1911 Encyclopædia Britannica/Building

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BUILDING.[1] The art of building comprises the practice of civil architecture, or the mechanical operations necessary to Relation of building to architecture. carry the designs of the architect into effect. It is not infrequently called "practical architecture," but the adoption of this form would lead only to confusion, by rendering it difficult to make the distinction generally understood between architecture (q.v.) as a fine or liberal art, and architecture as a mechanical art. The execution of works of architecture necessarily includes building, but building is frequently employed when the result is not architectural; a man may be a competent builder without being an architect, but no one can be an accomplished architect unless he be competent to specify and direct all the operations of building. An architect should have a scientific knowledge of the various soils he may meet with, such as clay, earth, silt, rock, gravel, chalk, &c., so that when the trial holes are dug out on the site, he can see the nature of the soil, and at once know what kind of a foundation to put to the building, and the depth to which he must go to get a good bottom. He should also have a good knowledge of chemistry, so that he may understand the effects of the various acids, gases, &c., that are contained in the materials he uses, and the objections to their presence. He must be acquainted with the principles of timbering in trenches, and excavations, shoring, brickwork, fireproof construction, stonework, carpentry and joinery, smiths' work, plumbing, heating, ventilation, bells, electric and gas lighting, water-supply, drainage, plastering, tiling to internal walls or pavings and roofs, slating of roofs, glazing, painting and decoration. He should be able to calculate the various strengths and strains to be placed on any portion of the structure, and have a general knowledge of the building trade, enabling him to deal with any difficulty or defects that may arise.

An important feature in the qualification of the architect is that he should be thoroughly conversant with the by-laws of the different towns or districts, as to the requirements for the various classes of buildings, and the special features of portions of the different buildings. The following are examples of the various buildings which he may have to design, and the erection of which he may have to superintend:—dwelling-houses, domestic buildings, shops, dwellings for the working class, public buildings such as churches, schools, hospitals, libraries and hotels, factories of all kinds for all general trades, studios, electric power stations, cold storage buildings, stables and slaughterhouses. With regard to factories, places for the storage or making of different patent foods, and for slaughter of beasts intended for human consumption, stringent by-laws are in most countries laid down and enforced by the public health authorities. In England, the Public Health Acts and By-laws are carried out by the various borough or district authorities, who appoint inspectors especially to study the health of the public with regard to sanitary arrangements. The inspectors have special powers to deal with all improper or defective food, or with any defects in buildings that may affect its cleanly preparation.

In addition to meeting the requirements of the clients, the various buildings have to be constructed and planned on clearly Reasons for special type of plans. defined lines, according to the rules of the various authorities that control their erection; thus the construction and planning of public schools are governed in England by the board of education, and churches are governed by the various societies that assist in financing the erection of these edifices; of these the Incorporated Church Building Society exercises the strongest control. Factories both in England and France must be planned and erected to meet the separate acts that deal with these buildings. The fire insurance companies lay down certain requirements according to the size of the building, and the special trade for which it is erected, and fix their rate of premium accordingly. Dwelling-houses in London must be erected in accordance with the many building acts which govern the materials to be used, and the methods by which they shall be employed, the thickness of walls, rates of inclination of roofs, means of escape from fire, drainage, space at rear, &c. &c.; these laws especially forbid the use of timber framed buildings. In sundry districts in England where the model by-laws are not in force, notably at Letchworth, Herts, it is possible to erect buildings with sound materials untrammelled by by-laws. With regard to premises used in a combined way, as shop and dwelling-house, if in London, and the building exceeds 10 squares, or 1000 sq. ft. super in area, the stairs and a large portion of the building must be built of fire-resisting materials. In the erection of London flats under certain conditions the stairs and corridors must be of fire-resisting materials, while in parts of New York timber buildings are allowed; for illustrations of these see the article CARPENTRY. In public buildings and theatres in London, Paris and New York not only the construction, but also the exits and seating accommodation and stage, including the scenery dock and flies, must conform to certain regulations.

