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51-678: Sonti Kamesam (1890–30 November 1952) was an Indian timber engineer and scientist who worked at the Forest Research Institute, Dehra Dun. He is best known for his patented wood preservative, ASCU , from the chemical symbols for Arsenic and Copper. The treatment was patented in Britain from 1934 and in the US from 1938. It also went by the name of Chromated Copper Arsenate or CCA in the United States of America from around

102-652: A rip saw is the most common method, because sawing allows logs of lower quality, with irregular grain and large knots, to be used and is more economical. There are various types of sawing: Dimensional lumber is lumber that is cut to standardized width and depth, often specified in millimetres or inches (but see below for information on nominal dimensions vs. actual dimensions). Carpenters extensively use dimensional lumber in framing wooden buildings. Common sizes include 2×4 (pictured) (also two-by-four and other variants, such as four-by-two in Australia, New Zealand, and

153-462: A "class 1 flame spread rating of 25 or less, when tested in accordance with ASTM standard E 84," which means it burns more slowly than almost all treated wood lumber. A timber mark is a code beaten on to cut wood by a specially made hammer to show the logging licence. The basic understanding of lumber, or "sawn planks", came about in North America in the seventeenth century. Lumber is

204-400: A 1-inch-thick (25 mm) board, 8/4 (eight quarter) is a 2-inch-thick (51 mm) board, etc. This "quarter" system is rarely used for softwood lumber; although softwood decking is sometimes sold as 5/4, even though it is actually one inch thick (from milling 1 ⁄ 8  in or 3.2 mm off each side in a motorized planing step of production). The "quarter" system of reference is

255-534: A 10-foot-long (3.0 m) 2×4 ( 1 + 1 ⁄ 2 by 3 + 1 ⁄ 2  in or 38 by 89 mm) into two 1×4s ( 3 ⁄ 4 by 3 + 1 ⁄ 2  in or 19 by 89 mm) of the same length is considered re-sawing. Structural lumber may also be produced from recycled plastic and new plastic stock. Its introduction has been strongly opposed by the forestry industry. Blending fiberglass in plastic lumber enhances its strength, durability, and fire resistance. Plastic fiberglass structural lumber can have

306-424: A booklet on Construction of Better and cheaper highway bridges in 1943. Timber Lumber is wood that has been processed into uniform and useful sizes (dimensional lumber), including beams and planks or boards . Lumber is mainly used for construction framing , as well as finishing (floors, wall panels , window frames ). Lumber has many uses beyond home building. Lumber is referred to as timber in

357-472: A framer much time, because they are pre-cut by the manufacturer for use in 8-, 9-, and 10-foot ceiling applications, which means the manufacturer has removed a few inches or centimetres of the piece to allow for the sill plate and the double top plate with no additional sizing necessary. In the Americas, two-bys (2×4s, 2×6s, 2×8s, 2×10s, and 2×12s), named for traditional board thickness in inches, along with

408-438: A highway bridge with a 60-foot span. In order to prove the strength of the bridge, he made two adult elephants, each weighing in at around ten tons, walk across while his children stood underneath. After retirement Kamesam joined Tiruvankur estate as director of the development department. He built many bridges with his preserved wood. He was awarded an honorary D.Sc. by Andhra University for his contributions in 1939. He wrote

459-399: A relatively small set of specified lengths; in all cases hardwoods are sold to the consumer by the board-foot (144 cubic inches or 2,360 cubic centimetres), whereas that measure is not used for softwoods at the retailer (to the cognizance of the buyer). Also in North America, hardwood lumber is commonly sold in a "quarter" system, when referring to thickness; 4/4 (four quarter) refers to

510-452: A timber is referred to as one "timber" (材), and the dimensions of other structural components were quoted in multiples of "timber"; thus, as the width of the actual timber varied, the dimensions of other components were easily calculated, without resorting to specific figures for each scale. The dimensions of timbers in similar applications show a gradual diminution from the Sui dynasty (580–618) to

