A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  sample board A representative piece of timber of a known moisture content that is placed in a stack, or a predryer or kiln charge, so that it may be removed for comparative examination, weighing, or testing during the drying process. santiago declaration 1995 At the sixth meeting of the Montreal Process Working Group in Santiago Chile, in February 1995, the then 10 member countries endorsed a statement of political commitment known as the 'Santiago Declaration', including a comprehensive framework of 7 criteria and 67 indicators (the Montreal Process). Argentina and Uruguay have since endorsed the Declaration. sap The fluid in green wood that contains nutrients and other chemicals in solution. sapwood Outer layers of wood which, in a growing tree, contain living cells and reserve materials such as starch. Under most conditions the sapwood is paler in colour and more susceptible to decay than heartwood. sawed veneer Veneer produced by sawing sawn timber Timber finished to size with a saw. scarf joint A joint made by bonding two matching bevelled ends or edges. scribe To mark for an irregular cut. seasoned timber Timber that has been dried so that the maximum moisture content anywhere in the piece does not exceed 15%. seasoning Drying timber to a moisture content appropriate to the conditions and purposes for which it is to be used. seasoning stresses Stresses in timber caused by variation in shrinkage as it dries. set Permanent deformation in wood that occurs during drying when the tensile and compressive stress exceeds its elastic limit. Set prevents normal shrinkage of the timber and can lead to more obvious defects such as casehardening. Compression - Set that occurs during compression, which tends to give the wood a smaller than normal dimension after drying. Compression set is usually found in the inner layers of wood during the later stages of drying, but sometimes occurs in the outer layers after extended conditioning or rewetting. Tension - Set that occurs during tension, which tends to increase the dimensions of the wood after drying. Tension set usually occurs in the outer layers of wood during drying. shake Separation or breakage of the wood fibres caused by stresses in the standing tree or by felling and handling of the log. It is not caused by shrinkage during drying. shear A condition of stress or strain where parallel planes slide relative to each other. shear connector Usually metal connectors fitted inside a timber joint to transfer shear across a wide area of grain. shear panel a selection of wall designed to resist lateral forces acting in, or parallel to, the plane of the wall sheet metal connector A shaped connector made of sheet metal and perforated so that nails can be driven through. shrinkage The reduction in dimension or volume which takes place in timber when the moisture content is reduced below fibre saturation point, expressed as a percentage of the original dimensions or volume. Linear shrinkage occurs in three directions radial, tangential and longitudinal. sill The bottom member of a door or window frame. It is usually angled to shed water. sill plate The structural member forming the bottom of a rough opening for a door or window. skillion roof a monoslope (single pitched) roof without a ridge or peak, providing the main roof or part of a roof sliced veneer Veneer that is sliced off a log or flitch with a knife. sling A unit of timber. Synonymous with pack. softwood A general term for timber of trees classified botanically as Gymnosperm. Commercial timbers of this group are nearly all conifers. The term has no reference to the relative hardness of the wood. sorting Segregation of sawn wood items into groups that have similar characteristics, such as thickness, species, grades, and grain patterns, and into classes for stacking or racking, such as width and length. sound knot A knot that is solid across its face, at least as hard as the surrounding wood, and shows no indication of decay. space frame see beam grid sparge line A steam pipe that has a series of holes in it. species A subdivion of a genus in the classification of plants. Species of plants are distinguished by the characteristics of fruits,flowers, leaves, bark and wood. specific gravity The ratio of the density of wood to the density of water at 4 C. Specific gravity of wood is usually based on green volume and oven-dry weight, in which case it is known as basic specific gravity. See also basic density. splice To join the ends of timber elements together. split A defect that occurs when tensile stresses cause the wood fibres to separate and form cracks. Splits are cracks that extend through a piece. spring A longitudinal curvature of the edge of a piece of timber, not affecting the face. springing Support point or origin. stack A number or racks positioned one above the other and separated by bearers or gluts. Top - Any cover that protects or restrains the top rows of boards of a stack Weight - A stack top that significantly restrains the timber in the top racks of the stack. They are often a piece of flat steel or a pre-cast concrete slab the same width and length as the rack. stain A discoloration in wood that may be caused by microorganisms, metal, or chemicals. The term also applies to materials used to impart colors to wood. Blue –A bluish or grayish discoloration in the sapwood caused by the growth of certain dark-colored fungi. Sap - A discoloration in the sapwood caused by the growth of fungi. Sapstain is often blue but can also be red, purple and other colours. statement of forest principles This is a non-legally binding statement that reflects a first global consensus on forests. The principles are intended to apply to all types of forests, both natural and planted, in all geographical regions and climatic zones. The principles cover the entire range of environmental and development issues and opportunities including the right to sustainable socio-economic development of forest, the promotion of non-wood values of the forests and the rights of indigenous peoples and their involvement, along with other groups, in dealing with forests. steam The gaseous form of water at or above the boiling point. Saturated - Steam at 100°C and atmospheric pressure. steaming treatment A treatment sometimes carried out before commencing a drying schedule. The timber is subjected to live steam. See also reconditioning. sticker Synonymous with rack stick. Alignment - The placement of rack sticks in a rack of timber or other wood products so that they form vertical tiers. Mark - Indentation or compression of the timber or other wood product by the rack stick when the load above is too great for the bearing area. Sticker marks or sticker stain also refers to light areas under the rack stick that form as the rest of the timber darkens. stiffener All elements used to support or stiffen the slender webs of box and I-shaped beams and to enhance compressive capability of webs at support points or points of high transverse loads. stitch bolt A long bolt through laminated timber that holds the laminations together. straight grained Timber in which the fibres run parallel to the axis of a piece. strength The ability of a member to sustain stress without failure. strength group Species of timber are classified into groups according to mechanical properties of the wood of that species and AS 2878, Timbers - Classification into Strength Group. There are seven strength groups for unseasoned timber (S1 the strongest to S7 the weakest) and eight for seasoned timber (SD 1 the strongest to SD 8 the weakest). stringer 1. A beam that joins the top of columns and supports the cross members in floors and ceilings. 2. An inclined member that supports the treads of a stair. 3. A deck element in timber bridges that supports transverse deck planks and runs parallel to the beam span. structural timber Timber to be used in construction where its strength is the controlling element in its selection and use. strut A structural timber resisting compressive forces along the grain. stud One of a series of vertical framing timbers used as a supporting element in a wall or partition. super heat The heat in steam in excess of the amount of heat in saturated steam at a given pressure. sway bracing Bracing members required to resists the transverse movement of a structural element. swelling An increase in the dimensions of wood resulting from an increase in moisture content. Swelling occurs tangentially, radially, and, to a lesser extent, longitudinally. swirl figure A figure caused by irregular grain in the region of the knot. Projects | Technical Support | Environment | Education | Research | Glossary | Publication Copyright © Contact Us Feedback About