The conditions necessary for planning a successful building may be summarized as follows:—(1) Ease of access; (2) Good Conditions necessary for a successful building. light (3) Good service; (4) Pleasing environment and approaches; (5) Minimum cost with true economy; in the case of office buildings, also ease of rearrangement to suit tenants. An architect should also be practically acquainted with all the modes of operation in all the trades or arts employed in building, and be able minutely to estimate beforehand the absolute cost involved in the execution of a proposed structure. The power to do this necessarily involves that of measuring work (usually done by the quantity surveyor at an advanced stage of the work), and of ascertaining the quantities to be done. In ordinary practice the architect usually cubes a building at a price per foot cube, as will be described hereafter, but an architect should know how to measure and prepare quantities, or he cannot be said to be master of his profession.

Building includes what is called construction, which is the branch of the science of architecture relating to the practical Construction. execution of the works required to produce any structure; it will therefore be necessary to explain the subject in a general manner before entering upon building in detail.

Although the styles of architecture have varied at different periods, buildings, wherever similar materials are employed, must be constructed on much the same principles. Scientific knowledge of the natures and properties of materials has, however, given to the modern workman immense advantages over his medieval brother-craftsman, and caused many changes in the details of the trade, or art of building, although stones, bricks, mortar, &c., then as now, formed the element of the more solid parts of all edifices.

The object of constructions is to adapt, combine and fit materials in such a manner that they shall retain in use the General principles. forms and dispositions assigned to them. If an upright wall be properly constructed upon a sufficient foundation, the combined mass will retain its position and bear pressure acting in the direction of gravity to any extent that the ground on which it stands, and the compound materials of the wall, can sustain. But pressure acting laterally has a necessary tendency to overthrow a wall, and therefore it will be the aim of the constructor to compel, as far as possible, all forces that can act upon an upright wall, to act in the direction of gravity, or else to give it permanent means of resistance in the direction opposite to that in which a disturbing force may act. Thus when an arch is built to bear against an upright wall, a buttress or other counterfort is applied in a direction opposed to the pressure of the arch. In like manner the inclined roof of a building spanning from wall to wall tends to thrust out the walls, and hence a tie is applied to hold the opposite sides of the roof together at its base, where alone a tie can be fully efficient, and thus the roof is made to act upon the walls wholly in the direction of gravity; or where an efficient tie is inapplicable, as in the case of a hammer beam roof, buttresses or counterforts are added to the walls, to enable them to resist the pressure outwards. A beam laid horizontally from wall to wall, as a girder to carry a floor and its load, may sag or bend downwards, and tend thereby to force out the walls, or the beam itself may break. Both these contingencies are obviated by trussing, which renders the beam stiff enough to place its load on the walls in the direction of gravity, and strong enough to carry it safely. Or if the beam be rigid in its nature, or uncertain in its structure, or both (as cast-iron is), and will break without bending, the constructor by the smiths' art will supply a check and ensure it against the possible contingency.

Perfect stability, however, is not to be obtained with materials which are subject to influences beyond the control of man, and all matter is subject to certain influences of that nature. The Materials. influences mostly to be contended against are heat and humidity, the former of which produces movement of some kind or to some extent in all bodies, the latter, in many kinds of matter; whilst the two acting together contribute to the disintegration or decay of materials available for the purposes of construction. These pervading influences the constructor seeks to counteract, by proper selection and disposition of his materials.

