What does a grade stamp on the back of a wood structural panel indicate? Their trademark grade stampidentifies each panel, lists its specifications and intended use. RATED SIDING – APA Rated Siding products include plywood, over laid oriented strand board (OSB
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What does a grade stamp on the back of a panel indicate?
What does a grade stamp on the back of a wood structural panel indicate? Intended structural application and its suitability for exposure of water What is a disadvantage of using fire-retardant treatments on wood?
What is a grade stamp on lumber?
For advertising purposes, mills pay grading agencies for the right to place a grade stamp on their lumber. When the mill subscribes, they are assigned an identification number by that grading agency. Some mills stamp their name or trademark on the lumber as well.
How do I know what grade of lumber I have?
Inspectors should not use these guidelines to guess the grade of lumber that has no visible grade stamp. There are plenty of #3 grade panels that that appear clear of all knots, and #2 grade panels may have knots, splits and generally look awful. Inspectors may also find stamps signifying that wood has been harvested sustainably.
What does the WWPA grade mark on lumber mean?
WWPA uses a set of marks to identify lumber graded under its supervision. The grade marks are stamped on the lumber and appear near the ends of the product: WWPA certification mark - This symbol indicates that lumber bearing this trademark has been graded under the supervision of Western Wood Products Association.
Why is a grade stamp placed on lumber?
Since lumber comes from a natural source, much of it has naturally occurring defects, such as large knots or splits, and these can reduce its strength. Because of these and less obvious defects, lumber that leaves a sawmill must be appraised by trained inspectors and assigned a grading stamp.
What do markings on wood mean?
Grade markings indicate the species of wood and structural design parameters. The quality of the wood supplied must be equal to or greater than that shown on the drawings and specifications or the stability of these structures will be impaired.
What does the stamp on plywood mean?
The span rating indicates the maximum inches between supports (i.e. joist, truss etc) that the panel may be applied. If there are two numbers, the first refers to roof applications, the second to floor applications.
What stamp is on treated wood?
Treated lumber is clearly stamped as such. Look for stamps that indicate ground contact levels. If it's stamped L-P22, it contains arsenic, is designed for direct contact with the ground and is the most toxic variety. If it's stamped L-P2, it's slightly less toxic and not designed for direct contact with the ground.
What are lumber grades?
Hardwood grading for lumber considers the size and number of pieces (or cuttings) which may be yielded during the creation of a hardwood product. The grading system is based, therefore, on the measurable percentage of clear wood that is defect-free for each of the grades.
What is select structural grade lumber?
Select Structural Lumber This is the highest grade of lumber, used for its strength and durability. You'll find the least number of defects in this grade of lumber. Knots are permitted in certain sizes, as long as they are sound, firm, tight, and well spaced.
How do you read plywood grade stamps?
0:211:46How to Read Plywood Grade Stamps - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd the second number is used for subflooring. For example 48 24 48 inches is the recommended CenterMoreAnd the second number is used for subflooring. For example 48 24 48 inches is the recommended Center to Center between supports. And 24 inches is for subflooring. The stamp also includes the exposure.
How do I identify framing lumber?
Reading stamps of lumber grades. Information from plans and specifications will tell you what grade lumber you need, the grade stamp on the actual lumber will tell you what you have. Grade stamps for common dimensional framing lumber contain five pieces of information.
How do you read a stamp?
3:073:56Stamp collecting for beginners: How to read an SG Stamp CatalogueYouTubeStart of suggested clipEnd of suggested clipSo we've got illustration. Number 1a next to 2d the value blue the color the price for mint theMoreSo we've got illustration. Number 1a next to 2d the value blue the color the price for mint the price for used in this case we have a used example and the corresponding sg number over here sg5.
How do you read a lumber grading stick?
2:047:00Using a Lumber Rule - YouTubeYouTubeStart of suggested clipEnd of suggested clipFeet on the other to use the lumber rule to check the thickness of your stock measure the width ofMoreFeet on the other to use the lumber rule to check the thickness of your stock measure the width of the board and find the number in the correct column.
How can you tell if timber is treated?
In most cases, figuring out whether wood has been pressure treated is pretty straightforward, Shaddy says. Older pressure-treated wood has an olive-green tint, while newer pressure-treated wood has a stamp identifying it as such, and, in some cases, an alphanumeric code providing information on the level of toxicity.
How do you tell if wood is pressure treated or not?
