Real Specifications determine: quality requirements for lumber and furniture panels for valuable wood species, used in the trade turnover of the ORIS TRADE company.
Requirements for grade AA (grade 0).
- It is allowed to have two one-sided healthy light knots with a diameter of no more than 7 mm per face of the board (but not more than one per linear meter).
- "Eyes" (live light knots "in color" no more than 2 mm in diameter, except for "cat's paw" and group knots) are not taken into account.
- Sapwood “for processing” is allowed - edge gripping no more than 7 mm.
Requirements for grade AB (grade 1).
- UPPER PLATE
- requirements as for grade AA (grade 0).
- BOTTOM PLATE
- One-sided blind healthy knots up to 12 mm in diameter are allowed, no more than two on one face of the board.
- Eyes (live light knots "in color" no more than 5 mm in diameter) except for group ones ("cat's paw") without restrictions.
- Sapwood without restrictions
QUALITY REQUIREMENTS FOR BEECH TIMBER
Requirements for grade "AA"
- UPPER PLATE and LOWER PLATE (variety-determining defects):
- Presence of one mineral inclusion up to 7 mm per linear meter
- Capturing a false core is NOT ALLOWED.
Requirements for grade "AB"
- UPPER PLATE
- Same as AA grade
- BOTTOM PLATE
- False kernel allowed without restrictions
- No more than 3 live knots with a diameter of no more than 10 mm per face are allowed
- Dead and rotten edge, edge and end knots are allowed “for processing” (for trimming or trimming - at the end or on the edge of the board)
- Mineral inclusions up to 10 mm are allowed, 1 piece per linear meter
Requirements for grade "SS"
- UPPER PLATE and LOWER PLATE (variety-determining defects):
- requirements for grade B plastic
- NOT ALLOWED in all classes
- core, rot in all types (tobacco, etc.), rotten falling out knots, wormholes
- mushroom stains (blue and colored sapwood stains), stains from gaskets
- For beech boards, the following variety-forming characteristics are additionally distinguished:
- steamed beech - lumber that has undergone special processing ("steaming") and has a specific reddish color (the degree of color can vary from "pink" to "red" depending on the degree of steaming).
- unsteamed beech - lumber that has not undergone special treatment (“steaming”) and has a natural color characteristic of beech lumber (white).
QUALITY REQUIREMENTS FOR ASH TIMBER
Requirements for grade "AA"
- UPPER PLATE and LOWER PLATE (variety-determining defects):
- The presence of one one-sided live knot with a diameter of no more than 7 mm on one face
- Capturing the core is NOT ALLOWED.
Requirements for grade "AB"
- UPPER PLATE
- Same as AA grade
- BOTTOM PLATE
- One-sided blind healthy knots up to 12 mm in diameter are allowed, no more than two on one face of the board.
- Dead and rotten edge, edge and end knots are allowed “for processing” (for trimming or trimming - at the end or on the edge of the board)
Requirements for grade "SS"
- UPPER PLATE and LOWER PLATE (variety-determining defects):
- Unlimited kernel allowed
- No more than 2 live knots with a diameter of no more than 10 mm per face are allowed
- Dead and rotten edge, edge and end knots are allowed “for processing” (for trimming or trimming - at the end or on the edge of the board)
- NOT ALLOWED in all classes
- core, rot in all types (tobacco, etc.), rotten falling out knots, wormholes
- mushroom stains (blue and colored sapwood stains), stains from gaskets
Quality requirements for furniture panels
Determination of quality (grade):
- For all types of furniture panels:
- humidity no more than 8%+/-2%;
- dead (black) knots are not allowed;
- lamella width 40-50mm
- PVA glue D-4 (KLEIBERIT);
- grinding at least 120 units;
- thickness tolerance +0.1mm; width tolerance +/-1mm;
- packaging in shrink film.
Requirements for oak panels
- AA – Both layers are clean, without sapwood (protein). Knots of no more than 2 mm in diameter, not through, “live”, no more than 1 piece per linear meter are allowed on one face. Both faces are selected according to texture (radial and tangential cut lamellas are glued into different panels) and color (absence of sharp color transitions on one face )
- AB – The top face is clean, without sapwood, without knots. The lower (2nd face) allows the presence of sapwood (squirrel) without restrictions, as well as live knots in color with a diameter of no more than 20 mm. One face (front) is color matched (no sharp color transitions on one face)
- SS On both faces, sapwood is allowed without restrictions, live knots up to 20 mm in diameter. Rotten knots and rot are not allowed. Selection by color and texture is not carried out
Requirements for beech panels
- AA – Both layers are clean, without entrapment of the false nucleus. Knots of no more than 2 mm in diameter, not through, “live”, no more than 1 piece per linear meter are allowed on one face. Mineral inclusions are allowed up to 7 mm. Both layers are selected according to texture (radial and tangential cut lamellas are glued into different panels) and color (no sharp color transitions on one layer)
- AB – The upper layer is clean, without capturing the false nucleus. On the upper (front) face, knots are allowed no more than 2 mm in diameter, not through, “live” no more than 1 piece per linear meter. Mineral inclusions are allowed up to 7 mm. The lower (2nd face) false core is allowed without restrictions, as well as live knots “in color” with a diameter of no more than 20 mm, mineral inclusions up to 15 mm. One face (front) is selected according to color (no sharp color transitions on one face)
- SS On both faces it is allowed to capture a false core without restrictions, live knots up to 20 mm in diameter, mineral inclusions up to 15 mm. Rotten knots and rot are not allowed. Selection based on color and texture is not carried out.