Stone and brick, the principal materials in general construction, keep their places in combination by means of gravity. They may Stone. be merely packed together, but in general they are compacted by means of mortar or cement, so that although the main constituent materials are wholly incompressible, masses of either, or of both, combined in structures are compressible, until the setting medium has indurated to a like condition of hardness. That kind of stone is best fitted for the purposes of general construction which is least absorbent of moisture, and at the same time free to work. Absorbent stone exposed to the weather rapidly disintegrates, and for the most part non-absorbent stone is so hard that it cannot always be used with a due regard to economy. When, therefore, suitable stone of both qualities can be obtained, the harder stone can be exposed to the weather, or to the action which the softer stone cannot resist, and made to form the main body of the structure of the latter so protected. The hard and the soft should be made to bear alike, and should therefore be coursed and bonded together by the mason's art, whether the work be of stone wrought into blocks and gauged to thickness, or of rough dressed or otherwise unshaped rubble compacted with mortar.

Good bricks are less absorbent of moisture than any stone of the same degree of hardness, and are better non-conductors Bricks. of heat than stone. As the basis of a stable structure, brickwork is more to be relied upon than stone in the form of rubble, when the constituents bear the relation to one another last above referred to, the setting material being the same in both; because the brick by its shaped form seats itself truly, and produces by bonding a more perfectly combined mass, whilst the imperfectly shaped and variously sized stone as dressed rubble can neither bed nor bond truly, the inequalities of the form having to be compensated for with mortar, and the irregularity of size of the main constituent accounted for by the introduction of larger and smaller stones. The most perfect stability is to be obtained, nevertheless, from truly wrought and accurately seated and bonded blocks of stone, mortar being used to no greater extent than may be necessary to exclude wind and water and prevent the disintegrating action of these agents upon even the most durable stone. When water alone is to be dealt with, and especially when it is liable to act with force, mortar is necessary for securing to every block in the structure its own full weight, and the aid of every other collateral and superimposed stone, in order to resist the loosening effect which water in powerful action is bound to produce.

In the application of construction to any particular object, the nature of the object will naturally affect the character of Particular objects of construction. the constructions and the materials of which they are to be formed. Every piece of construction should be complete in itself, and independent as such of everything beyond it. A door or a gate serves its purpose by an application wholly foreign to itself, but it is a good and effective, or a bad and ineffective, piece of construction, independently of the posts to which it may be hung, whilst the wheel of a wheelbarrow, comprising felloes, spokes and axletree, is a piece of construction complete in itself, and independent as such of everything beyond it. An arch of masonry, however large it may be, is not necessarily a piece of construction complete in itself, for it would fall to pieces without abutments. Thus a bridge consisting of a series of arches, however extensive, may be but one piece of construction, no arch being complete in itself without the collateral arches in the series to serve as its abutments, and the whole series being dependent thereby upon the ultimate abutments of the bridge, without which the structure would not stand. This illustration is not intended to apply to the older bridges with widely distended masses, which render each pier sufficient to abut the arches springing from it, but tend, in providing for a way over the river, to choke up the way by the river itself, or to compel the river either to throw down the structure or else to destroy its own banks.

Some soils are liable to change in form, expanding and contracting under meteorological influences; such are clays which Foundations. swell when wetted and shrink when dried. Concrete foundations are commonly interposed upon such soils to protect the building from derangement from this cause; or walls of the cheaper material, concrete, instead of the more expensive brick or stone structure, are brought up from a level sufficiently below the ordinary surface of the ground. When concrete is used to obviate the tendency of the soil to yield to pressure, expanse or extent of base is required, and the concrete being widely spread should therefore be deep or thick as a layer, only with reference to its own power of transmitting to the ground the weight of the wall to be built upon it, without breaking across or being crushed. But when concrete is used as a substitute for a wall, in carrying a wall down to a low level, it is in fact a wall in itself, wide only in proportion to its comparative weakness in the absence of manipulated bond in its construction, and encased by the soil within which it is placed. When a concrete wall is used in place of brick the London Building Act requires an extra thickness of one-third; on the question of reinforced concrete no regulations as to thickness have at present been made.