561-443: A traditional North American lumber industry nomenclature used specifically to indicate the thickness of rough sawn hardwood lumber. In rough-sawn lumber it immediately clarifies that the lumber is not yet milled, avoiding confusion with milled dimension lumber which is measured as actual thickness after machining. Examples – 3 ⁄ 4 -inch, 19 mm, or 1x. In recent years architects, designers, and builders have begun to use

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612-426: A unit of dimensional lumber is limited by the height and girth of the tree it is milled from. In general the maximum length is 24 ft (7.32 m). Engineered wood products, manufactured by binding the strands, particles, fibers, or veneers of wood, together with adhesives, to form composite materials, offer more flexibility and greater structural strength than typical wood building materials. Pre-cut studs save

663-515: Is a constant need for density and thickness monitoring and gamma-ray sensors have shown good performance in this case. Certain species of softwood are more resistant to insect attack from woodworm , as certain insects prefer damp hardwood. Softwood is the source of about 80% of the world's production of timber , with traditional centres of production being the Baltic region (including Scandinavia and Russia ), North America and China. Softwood

714-419: Is available in many species, including hardwoods and softwoods , such as white pine and red pine , because of their low cost. Finished lumber is supplied in standard sizes, mostly for the construction industry – primarily softwood , from coniferous species, including pine , fir and spruce (collectively spruce-pine-fir ), cedar , and hemlock , but also some hardwood, for high-grade flooring. It

765-543: Is critical, such as trusses , rafters , laminating stock, I-beams and web joints. Machine grading measures a characteristic such as stiffness or density that correlates with the structural properties of interest, such as bending strength . The result is a more precise understanding of the strength of each piece of lumber than is possible with visually graded lumber, which allows designers to use full-design strength and avoid overbuilding. In Europe, strength grading of rectangular sawn lumber/timber (both softwood and hardwood)

816-633: Is done according to EN-14081 and commonly sorted into classes defined by EN-338. For softwoods, the common classes are (in increasing strength) C16, C18, C24, and C30. There are also classes specifically for hardwoods and those in most common use (in increasing strength) are D24, D30, D40, D50, D60, and D70. For these classes, the number refers to the required 5th percentile bending strength in newtons per square millimetre. There are other strength classes, including T-classes based on tension intended for use in glulam . Grading rules for African and South American sawn lumber have been developed by ATIBT according to

867-435: Is enormous variation with the range of wood hardness of the two groups overlapping. For example, balsa wood, which is a hardwood, is softer than most softwoods, whereas the longleaf pine , Douglas fir , and yew softwoods are much harder than several hardwoods. Softwoods are generally most used by the construction industry and are also used to produce paper pulp , and card products. In many of these applications, there

918-406: Is minimally 1 + 1 ⁄ 2 by 3 + 1 ⁄ 2 inches (38 mm × 89 mm). As previously noted, less wood is needed to produce a given finished size than when standards called for the green lumber to be the full nominal dimension. However, even the dimensions for finished lumber of a given nominal size have changed over time. In 1910, a typical finished 1-inch (25 mm) board

969-504: Is more commonly made from softwood than hardwoods, and 80% of lumber comes from softwood. In the United States and Canada, milled boards are called lumber , while timber describes standing or felled trees. In contrast, in Britain, and some other Commonwealth nations and Ireland, the term timber is used in both senses. (In the UK, the word lumber is rarely used in relation to wood and has several other meanings.) Re-manufactured lumber

1020-603: Is required. Under the prescription of the Method of Construction (營造法式) issued by the Song dynasty government in the early twelfth century, timbers were standardized to eight cross-sectional dimensions. Regardless of the actual dimensions of the timber, the ratio between width and height was maintained at 1:1.5. Units are in Song dynasty inches (31.2 mm). Timber smaller than the 8th class were called "unclassed" (等外). The width of

1071-459: Is smaller than the nominal dimensions because modern technology makes it possible to use the logs more efficiently. For example, a "2×4" board historically started out as a green, rough board actually 2 by 4 inches (51 mm × 102 mm). After drying and planing, it would be smaller by a nonstandard amount. Today, a "2×4" board starts out as something smaller than 2 inches by 4 inches and not specified by standards, and after drying and planing