All photos from the article
An assortment is understood as a set of types and standard sizes of a particular type of product, that is, as far as boards are concerned, the most important criteria are the grade and size range. It is by these factors that all products of this type are divided; we will consider the basic information that every developer who selects lumber from the group under consideration should know.
Types of products
As for the main types of products shown in the diagram above, the following can be said about each of them:
| Unedged board | This option is distinguished by the fact that only two sides are cut off and the ends are not processed. Such elements are most often used for lathing and other structures where appearance is not particularly important; the main advantage of this solution is its affordable price, which is why it is the most affordable |
| Semi-edged board | This type of product most often has two sides and one of the ends processed, but there may be bevels and bark residues on the edges. In general, this solution is of higher quality, but nevertheless it also cannot be used on visible structures where aesthetic appeal is important |
| Edged board | Most quality look products in which all sides are processed, so the geometric parameters of the elements are the same, and the strength indicators are much higher. This group of products is used most often and is in demand among developers much more than other types |
Important! According to scientific definition, a board is a type of lumber, the thickness of which does not exceed 100 m, and the width is at least twice as thick as the thickness. Elements up to 32 mm thick in hardwood and up to 40 mm in coniferous species ah refer to a thin board, the remaining options refer to a thick board.
Main design parameters
Assortment wooden planks includes requirements for grade and size, we will consider the first criterion in more detail in the next section, and in the table below we indicate the generally accepted sizes of elements:
As for the length, the generally accepted options vary from 1 to 6 meters; upon agreement, other standard sizes can be produced
Product grade
The grade of edged board directly depends on the quality of the element and its strength characteristics, this parameter is applicable only to edged elements and is intended to simplify the selection of a specific type of product for certain jobs, we will consider the main options, and the photo below shows all the defects that must be taken into account when determining the variety.
The correct choice of the type of edged board or edged beam has a great influence not only on the quality of the final product, but also on its final price.
Legal basis
Currently, the criteria and indicators of lumber quality are regulated by current state standards and take into account several factors:
In one article, we decided to briefly combine all the characteristics of lumber - this is what is important to understand and necessary for an ordinary consumer to know. We will talk about the main factors and criteria affecting grade, as well as methods for their visual determination. Our methodology is based on the above state standards and is as close as possible to the concepts of lumber grade existing on the market today. Yes, indeed, some norms state standards, adopted in the 80s, today differ from the actual properties of lumber offered for sale on the market. The main thing remains the fact that, in essence, lumber has not changed in its physical properties: pine and spruce are out of politics, despite the fact that years have passed since the adoption of GOSTs, and they can and should be used in general construction activities with confidence and without fear. Currently, to determine the grade of coniferous wood, the market has its own unwritten standards, and for most of the regulated parameters they differ from the generally accepted GOST standards. Also, deviations from GOST can be according to the classification of natural defects, taking into account their biological features, this means knots - the shape and their number, the size of the wane part. Be sure to read the article Classification of wood defects, you will find out what is an important and unacceptable defect, and what is not important. Don't be fooled when buying lumber.
General technical requirements
Softwood lumber is made from spruce, fir, pine, cedar and larch. The most common and affordable is pine or spruce lumber. Typically, for making edged lumber, raw round timber is not sorted and spruce and pine are offered for sale in a mixed form, since they also grow together in the forest. Sorting is not economically profitable - in other words, sorting will lead to an increase in the final cost of the material, but it is important to understand: the quality of boards made of pine and spruce is the same technical characteristics. That is, you can ignore this aspect - their physical characteristics are very similar, and for solving most construction problems, the quality and strength characteristics of spruce and pine will be identical.
According to the quality of structure and quality of processing, edged boards can be of five grades. There are four grades of softwood edged timber. The relative humidity of selected and 1-3 grade lumber cannot exceed 22%; by agreement with the customer, the indicators may change. The fourth grade has no restrictions on humidity. The grading is assessed taking into account the condition of the edge or face; only the worst part is taken into account when measuring. The surface roughness for selected and 1-3 grades should be less than 1250 microns; the fourth grade has no restrictions on this parameter. This is exactly what is very important. Often, cheaper lumber is sold under the guise of higher-grade lumber.