The foundation of a building of ordinary weight is for the most part sufficiently provided for by applying what are technically Footings to walls. termed "footings" to the walls. The reason for a footing is, that the wall obtains thereby a bearing upon a breadth of ground so much greater than its own width or thickness above the footing as to compensate for the difference between the power of resisting pressure of the wall, and of the ground or ultimate foundation upon which the wall is to rest. It will be clear from this that if a building is to be erected upon rock as hard as the main constituent of the walls theoretically no expanded footings will be necessary; if upon chalk, upon strong or upon weak gravel, upon sand or upon clay, the footing must be expanded with reference to the power of resistance of the structure to be used as a foundation; whilst in or upon made ground or other loose and badly combined or imperfectly resisting soil, a solid platform bearing evenly over the ground, and wide enough not to sink into it, becomes necessary under the constructed footing. For this purpose the easiest, the most familiar, and for most purposes the most effectual and durable is a layer of concrete.

The English government, when it has legislated upon building matters, has generally confined itself to making provision that the enclosing walls of buildings should be formed of incombustible materials. In provisions regarding the least thicknesses of such walls, these were generally determined with reference to the height and length of the building.

In the general and usual practice of developing land at the present day, the owner or freeholder of the land first consults an Procedure for an intended building. architect and states his intentions of building, the size of what he requires, what it is to be used for, if for trade how many hands he intends to employ, and the sub-buildings and departments, &c., that will be wanted. The architect gathers as much information as he can as to his client's requirements, and from this information prepares his sketches. This first step is usually done with rough sketches or outlines only, and when approved by the client as regards the planning and situation of rooms, &c., the architect prepares the plans, elevations, and sections on the lines of the approved rough sketches; at the same time he strictly observes the building acts, and makes every portion of the building comply with these acts as regards the thickness of walls, open spaces, light and air, distances from surrounding property, frontage lines, and a host of other points too numerous to mention, as far as he can interpret the meaning of the enactments. (The London and New York Building Acts are very extensive, with numerous amendments made as occasion requires.) An architect, whilst preparing the working drawings from the rough approved sketches, and endeavouring to conform with the Building Act requirements, often finds after consultation with the district surveyor, or the London County Council, or other local authorities, that the plans have to be altered; and when so altered the client may disapprove of them, and thus delay often occurs in settling them.

Another important point is that after the architect has obtained the consent of the building authorities, and also the approval of the client, then he may have to fight the adjoining owners with regard to ancient lights, or air space, or party walls. In the city of London these last difficulties often mean the suspension of the work for a long time, and a great loss to the client.

If the site is a large one, or the nature of the soil uncertain, trial holes should be sunk directly the sketch plans are approved. (See FOUNDATIONS.)

Where the property is leasehold there are always at this stage negotiations as to obtaining the approval of the senior lessors and the freeholders; these having been obtained, the architect is then free to serve the various notices that may be required re party walls, &c.

The contract plans should be very carefully prepared, and sections, plans and elevations of all parts of the buildings and the levels from a datum line be given. In addition to the general set of drawings, larger scale details of the principal portions of the building should be given.

If there are any existing buildings on the site these should be carefully surveyed and accurate detail plans be made for reference; this is especially necessary with regard to easements and rights of adjoining owners. Also in the preparation of the site plan the various levels of the ground should be shown.

The plans having been approved by all parties concerned, the next operation is the preparation of the specification. This is a document which describes the materials to be used in the building, states how they are to be mixed, and how the various works are to be executed, and specifies every trade, and every portion of work in the building. The specification is necessary to enable the builder to erect the structure according to the architect's requirements, and is written by the architect; usually two copies of this document are made, one for the builder, the other for the architect, and the latter is signed as the contract copy in the same manner as the drawings.