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1122-422: Is still continued in some places. Otherwise, logs were sawn using a two-person whipsaw, or pit-saw, using saddleblocks to hold the log, and a pit for the pitman who worked below. In 1420 the island of Madeira  – an archipelago comprising four islands off the northwest coast of Africa and an autonomous region of Portugal – was discovered. King Henry VI sent settlers to Madeira and

1173-437: Is the result of secondary or tertiary processing of previously milled lumber. Specifically, it refers to lumber cut for industrial or wood-packaging use. Lumber is cut by ripsaw or resaw to create dimensions that are not usually processed by a primary sawmill . Re-sawing is the splitting of 1-to-12-inch (25–305 mm) hardwood or softwood lumber into two or more thinner pieces of full-length boards. For example, splitting

1224-605: Is well utilised in the construction industry. Attempts to maintain lumber quality over time have been challenged by historical changes in the timber resources of the United States – from the slow-growing virgin forests common over a century ago to the fast-growing plantations now common in today's commercial forests. Resulting declines in lumber quality have been of concern to both the lumber industry and consumers and have caused increased use of alternative construction products. Machine stress-rated and machine-evaluated lumber are readily available for end-uses where high strength

1275-517: The American Lumber Standard Committee , appointed by the U.S. Secretary of Commerce . Design values for most species and grades of visually graded structural products are determined in accordance with ASTM standards, which consider the effect of strength reducing characteristics, load duration, safety, and other influencing factors. The applicable standards are based on results of tests conducted in cooperation with

1326-728: The American colonies began in 1607 when the Jamestown settlers cut timber to build the first settlement in the new world. America's first sawmill was built at the Falls of Piscatauqua , on the line between the Province of Maine and the Province of New Hampshire , in 1634. Unauthenticated records, however, claim that as early as 1633 several mills were operating in New Netherland . The American colonies were essential to England in

1377-558: The USDA Forest Products Laboratory. Design Values for Wood Construction, which is a supplement to the ANSI/AF&;PA National Design Specification® for Wood Construction, provides these lumber design values, which are recognized by the model building codes. Canada has grading rules that maintain a standard among mills manufacturing similar woods to assure customers of uniform quality. Grades standardize

1428-404: The "quarter" system in specifications as a vogue of insider knowledge, though the materials being specified are finished lumber, thus conflating the separate systems and causing confusion. Hardwoods cut for furniture are cut in the fall and winter, after the sap has stopped running in the trees. If hardwoods are cut in the spring or summer the sap ruins the natural color of the lumber and decreases

1479-463: The 1950s. In his treatment, copper is a fungicide, arsenic is a secondary fungicide and insecticide, while chromium is a fixative which also provides ultraviolet (UV) light resistance. Recognized for the greenish tint it imparts to timber. this preservative was extremely popular for many decades until arsenic toxicity and carcinogenicity was recognized by the US EPA and other regulators. Kamesam

1530-409: The 4×4 (89 mm × 89 mm), are common lumber sizes used in modern construction. They are the basic building blocks for such common structures as balloon-frame or platform-frame housing. Dimensional lumber made from softwood is typically used for construction, while hardwood boards are more commonly used for making cabinets or furniture. Lumber's nominal dimensions are larger than

1581-828: The UK), 2×6 , and 4×4 . The length of a board is usually specified separately from the width and depth. It is thus possible to find 2×4s that are four, eight, and twelve feet in length. In Canada and the United States, the standard lengths of lumber are 6, 8, 10, 12, 14, 16, 18, 20, 22 and 24 feet (1.8, 2.4, 3.0, 3.7, 4.3, 4.9, 5.5, 6.1, 6.7 and 7.3 m). For wall framing, precut "stud" lengths are available, and are commonly used. For ceilings heights of 8, 9 or 10 feet (2.4, 2.7 or 3.0 m), studs are available in 92 + 5 ⁄ 8 inches (2.35 m), 104 + 5 ⁄ 8 inches (2.66 m), and 116 + 5 ⁄ 8 inches (2.96 m). The length of