Edged timber, size according to GOST
The grade of lumber is also influenced by the criterion for limiting the natural defects of wood; we will talk about the general approaches of the standard to determining the class of wood. On our website there are many articles explaining highly professional terms and techniques that mean nothing to the average person. But even after studying the materials, experience is necessary; it is difficult for the average person to distinguish dozens of types of knots and irregularities in the structure of wood “by eye.” Most The best way To avoid being a victim of fraud is to buy edged boards or edged beams, relying on a trusted supplier. Our company "Elka-Palka" is always ready to help you. We approach the issue of sorting honestly. Let us briefly consider the main differences between the varieties of edged boards and edged timber. The criteria by which it is worth distinguishing the types and quality of boards and timber are the presence of defects or defects.
Norms and restrictions of natural vices
- Selected variety. Healthy fused knots, seam, edge, edge and partially fused knots are allowed, the number is indicated in the standard tables. The presence of rotten and shriveled branches is prohibited. End cracks (deep and shallow) can be no more than 10% and 16%, respectively. All signs of fungal diseases of wood are prohibited; warping and non-parallelism of edges is set within 0.2-1.0%.
- The board is first grade. This lumber is correct geometric shape, with dimensional tolerances within the framework of GOST. If we compare it with a selected variety, the following indicators will change slightly: the number of healthy knots increases various types, by about 10%, the number of shallow end cracks can reach 25%. Roll is allowed no more than 20% of the surface area of the material. Fungal heart stains (strips), sapwood mushroom stains and mold are allowed in a total area of the lumber area - no more than 10%. Rot is not allowed. These indicators are typical for summer period and do not affect the quality of lumber in any way, since they are natural and do not lead to destruction of the wood structure. To understand this, look at the article Wood Defects on our website. Wane is allowed blunt, on edges and facets measuring in fractions of the width of the corresponding sides of edged lumber without length restrictions, no more than 1/6. This type of wane is also called “pencil” wane. Grade 1 edged boards are mainly used for general construction work - installation rafter systems roofs, bearing structures, house construction, interfloor beams and ceilings, rough hemming and rough floors, fences.
- The board is second grade. The advantage is mainly low price. The main differences from grade 1 lumber are that the products may have larger fiber inclination values, the presence of resin pockets. The lumber may have more but minor fungal staining and small spots of bluish color. Significant wane is allowed. The main use of edged boards of the second grade is use in construction, in the manufacture of formwork, lathing on pitched roofs, it is also used for making scaffolding.
- Third grade. Significant heeling is allowed, the presence of resin pockets, can increase up to 4 pcs./m. etc., double core is allowed. Sprouting can only be one-sided; the number of core spots can increase up to 20%. A wormhole is allowed in any area. Rotten rotten and tobacco knots are allowed in the total number of partially fused and unfused healthy knots of the same size and no more than half of their number. Face and through cracks are allowed, including those extending to the end. Due to the above listed symptoms physical properties wood deteriorate sharply and it is possible to use such material in limited use- construction of temporary buildings or sheds, production of containers and pallets.
- Fourth grade. Wormholes up to 6 pcs/m are allowed. etc., rot can only be variegated sieve, the total area of rot is no more than 10% of the area of lumber. It may have a blunt and sharp wane, transverse and longitudinal warping along the face and edge, including winging.
These are the “scientific” characteristics of lumber depending on their class. Now we consider it necessary to give you practical advice, with the help of which lumber should be selected; for this you do not need to study the provisions of state standards
We deeply doubt that the majority of buyers, before purchasing lumber, measure various defects and compare their appearance with an album of diseases and defects of wood. It is for them that we will give several simple and understandable criteria for choosing high-quality wood.
- The more annual rings are visible in a vertical section and the closer they are located to each other, the more better quality lumber. If there are a lot of rings, radial sawing was performed, and these are the highest quality boards. The closer the rings are to each other, the smaller the annual growth of wood, the stronger it is, the better it resists moisture, etc. This indicator largely depends on the climatic zone of the tree’s growth; the colder the climate, the better the tree.
One more thing. It is very common to see the difference in wood quality different varieties Even professionals cannot; these assessments are quite subjective. No one spends hours examining each board. And in terms of price, the difference between them is significant. What are we getting at? Buy lumber from a trusted supplier and there will be no unpleasant “surprises”. The Elka-Palka company always has edged timber And edged board best quality, which you can buy in one call. Such a purchase will allow you to get the desired result without overpaying and without wasting extra time. Buy edged board can be inexpensive and excellent appearance, with remarkable properties.