From the specification and drawings usually an approximate estimate of the cost of the proposed building is prepared by the architect, and the most general method adopted is to cube the building by a multiplication of the length, breadth and height of the building, and to multiply the product or cubic contents by a price ranging from fivepence to three shillings per cubic foot. In the case of churches, chapels and schools, the cost may be roughly computed by taking the number of seats at a price per seat. In the case of churches and chapels, taking a minimum area of 8 ft. each, the cost varies from £10 upwards, the difference being due to the amount of architectural embellishment or the addition of a tower. Schools may be estimated as averaging £9 per scholar; we find that, taking schools of various sizes erected by the late London School Board, their cost varied from £7:12:4 to £10:1:10 per scholar. Hospitals vary from £100 per bed upwards, the lowest cost being taken from a cottage hospital type; while in the case of St Thomas's hospital, London, the cost per bed, including the proportion of the administrative block, was £650, and without this portion the wards alone cost £250. The Herbert hospital at Woolwich cost only £320 per bed.

The bills of quantities are prepared by the quantity surveyor, and are generally made to form part of the contract, and so mentioned in "the contract." The work of the quantity surveyor is to measure from the drawings the whole of the materials required for the structure, and state the amounts or quantities of the respective materials in the form of a bill usually made out on foolscap paper specially ruled, so that the builders can price each item, together with the labour required to work and fix it, thus forming the building. The idea is to be able to arrive at a lump sum for which the builders will undertake to erect the building. It is of frequent occurrence, in fact it occurs in four-fifths of building contracts, that when a building is commenced, the client, or other interested person, will alter some portion, thereby causing deviations from the bills of quantities. By having the prices of the different materials before him, it is easy for the quantity surveyor to remeasure the portion altered, adding or deducting as the case may be, and thus to ascertain what difference the alteration makes. This method of bills of quantities and prices is absolutely necessary to any one about to build, and means a considerable saving to the client in the end. For example:—Suppose that bills of quantities are not prepared for a certain job by a quantity surveyor, and, as is often done, the drawings and specification are sent to several builders asking them for a quotation to build the house or factory or whatever it may be, according to the drawings and specification. The prices are duly sent in to the architect, and probably the lowest price is accepted and the successful builder starts the job. During the progress of the works certain alterations take place by the owner's instructions, and when the day of settlement comes, the builder puts in his claim for "extras," then owing to the alterations and to the architect having no prices to work upon, litigation often ensues.

Before the work of erecting a structure is entrusted to a builder he has to sign a contract in the same manner as the drawings and specification. This contract is an important document wherein the builder agrees to carry out the work for a stated sum of money, in accordance with the drawings and specification, and bills of quantities, and instructions of the architect, and to his entire satisfaction; and it also states the description of the materials and workmanship, and the manner of carrying out the work, responsibilities of the builder, particularly clauses indemnifying the employer against accidents to employees, and against numerous other risks, the time of completion of works under a penalty for non-completion (the usual allowance being made for bad weather, fire or strikes), and also how payments will be made to the builder as he proceeds with the building. This form of contract is generally prepared by the architect, and varies in part as may be necessary to meet the requirements of the case.

When the drawings have been approved by the owner or client, also by the district surveyor or local authorities, and by adjoining owners, one copy of them, made on linen, is usually deposited (in London) either with the district surveyor, or with the London County Council, another is prepared for the freeholder if a lease of the land is granted, and a third is given to the builder. In addition, in complicated cases such as occur in the city of London, when a building is erected on land which has four or five distinct owners, an architect may have to prepare a large number of complete copies to be deposited with the various parties interested.

The duties of the builder are very similar to those of the architect, except that he is not expected to be able to plan The builder's sphere. and design, but to carry out the plans and designs of the architect in the actual work of building. The builder should also know the various acts, and in particular the acts specially relating to the erection of scaffoldings, hoardings, gantries, shoring and pulling down of old buildings. He should have a thorough knowledge of all materials, their qualifying marks or brands, and the special features of good and bad in each class, their uses and method of use. He should be able to control and manage both the men and materials; and briefly, in a builder, as opposed to an architect, the constructive knowledge should predominate.

