By S. KAMESAM, Timber Constructional Engineer, Bangalore, Associate Delegate for India
IT IS questionable whether the present shortage of timber supplies in the more developed countries of Asia, for example India, is actual or relative. The situation may have arisen and may persist through lack of an efficient policy of integrated and scientific structural and industrial utilization of timber planned to obviate waste in conversion and utilization.* In the past such a policy has been conspicuously absent and owing to wrong engineering design and the use of untreated timber, we have been wasting timber on a colossal scale. If the problem of utilization is tackled properly, and if the timber "surplus" countries of Southeast Asia co-operate with the "deficit" countries, there need be no apprehension over a timber famine or over inadequate supplies in the coming years for even large-scale industrial development.
*Note: Considerable work has been carried out by the United Nations Economic Commission for Europe, through its Housing Subcommittee and Timber Committee, on economies to be achieved in timber consumption. A report on Possible Timber Economies in Construction has been prepared. FAO, through the chairman of its Mechanical Wood Technology Committee, is completing a study on more rational wood utilization. The United Nations, also, is devoting increasing attention to the whole field of housing and town and country planning. - Editor.
This article deals with three important problems that face Asia today: (1) fuel for urban areas, (2) timber for rural housing and other rural needs, and (3) structural timber for urgent industrial development schemes and for the maintenance of existing public utilities.
URBAN FUEL NEEDS
Owing to the urgent demand for posts and fuel by the military during the last war, fuel resources near towns and cities have reached almost the exhaustion point and today urban fuel requirements often have to be transported over a hundred miles. These long hauls for the transport of fuelwood have thrown an additional burden on the railways which, owing to neglected maintenance, are hardly fit to take even the strain of normal traffic. There are cities in the region which, in spite of special and very useful organizations for maintaining fuel reserves, have on some occasions been faced with real fuel starvation. A solution would be the exclusive use of charcoal instead of fuelwood in urban areas. But in India, for example, the annual production of 9 million tons of charcoal is produced by the most primitive methods. It is most necessary, not only for reducing the weight of fuelwood to be carried by railways to towns and cities, but also for the conservation of natural resources, that a well-integrated scheme of modern wood carbonization, recovering all the by-products, should be considered. The Swiss Strupp process, the "circulating gas method," deserves special mention here. It is essential also, of course, to develop efficient charcoal-burning stoves and ovens for use in urban areas and to provide for their mass production. These should be sold on a non-profit basis by governments direct to the people.
In places where cheap hydroelectric power is available, full advantage should also be taken of this source of energy for heating and cooking. In most countries of the region the heating required is small as the cold season is rarely of long duration.
The growing of municipal or community forests within as short a distance as possible from built-up areas is recommended. Quick-growing fuel species, which can be harvested once every five years, should be planted at the beginning of the monsoon. The possibility of using tree-planting machines - even helicopters for carrying seedlings to areas not connected by roads, or airplanes for broadcast sowing of seeds - should be investigated.
TIMBER FOR RURAL HOUSING AND OTHER RURAL NEEDS
Ninety percent of the population of India and Pakistan, and of some other Asiatic countries, lives in villages, where the housing conditions are appalling and a disgrace to modern civilization. The flooring of the house is most insanitary, consisting of mud "stabilized" by repeated coatings of cow dung, which acts as a nutrient medium for the growth of bacteria and insects responsible for many tropical diseases. The walls consist mostly of mud or mud plastered over untreated bamboo or poor timber. There are probably a few sapwood posts imbedded in the mud walls, and also smaller posts serving as door frames and frames of windows, if windows are provided at all. The ground being infested with white ants, the timber or bamboo members last hardly two or three years when the whole structure has to be rebuilt. The roof consists again of sapwood poles or posts, split or unsplit bamboos, bamboo matting or palm leaves. Such roofing is tinder-dry before the onset of the monsoon and highly inflammable, and in other seasons of the year gives refuge to snakes, scorpions, and poisonous spiders, which take a heavy toll of lives every year in the tropics. Gradually destroyed by termites and rot, these roofs often collapse suddenly during storms.
The villager therefore lives in a very unhygienic and uncomfortable home, with the most elementary protection against sun, rain and wind. How can man rise to normal stature in such surroundings?
With the present timber shortage that is spoken of, is there any possibility for improving these homes? Many people seem to reply "No." India is trying to import from America aluminum for house frameworks and roof trusses. But the country is faced with a $2,500 million shortage this year and the need to buy 2 million tons of food from abroad. It is also endeavoring to import steel at exorbitant prices. These metals are not needed. An interim solution to the problem of rural housing in Asia could be based, to a large extent, on the integrated and scientific utilization of the bamboo resources of the region.*
*A positive approach to the problem of housing in the tropics appears in "Huts and Houses in the Tropics," Unasylva, Vol. III, No. 3, p. 100.
