Science has the solution to the housing problem ready for immediate application, but she must be allowed to pursue her progressive way untrammelled. From what one might be able to assume, brick and stone represent the only building materials at our command. But are they? In other fields, where restraining forces are not allowed to secure the upper hand, huge forward strides are being made and with a material we, as a supposed commercial nation, have scarcely noticed.
I refer to concrete. We have only to turn to the engineering world to see what has been achieved with this material in the construction of bridges, tunnels, piers, harbours, breakwaters, warehouses, lighthouses, and even ships. If we turn to the United States and Germany we are able to see how we have lagged. In both those countries enormous strides have been made and incidentally, in the prosecution of this task, other magnificent conquests in the world of science and of the industrial employment of waste are recorded. To-day the manufacture of cement constitutes one of the twelve most important industries in the United States, and the greater part of this material is made from what a few years ago was accepted as sheer waste—residue from the iron-works which, having no further ostensible use, was dumped in huge piles to the disfigurement of the landscape. To-day this waste is being turned into building material, having usurped the product originally selected for this duty.
The reason why there should be such a deep-rooted antipathy to concrete for house-building purposes in these islands is somewhat inscrutable. Probably it is due to the experiments which were made many years ago, and which owing to our limited knowledge were construed by the quidnuncs into a failure. But because Brunel’s Great Eastern did not succeed we do not laugh at the mammoth steamship of to-day. Brunel’s conception suffered merely from being premature. So were the first attempts to use concrete in the house-building industry. During the past few years we have acquired further knowledge which should enable us to steer clear of the blunders of the past, but instead of grappling with the problem along the lines which science is vividly blazing we prefer to waste time in the idle discussion of quaint theories and fantastic notions.
Many are the reasons why concrete should be employed. In the first place it is difficult to excel for simplicity. It comprises essentially two materials—cement, sand and rubble, the two last-named being generically described as the aggregate. The term is wide in its meaning, comprising virtually any and every inorganic material capable of being crushed to a pre-determined size, and the character of which may be as varied as the number of days in the year or more, while recent investigation has indicated that even the conventional sand may be eliminated, provided a sharp and gritty substitute in a similar powdered form be forthcoming.
Think what this means and the many possibilities it opens up! In the first place it enables material on site—waste—to be turned to economic account, and the term waste in this instance is extremely elastic. There is no need to disfigure the countryside with yawning craters in the form of pits for the excavation of the special clay suited to the making of bricks. Again we must not forget that by the employment of the conventional building materials a demand is made upon transport, which to-day is as acute as the scarcity of houses. With concrete the only constituent calling for transport from a producing point is cement, and this only involves the movement of one-seventh of the load which would otherwise be involved were bricks to be used. In other words, if seven tons of bricks were required to build a house it would only be requisite to move one ton of cement to yield a similar house in concrete—the other six tons of essential materials could be acquired on the site. The avoidance of superfluous expenditure as well as the economy in time and labour is obvious.
Our towns and cities are daily shedding tons of a specific form of waste—ashes and clinker from electric generating stations, water-works, gas-works, and refuse destructors. The contribution naturally varies according to the population, but a small town burning 40 tons of refuse in its destructor may safely anticipate accumulating clinker at the rate of 8 to 10 tons a day. The disposal of this residue presents a problem in itself. A certain quantity can be absorbed in connection with the sewage beds, road-making and other incidental tasks, but, for the most part, it has to be dumped, merely because it possesses no ostensible application. When one reflects upon the activities of the factories in a manufacturing town and the daily output of clinker and ash from these sources alone, it will be seen that the civic clinker disposal problem is likely to assume enormous dimensions, and to prove a costly issue in itself. Thousands of tons are dispatched by road, rail and water from our towns and cities to be jettisoned at suitable points where unsightliness does not count. The authorities of New York City used to ship hundreds of tons daily 60 miles out to sea, while at Liverpool it had to be barged for 24 miles to be thrown overboard into the Irish Sea at a cost of 2s. 6d.—60 cents—a ton! Many borough authorities will readily give away the material to those who care to fetch it, so keen are they to be relieved of this incubus. Yet, in every instance, the equivalent of sovereigns are being shot upon the land, dumped into the sea, or given away as the case may be.
Cannot a more economic use for this and kindred refuse be found? This is the obvious question in this utilitarian age. Yet it is almost superfluous to launch the inquiry. It can be turned into concrete: could, and should, if we were sufficiently enterprising and astute, as well as frugal in our habits, be turned into houses. Certain attempts have been made towards the conversion of this residue into constructional material such as kerb-stones for lining our pavements, slabs to take the place of York flagstones and bricks for paving purposes, the building of sheds and other insignificant structures, but none represents a grim attempt to wrestle with the issue along bold and comprehensive lines.
Some years ago, the city engineer of Liverpool, Mr. John A. Brodie, M.Inst.C.E., one of our most enterprising city engineers, essayed a bigger step forward. He was faced with the disposal of 50,000 tons of clinker from the city destructors during the year. He made a bold effort to turn it to economic account in the obvious directions—paving and kerbing operations—but these channels absorbed only a round 20,000 tons, leaving some 30,000 tons to be shipped to sea to be dumped at a total annual cost of nearly £4,000—$20,000. The city authorities had resolved to carry out a tenement building scheme, and the city engineer decided to provide them in concrete and to use the refuse from the destructors as the aggregate, exacting tests having convinced him of its suitability for this purpose.
The building, covering an area of 3,717 square feet, of which total 1,611 square feet are open space, is of three floors with four tenements on each floor, finished off with a flat roof, surrounded by a parapet for washing, drying, or playground purposes.
The construction of the building was carried out upon the section or slab system. That is to say the walls, floors, ceilings, and other parts, with all necessary openings, were moulded at the destructor works, and set aside for a time to mature. Some of these slabs were of imposing dimensions, ranging up to 16 feet in length by 13 feet wide, 14 inches thick and weighing 11 tons. Upon arrival at the site they were slung into position and dovetailed into place, thus forming a rigid structure.