On large or important works it is usual to have a clerk of works or delegate from the architect; his duties are to be on the works while they are in progress and endeavour by constant attention to secure the use of the best materials and construction, and to report to the architect for his instruction any difficulties that may arise. He should be a thoroughly practical man as opposed to the architectural draughtsman. His salary is paid by the client, and is not included in the architect's remuneration.

American building acts agree in a general manner with those enforced in London. But whereas New York allows the erection American practice. of frame or wood structures, while defining a certain portion of the city inside which no new frame or wood structures shall be erected, in London and the large cities of Great Britain the erection of wood frame buildings as dwellings is prohibited. In New York City provision is made for a space at the rear of domestic buildings at least 10 ft. deep, but such depth is increased when the building is over 60 ft. high, and is varied under special circumstances. In London this depth is the same, but the height of the building in relation to the space required in the rear thereof shall be constructed to keep within an angle of 63½ degrees, inclining from the rear boundary towards the building from the level of pavement in front of building; the position from which the angle is taken is varied under special circumstances. In the smaller English towns the building regulations are framed on the model by-laws, and these increase the depth of the yard or garden according to the height of the building.

With regard to the strength and proportion of materials, these are not dealt with in the London Building Act to the same extent as in the New York; for example, in the New York acts (parts 4 and 5)[2] it is prescribed that the bricks used shall be good, hard, well-burned bricks. The sand used for mortar shall be clean, sharp, grit sand, free from loam or dirt, and shall not be finer than the standard samples kept in the office of the department of buildings; also the quality of lime and mortar is fully described, and the strengths of steel and cast-iron, and tests of new materials. Also it is required that all excavations for buildings shall be properly guarded and protected so as to prevent them from becoming dangerous to life or limb, and shall be sheath-piled where necessary by the person or persons causing the excavations to be made, to prevent the adjoining earth from caving in. Plans filed in the department of buildings shall be accompanied by a statement of the character of the soil at the level of the footings. There are also requirements as to protecting adjoining property. The bearing capacity of soils, pressure under footings of foundations, and in part 6 the materials of walls and the methods to be observed in building them are defined. Part 23 deals with floor loads, and the strength of floors constructed of various materials, and requires that the temporary support shall be strong enough to carry the load placed upon them during the progress of any works to buildings. Part 24 deals with the calculations and strength of materials, and wind pressure. Parts 4 and 5 of the New York Building Code are not dealt with by the London Building Act, but the local by-laws of the various districts deal with these. Part 6 of the New York code is dealt with partly by the London Building Act, and partly by the local by-laws. Parts 23 and 24 of the New York code are not dealt with in the English acts at all. In America the standard quality for all materials is set out, but in no English acts do we find the definition of the quality of timber, new materials, steel, &c. Iron and steel construction is in its infancy in England as compared with America, and probably this accounts for no special regulations being in force; but part 22 of the New York Building Code, section 110 to 129 inclusive, deals very fully with iron and steel construction, and this is further supplemented by sections 137 to 140 inclusive.

Sanitary work is dealt with in London by section 39 of the Public Health (London) Act, and the drainage by-laws of the London County Council, in which every detail is very fully gone into with regard to the laying of drains, and fitting up of soil pipes, w.c.'s, &c., all of which is to be carried out and tested to the satisfaction of the local borough's sanitary inspector. The general requirements of New York with regard to sanitary work are very similar with a few more restrictions, and are carried out under "the rules and regulations for plumbing, drainage, water-supply, and ventilation of buildings." The noticeable feature of the New York regulations is that all master plumbers have to be registered, which is not so in England. The New York regulations have 183 sections relating to sanitary work, and the English regulations have 96 sections. Also by part 16 of the Amendments to Plumbing Rules 1903, the New York laws require that, before any construction of, or alterations to, any gas piping or fittings are commenced, permits must be obtained from the superintendent of buildings; these are only issued to a registered plumber. The application must be accompanied by plans of the different floors showing each outlet, and the number of burners to each outlet; a statement must also be made of the quality of the pipes and fittings, all of which are to be tested by the inspector. In London there are no such laws; the gas companies control a small portion of the work as regards the connexion to meters, while the insurance companies require gas jets to be covered with a wire guard where liable to come in contact with inflammable goods. As to water, the various water companies in England have each their own set of regulations as to the kind of fittings and thickness and quality of pipe to be used, whether for service, wastes or main.