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1632-529: The United Kingdom, Europe, Australia, and New Zealand, while in other parts of the world (mainly the United States and Canada) the term timber refers specifically to unprocessed wood fiber , such as cut logs or standing trees that have yet to be cut. Lumber may be supplied either rough- sawn , or surfaced on one or more of its faces. Rough lumber is the raw material for furniture-making, and manufacture of other items requiring cutting and shaping. It

1683-509: The United States began with the publication of the American Lumber Standard in 1924, which set specifications for lumber dimensions, grade, and moisture content; it also developed inspection and accreditation programs. These standards have changed over the years to meet the changing needs of manufacturers and distributors, with the goal of keeping lumber competitive with other construction products. Current standards are set by

1734-422: The actual standard dimensions of finished lumber. Historically, the nominal dimensions were the size of the green (not dried), rough (unfinished) boards that eventually became smaller finished lumber through drying and planing (to smooth the wood). Today, the standards specify the final finished dimensions and the mill cuts the logs to whatever size it needs to achieve those final dimensions. Typically, that rough cut

1785-402: The amount of oxygen is inadequate. Fungi lumber/timber defects: Following are the insects and molluscs which are usually responsible for the decay of timber/lumber: Softwood Softwood is wood from gymnosperm trees such as pines and spruces . Softwoods are not necessarily softer than hardwoods. The hardest hardwoods are much harder than any softwood, but in both groups there

1836-402: The conversion of log timber into planks 30 times faster than previously. The circular saw, as used in modern sawmills, was invented by an Englishman named Miller in 1777. It was not until the nineteenth century, however, that it was generally applied, and its great work belongs to that period. The first insertable teeth for this saw were invented by W. Kendal, an American, in 1826. Logging in

1887-408: The countries with significant sawmilling industries. Historical wood-frame home building regions are: Europe, North America, Japan. Different areas of the world are recognized as significant timber suppliers; however, these areas (Indonesia, Sarawak, New Guinea, etc.) are exporters of raw logs and do not have a significant domestic lumber producing industry. The largest lumber manufacturing regions in

1938-518: The formula of Wolman Salts which worked against termite damage. In addition Kamesam introduced the use of chromium to bind the two salts to the fibres of wood. He received an Indian patent in 1933, a British patent in 1934 and a US patent in 1938. The application of the ASCU process for use in the Indian Railways was examined by a committee headed by Sir C.V. Raman in 1933-34. In 1936 he designed

1989-543: The modern era; a 1st class timber during the Sui was reconstructed as 15×10 (Sui dynasty inches, or 29.4 mm). Defects occurring in lumber are grouped into the following four divisions: During the process of converting timber to commercial forms of lumber the following defects may occur: Fungi attack wood (both timber and lumber) when these conditions are all present: Wood with less than 25% moisture (dry weight basis) can remain free of decay for centuries. Similarly, wood submerged in water may not be attacked by fungi if

2040-491: The most common and widely used method of sawing logs. Plain sawn lumber is produced by making the first cut on a tangent to the circumference of the log. Each additional cut is then made parallel to the one before. This method produces the widest possible boards with the least amount of log waste. Lumber manufacturing globally is determined by the preferred style of building; areas with a "wood building culture" (homes were built from wood rather than other materials like brick) are

2091-505: The quality of lumber at different levels and are based on moisture content, size, and manufacture at the time of grading, shipping, and unloading by the buyer. The National Lumber Grades Authority (NLGA) is responsible for writing, interpreting and maintaining Canadian lumber grading rules and standards. The Canadian Lumber Standards Accreditation Board (CLSAB) monitors the quality of Canada's lumber grading and identification system. Their common grade abbrievation, CLS, Canadian Lumber Standard