This could be the best approach for solving the housing problem of 95 percent of the population. There are more than adequate bamboo resources remaining unexploited in the region for all the housing required. Bamboo becomes mature within a period of four to five years, so that this structural material, nature's cheapest box-girder, can be harvested on a five-year rotation. The exploitation of bamboo does not call for any expensive or intricate machinery, and its transportation is easy with the millions of bullock carts and floating streams available in the region. All that is needed is standardization, prefabrication, and mass production of building elements after architects and engineers have developed aesthetic designs of different types of rural houses. The knowledge of how to make these houses already exists. The roofs present certain difficulties but these are certainly not insuperable and there are several designs suitable for immediate adoption, even in areas of high wind pressure or high rainfall. Engineers may well consider the possibilities for economy and efficiency in using laminated wood or bamboo "boomerang arches," so that the hinges are at ground level and the walls and roofing form a continuous surface.
There are other timber requirements in villages which deserve a passing mention, and here also the possibilities of standardization, prefabrication, and even mass production should be borne in mind. The question of supplying a more scientifically designed, strong and durable bullock cart to villagers is most important. Again, every villager has one or two plows that could be better designed and mass produced for improved performance, greater durability, and lower cost. Properly preserved fence posts and fencing could replace the millions of cubic feet of fencing which are eaten up annually by termites or borers.
Nobody ever seems to think of furniture for villagers, but if standards of living are to be improved, the villager should not only be provided with good dwellings but also with his elementary needs in rural furniture. The state should put up factories for the mass production of such furniture.
INDUSTRIAL UTILIZATION OF WOOD
The question of providing timber for industrial purposes is a most extensive subject. The Government of India is preparing a comprehensive scheme for the use of treated wood and bamboo in place of steel, which today is the "kingpin" of industrial development. Five or six important aspects of industrial construction will be dealt with in the present article.
RAILWAY SLEEPERS
At present, in many countries of this region, not only the bulk of the timber but also its "cream" is commandeered for sleepers by the governments who almost invariably own the railways. It seems absurd that a first priority should in this way be given to railway sleepers which are most primitive in design. Until recently not only have the best grades of timber been appropriated but also the most durable species, like teak. The cross section of the sleepers was fixed nearly a hundred years ago when easily accessible virgin forests were still standing. A cross section of, for example, 10 inches x 5 inches (25 x 13 cm.) for India, requiring about 340,000 m³ (s) (12 million cubic feet) of straight-grained and well seasoned timber annually, seems to involve a colossal waste, as for this cross section not only very large-sized trees and tree portions must be used but there is a wastage of nearly 50 percent of the log in conversion. The so-called "flats" left after sleeper conversion are either burnt in the jungle or left to decay. The same width and number of sleepers per mile are used in Asia as in temperate countries although some of the Asian hardwoods have 50 to 75 percent more strength than the hardwood or softwood sleepers used in other countries. The possibility of saving at least 30 to 40 percent of timber in railway sleepers, and the reduction of waste during the conversion of logs from 50 to 10 percent should be fully explored, as well as the fabrication of sleepers using poorer grades and smaller sized timbers. No sapwood of any timber should be rejected, as with impregnation it can be as durable as the heartwood.
ELECTRICAL, TELEGRAPH AND TELEPHONE SUPPORTS
Cheap hydroelectric power will be the means for extensive industrial development in Asia and a number of electrification schemes are now being considered or undertaken by most of the governments in the region. These require large numbers of electrical transmission, distribution, and telegraph and telephone poles, varying generally in length from 20-36 feet (6-11 meters) with butt diameters from 6-12 inches (15-30 cm.). These posts would have to be pressure preserved. Besides these posts, hundreds of thousands of cross arms for supporting the wires are also required. These can, in many cases, be cut from the "flats" left after sleeper conversion and can be specified with sleeper indents.
There are one or two aspects of pole design which have been curiously lost sight of in most countries and which could save initially about 30 percent of timber, besides about an equal proportion of wood preservative. The possibility of the use of "half moon" section poles deserves close examination. The present practice of using a section with equal strength in all directions is obviously a waste of material. The use of a tapering or built-up pole, especially for longer lengths and the designing of poles according to regional specifications instead of for a country as a whole may perhaps save up to 50 or 60 percent of the timber now used. The same dimensions of poles as are used in America have been used in Asia for tens of thousands of poles although the strength of the Asian timber is two and one-half times as much as that in America.