The importance of fire-resisting construction is being more fully recognized now by all countries. In France the regulations Fire-resisting construction. for factories, shops and workshops relating to "exits" require that all doors should open outwardly when they open on to courts, vestibules, staircases or interior passages. When they give access to the open air, outward opening is not obligatory unless it has been judged necessary in the interests of safety. If the doors open on to a passage or staircase they must be fixed in such a manner as not to project into the passage or staircase when open. The exits must be numerous, and signs indicating the quickest way out are to be placed in conspicuous positions. The windows are to open outwardly. Staircases in offices or other buildings serving as places for work shall be constructed in incombustible materials, or shall be walled in fully in plaster. The number of staircases shall be in proportion to the number of employees, &c. It is prohibited to use any liquid emitting vapours inflammable under 35° C. for the purpose of lighting or heating, unless the apparatus containing the liquid is solidly closed during work, that part of the apparatus containing the liquid being so closed as to avoid any oozing out of the liquid, &c. &c. Instructions are added as to precautions to be taken in case of fire.

In London fire-resisting construction is dealt with in the London Building Act, and its second schedule, and in London County Council Theatre and Factory Acts, &c. In New York the building code (parts 19, 20 and 21) deals with fire appliances, escapes, and fire-proof shutters and doors, fire-proof buildings and fire-proof floors, and requires that all tenement houses shall have an iron ladder for escape. A section somewhat similar to the last came into force in London in 1907 under the London Building Act, being framed with a view to require all existing projecting one-storey shops to have a fire-resisting roof, and all existing buildings over 50 ft. in height to have means of escape to and from the roof in case of fire.

There are several patents now in use with which it would be possible to erect a fire-proof dwelling at small cost with walls 3 to 5 in. in thickness. One of these has been used where the building act does not apply, as in the case of the Newgate prison cells, London, where the outside walls were from 3 to 4 in. thick only, and were absolutely fire and burglar proof. This method consists in using steel dovetailed sheets fixed between small steel stanchions and plastered in cement on both sides. This form of construction was also used at the British pavilion, Paris Exhibition 1900, and has been employed in numerous other buildings in England, and also in South Africa, Venezuela, and India (Delhi durbar). The use of many of these convenient and sound forms of building construction for ordinary buildings in London, and in districts of England where the model by-laws are in force, is prohibited because they do not comply with some one or other of the various clauses relating to materials, or to the thickness of a wall.

The various details of construction are described and illustrated under separate headings. See BRICKWORK, CARPENTRY, FOUNDATIONS, GLAZING, JOINERY, MASONRY, PAINTER-WORK, PLASTERING, ROOFS, SCAFFOLD, SHORING, STAIRCASE, STEEL CONSTRUCTION, STONE, TIMBER, WALL-COVERINGS, &c.

The principal publications for reference in connexion with this subject are: The Building and Health Laws of the City of New York, Brooklyn Eagle Library, No. 85; Rules and Regulations affecting Building Operations in the administrative County of London, compiled by Ellis Marsland; Annotated By-Laws as to House Drainage, &c., by Jensen; Metropolitan Sanitation, by Herbert Daw.

(J. BT.)

Endnotes[edit]

1 ^  The verb "to build" (O.E. byldan) is apparently connected with O.E. bold, a dwelling, of Scandinavian origin; cf. Danish bol, a farm, Icelandic ból, farm, abode. Skeat traces it eventually to Sanskrit bhu, to be, build meaning "to construct a place in which to be or dwell."

2 ^  Building and Health Laws and Regulations affecting the City of New York, including the Building Code of New York City as amended to 1st May 1903.