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2142-672: The role of supplier of lumber for the British fleet. By the 1790s, New England was exporting 36 million feet of pine boards and at least 300 ship masts per year to the British Empire. The timber supply began to dwindle at the start of the twentieth century due to significant harvest volumes, so the logging industry was forced to seek timber elsewhere; hence, the expansion into the American West. Logs are converted into lumber by being sawn, hewn , or split . Sawing with

2193-525: The rules of the Sciages Avivés Tropicaux Africains (SATA) and is based on clear cuttings – established by the percentage of the clear surface. In North America, market practices for dimensional lumber made from hardwoods varies significantly from the regularized standardized ' dimension lumber ' sizes used for sales and specification of softwoods – hardwood boards are often sold totally rough cut, or machine planed only on

2244-501: The settlers started clearing the huge expanses of forest in order to grow crops. Felled trees were made into planks by water-powered mills and the timber (cedar and yew) was shipped to Portugal and Spain. About 1427, the first sawmill in Germany was built. Cornelis Corneliszoon (or Krelis Lootjes) was a Dutch windmill owner from Uitgeest who invented the first mechanical sawmill, which was wind-powered, on 15 December 1593. This made

2295-453: The two (broader) face sides. When hardwood boards are also supplied with planed faces, it is usually both by random widths of a specified thickness (normally matching milling of softwood dimensional lumber) and somewhat random lengths. But besides those older (traditional and normal) situations, in recent years some product lines have been widened to also market boards in standard stock sizes; these usually retail in big-box stores and using only

2346-459: The value of the wood for furniture. Engineered lumber is lumber created by a manufacturer and designed for a certain structural purpose. The main categories of engineered lumber are: In the United States, pilings are mainly cut from southern yellow pines and Douglas-fir . Treated pilings are available in chromated copper arsenate retentions of 0.60, 0.80 and 2.50 pounds per cubic foot (9.6, 12.8 and 40.0 kg/m ) if treatment

2397-424: The world are: China (18%); United States (17%); Canada (10%); Russia (9%); Germany (5%); Sweden (4%). In early periods of society, to make wood for building, the trunks of trees were split with wedges into as many and as thin pieces as possible. If it was necessary to have them still thinner, they were hewn, by some sharp instrument, on both sides, to the proper size. This simple but wasteful manner of making boards

2448-525: Was 13 ⁄ 16  in (21 mm). In 1928, that was reduced by 4%, and yet again by 4% in 1956. In 1961, at a meeting in Scottsdale, Arizona, the Committee on Grade Simplification and Standardization agreed to what is now the current U.S. standard: in part, the dressed size of a 1-inch (nominal) board was fixed at 3 ⁄ 4  inch; while the dressed size of 2 inch (nominal) lumber

2499-516: Was reduced from 1 + 5 ⁄ 8  inch to the current 1 + 1 ⁄ 2  inch. Dimensional lumber is available in green, unfinished state, and for that kind of lumber, the nominal dimensions are the actual dimensions. Individual pieces of lumber exhibit a wide range in quality and appearance with respect to knots, slope of grain, shakes and other natural characteristics. Therefore, they vary considerably in strength, utility, and value. The move to set national standards for lumber in

2550-742: Was born in Narsapur in West Godavari district of Andhra Pradesh and was a younger brother of S. V. Ramamurthy . After primary education at Visakhapatnam , he graduated from Presidency College , Chennai and obtained his B.E. from Guindy Engineering College . He also obtained an ME (honours) and became a Member of the Institution of Engineers (India). He joined in Forest Research Institute , Dehra Dun and later promoted as an Expert-in-charge of Wood Preservation. He

2601-468: Was sent to Germany for research and worked with Richard Falck (1873-1955), a specialist on fungi and their damage to wood. They developed the 'Falkamesam arsenic-copper mixture' which was patented in Poland in 1932. Until then Wolman's formulation – famously known as Wolman Salts – contained dinitrophenol , a chemical manufactured by Hicksons, UK. In 1933, Kamesam added Copper sulphate as an anti-fungal to

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