![]() ![]() G4-4 allows most defects to an unlimited extent, as long as the piece of wood remains intact, which means that the wood can be handled without falling apart.ĭefects that may be present to an extensive but not unlimited extent are wane, checks and deformations.Ī small amount of soft rot is permitted. Grade G4-4 is suitable for low quality formwork and packaging. Note This grade is sometimes the highest to which spruce is sorted, which means that it will contain G4-3 or better. Extensive deformations are also permitted, as are knot holes. This grade allows defects that greatly affect the appearance in terms of both size and number, including decayed knots, bark-encased scars, blue stain, firm rot, through checks, wavy grain and top rupture. Grade G4-3 is suitable for applications such as lower quality decking and sheathing, plus packaging wood. Note This grade is often the highest to which spruce is sorted, which means that it will contain G4-2 or better. Blue stain, firm rot, wavy grain and top rupture are also permitted to a small extent. Grade G4-2 permits defects that affect the appearance to a greater extent, such as bark-encased scars, pitchwood and decayed knots. In addition, the grade can be used in the form of dimension planed spruce for wall studs in non-load-bearing internal walls. Grade G4-2 is also suitable for higher quality decking and sheathing. Grade G4-2 is suitable for applications such as exterior cladding with a knotty structure. Note This grade is sometimes the highest to which wood is sorted, which means that it will contain Grade G4-1 or better. Small encased knots are also permitted, but not decayed knots. Planed spruce is often this grade.ĭefects that affect the appearance to some extent, such as bark-encased scars and reaction wood, are permitted. Grade G4-1 applications include high quality interior and exterior cladding with small knots. The grade is attained primarily by the side yield of butt logs. It is very uncommon for spruce to have Grade G4-0. A few small sound and dead knots are permitted but no encased or decayed knots. High quality, where defects that affect the appearance to a large extent, are not permitted. Grade G4-0 is suitable for planed wood for interior joinery and internal mouldings. Properties that affect the function of the wood, such as deformations, are also assessed. Dead knots, for example, are judged more harshly than sound knots. The aim of the grading is, instead, to sort wood in terms of its appearance. Wood sorted in line with SS-EN 1611-1 is not intended for load-bearing structures. Table 17 Timber gradesĬommon wood products with appropriate appearance grades and wood types.ĭescription of appearance grades in line with SS-EN 1611-1 G2 entails 2-sided visual sorting and is rarely used in Sweden. A rough comparison with Grading of Sawn Timber is given in table 18, page 62. A grade can thus have the designation G4-2, which means a 4-sided visual sorting of typical construction timber, corresponding to CLASS V, Fifths, in the Grading of Sawn Timber system. The grading designations are followed by a number from 0–4 stating the quality of the wood, with 0 as the highest quality. In these cases, the grades are called G4 and G2 respectively. Standard SS-EN 1611-1Īccording to standard SS-EN 1611-1 Sawn timber – Appearance grading of softwoods, the grading may be performed on the faces and the edges or only on the faces. The other main grades are CLASS V (Fifths), CLASS VI (Sixths) and CLASS VII, which has low quality requirements. CLASS U/S is one of the main grades, comprising unspecified proportions of sub-classes OS I – OS IV. The sawn timber is sorted into seven classes, designated I–VII. It is based on the Nordic Timber Grading Rules for Pine and Spruce Sawn Timber and the European standard SS-EN 1611-1 Sawn timber – Appearance grading of softwoods. Grading of Sawn Timber is a grading regulation established in 2020. However, among timber merchants and when describing wood grades used in construction, for example in the AMA Hus and VilmaBas databases, grading mostly follows the European standard for appearance grading of softwoods, SS-EN 1611-1. The wood is shown in the dimensions: 25x100, 50x150 and 75x200 mmĪt the Swedish sawmills, the wood is usually graded using the rules on appearance grading set out in Grading of Sawn Timber. It is thus not designed to take account of the wood’s use, for example in joinery, construction or packaging. The grading of wood is a general process based on appearance. The grade is then marked on the packaging. planing or resawing, these marks may be cut away or hard to identify. This allows the graded quality to be checked along the chain from the sawmill to the retailer. It is common for each piece of wood to be stamped on the end with a shipping mark. The parameters are assessed in visual sorting, known as appearance grading. ![]()
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