material. Though they could not deny its advantages of durability and cheapness, builders did not regard terra cotta with a favourable eye, and it made little progress until within the past ten or twelve years. Its employment in the South Kensington Museum buildings, and in the Royal Horticultural Society’s Gardens, gave the public an opportunity of judging of its suitability for decorating modern edifices, and the general opinion has been favourable to ids use. A large quantity of terra cotta has been employed in the construction of the Albert Hall of Science and Art, and in many other important buildings throughout England. In Scotland our beautiful and easily carved freestone does away with the necessity for introducing terra cotta in an architectural fashion except in the form of chimney-pots, for which it is well suited; but statues, vases, and fountains made of it are now much used for the ornamentation of pleasure-grounds and gardens. A recent discussion in the Royal Institute of British Architects shows that considerable difference of opinion prevails as to what are the best materials for making terra cotta. Some eminent men in the architectural world maintain that, in order to endure the severe climate of Britain, terra cotta should be made with a hard vitreous body composed of Cornish clay, ground flint, and Cornish stone, with a glaze added. Others are of opinion that the composition of the Albert Hall and South Kensington terra cottas are the best, and the weight of argument appears to lie on their side. Messrs Alexander Wilson & Son, fire-clay manufacturers, Dunfermline, have made a great part of the terra cotta required at South Kensington, and are now engaged with the columns, capitals, cornices, friezes, and other ornamental parts. They have been providing all the ashlar work required. The clay used is of a very fine quality.

The articles made of terra cotta at Garnkirk are chiefly statues, fountains, vases, brackets, pedestals, and chimney pots. The clay for these is carefully ground. In the firing, and subsequently, a number of articles are broken, and the remains of these are carefully preserved, and, when ground, a certain proportion of the produce is added to the fresh clay. The object of this is to reduce the “shrinkage,” or tendency to contract, which the pure clay possesses. The articles are formed either by modelling or casting in moulds of plaster of Paris. Most of the statues and vases are after classical patterns.

Only a small proportion of skilled workmen are required in brick and tile works, and the great body of the men rank as ordinary labourers. They are chiefly Irishmen, and their earnings may be stated at from 15s. to 17s. a-week. Some of the skilled workmen earn as high as 30s a week. The fire-clay is excavated by men who have been bred as coal miners.

13/09/1933 – Falkirk Herald – Research departments report on economic aspects – The brick-making art is so old, and people are so used to brick buildings in England, that it is somewhat surprising to realise that brick was a luxury building material until London was largely rebuilt of brick after the Great Fire in 1666, which thus gave a tremendous impetus to brick-making. This is one of the many interesting facts contained in a report on the economic and manufacturing aspects of the brick-making industries, issued by the Department of Scientific and Industrial Research.

Since the 18th-century brick has been the staple building material in England. Much attention was given after the Great War to alternative materials for small houses, such as concrete poured or cast), steel, cast iron, timber, half-timber and concrete, sand-lime bricks, rammed earth, hard chalk or chalk blocks, but no method of construction tried has proved cheaper than the normal ones based on the use of brick.