Extraction of poles from mountain regions in lengths greater than 12 or 15 feet (3.7 or 4.6 meters) is often difficult. Their utilization therefore depends on the design of a suitable pole joint which has already been worked out. The impregnation of a butt section, approximately equal to a quarter of the length of the pole, would preserve that section for 30 to 40 years. The remaining portion of the pole exposed to much less severe service conditions, could be impregnated not only with a lighter treatment but with a wood preservative more efficient in resistance to volatilization than to leaching. Gallons of wood preservative could be saved by adopting this suggestion. The use of solid bamboos for electrical, telegraph, and telephone supports is now possible.
INDUSTRIAL BUILDINGS
The use of "rigid types" of arches, pole trusses, with or without bamboo composite construction, should be introduced on a large scale. If such timber or bamboos are pressure preserved, they can give an almost indefinite period of life with no maintenance costs. They can easily be made highly fire resistant by either suitable impregnation or the application of a fireproofing paint. There is no justification for the use of steel, which requires to be protected annually by paint; for large-span roof trusses up to 200 feet (60 meters), purling, etc. In some eases there is also no need for cement or steel or even bricks for walls if the suggestion for "boomerang arches" made earlier in this article be seriously considered.
MARINE CONSTRUCTION
More than 95 per cent of the marine front of the United States of America consists of pressure-treated wood piles, fenders, decking, etc. All-wood ships are being built in several countries, up to an ocean tonnage of 3,000. By proper utilization, countries in Asia should be able to develop their timber resources for meeting marine requirements in this direction.
URBAN HOUSING
The remarks made in the section dealing with rural housing apply here with equal force. The need for standardization and prefabrication of doors and window frames and shutters, built-in furniture, and housing components, designed on a modular basis, is important. The present trend of design, based completely on structural postulates, is hardly correct. Sociological factors and not merely factors of strength and tradition should determine the design of urban housing as well as the choice of building materials. The present general trend of housing design in India has remained practically the same for a century. Housing design in India should follow the lines of that in Japan, where the whole house is built of light material, wood and bamboo, with some light plaster, and not designed as a "fort" with iron bars for all windows. Houses in Asia should be durable, to last 2530 years, but should be light and elastic, consisting of building elements whose size and position can be easily and inexpensively changed.
While during the last century the father built a massive house where his children, grandchildren, and great grandchildren all might live it has become almost general that the son seldom lives in the house built by his father and that the father himself would like to change the design of the house periodically, according to the needs of the family and the member of members living in the house. The need for "extensible" and "reducible" houses is becoming more urgent. With a rising standard of living and a rising cost of labor for maintaining a house, this factor will gradually become increasingly important in the East.
The cross sections of door and window frames and the thickness of door and window shutters used in India have remained the same for nearly a hundred years, with hardly any basis in engineering design. The thickness of materials used for door and window shutters, for instance, could be reduced by about 50 percent. The present cross sections of beams, rafters, purling, used in open house construction are highly wasteful. They are a legacy of the carpenters' age when the carpenter performed the functions of an engineer. A third of the timber used at present could be saved by proper design with very little machine fabrication. The use of laminated beams could make a further saving of 15 percent. Wood is the proper material for building houses in Asia. Its high strength in relation to weight, the ease with which it can be cut and altered on the spot with simple hand tools, its relatively high thermal insulation capacity, its high durability when treated, lead to low maintenance costs. Its relatively low initial costs and its high aesthetic appeal are all factors in favor of its selection.
HIGHWAY BRIDGES
Designs now existing make it possible to erect in Asia highway bridges of any span up to 70 feet (21 meters), using local material and local labor and carpentry tools which local artisans, even in villages, have long been adept at using. Any extensive program of rural development is necessarily linked with the extension of rural high ways which automatically means construction of numerous bridges.
RELATIVE ECONOMY OF TREATED WOOD, STEEL, AND CONCRETE
The present tendency of engineers to pin their faith on the so-called permanent materials like reinforced concrete and steel is a fallacy. At the rate that technical innovations and revolutionary scientific developments have been taking place during the last two decades, there is little doubt that most structures including houses, will become obsolete in another 30 years. Some may have to be scrapped within an even shorter period. Assuming then that the obsolescent period of most structures is 30 years, the use of treated wood and bamboo is more economical than use of steel or reinforced concrete in the case of practically every structure.
In this article the chemical utilization of timber has not been touched on. Nor has the necessity of reorientating forest policies in line with improved utilization, but the writer believes that there need be no serious apprehension of a timber shortage in practically any Asiatic country. By timber engineering one cubic meter ® can do the work of two cubic meters ®. By pressure wood preservation, one cubic meter can do the work of ten or twenty cubic meters. By substituting split or solid bamboo for wood, thousands of cubic meters of timber can be saved. More thousands of cubic meters can be saved by standardization, prefabrication, and by mass production methods. Those who aim at the maximum of public economy should make sure that no false economy or enslavement to tradition is permitted to thwart their judgment in the selection of structural materials.