To tell if the wood is treated, check tags, stamps, and markings of chemicals used. Smelling can also help you know if wood is treated. Treated lumber can smell oily, while untreated wood doesn't. Treated wood also has a green or brown hue from the treatment process.
Where are grade marks on lumber?
The grade marks are stamped on the lumber and appear near the ends of the product: Most grade stamps, except those for rough lumber or heavy timbers, contain 5 basic elements:
What does grade designation mean?
Grade designation - The grade is shown by the grade name, number or abbreviation. Species - indicates species by individual or combination species name. Seasoning - The moisture content or conditioning of the piece at the time of manufacturing:
What is Western Wood Products Association?
Western Wood Products Association is one of the largest associations of lumber manufacturers in the United States, representing sawmills in the 12 western states and Alaska. The Association's Quality Assurance Division supervises lumber grading by maintaining a highly competent staff of lumber inspectors who regularly check the quality ...
What is lumber grade?
A lumber grade is the quality-control standard for lumber that has been in place since such standards were instituted in 1960, following a revision to Canadian and U.S. building codes. Lumber is graded using the American Lumber Standards, which are based on the structural integrity of a board.
What is a S-P-F stamp?
The species of lumber is stamped, and is also abbreviated. Some common examples include: "S-P-F" represents spruce-pine-fir, a common grouping for some of the Eastern softwoods.
Why is lumber considered natural?
Since lumber comes from a natural source, much of it has naturally occurring defects, such as large knots or splits, and these can reduce its strength. Because of these and less obvious defects, lumber that leaves a sawmill must be appraised by trained inspectors and assigned a grading stamp.
What is the moisture content of lumber?
Most lumber is dried to the "S-DRY" (surfaced dry) condition, meaning that that the moisture content is less than 19%.
What is CCA in construction?
CCA is comprised of arsenic, chromium and copper.
What is a D-Blaze stamp?
Lumber that has been treated with flame-resistant chemicals may bear a "D-BLAZE" notation on its grade stamp. In summary, information about the wood's quality is contained in grading stamps, which are placed on every piece of manufactured lumber.
What is the acronym for Redwood Inspection Service?
They can be identified on a stamp by the following abbreviations: Redwood Inspection Service (R1S); Northeastern Lumber Manufacturers Association (NELMA); Northern Hardwood and Pine Manufacturers Association (NHPMA); ...
Grade Stamps 101
Let's take a look at a lumber stamp in general and then look specifically at some of the stamps you'd find at Dunn Lumber.
Learn more
So, that's a quick look at grade stamps! One thing to remember is that different species will naturally reflect different strengths, for the same dimension and grade. You'll find helpful information here and here about the basic idea of "relative strength."
Do you need a grade tag for lumber?
Any lumber you purchase should have a grade stamp or end tag. These markers provide a lot of important information related to the characteristics of the wood. Each piece of lumber will be visually or mechanically inspected according to the number of defects that are present and graded accordingly to meet consistent visual and structural standards.
Can you remove a grade stamp from a deck?
Using grade stamp information will be helpful when selecting your materials, but the markings themselves act as a visual defect on the surface of a deck. You may be able to turn the board over to hide the stamp. Otherwise, the only way to remove grade stamps from lumber is to sand the board.
What is a lumber grade stamp?
Lumber is graded to provide builders, architects, building officials and other people with key information. A grade stamp tells you at least five things about the stick of lumber that it’s printed on grade, species, moisture content when surfaced, mill or manufacturer, and name of the agency that supervised the grading.
What do grade stamps look like?
They may look like Egyptian hieroglyphics or Anglo-Saxon runes, but you have to make sure the grade stamps are there if you design, build or inspect wood-frame buildings.
What is SPF lumber?
Purchase SPF (spruce-pine-fir) lumber from Canada, and you’ll get a mix of red, white, black and Englemann spruce; lodgepole and jack pine; and balsam and alpine fir. Even the singular-sounding southern pine is a species combination of loblolly, longleaf, shortleaf and slash pines.
What is redwood wood?
Names (redwood), abbreviations (D Fir for Douglas fir) or symbols (PP for Ponderosa pine) identify the kind of wood, or species, from which the lumber was sawn. Some softwoods, such as redwood and western red cedar, are identified and sold individually.
What is the moisture content of S-DRY siding?
But in “knotty” grades such as #2 common, S-DRY promises only that the moisture content of the wood didn’t exceed 19% when surfaced.
Do all lumber and wood based panels need a grade stamp?
Because building codes throughout the country require that all lumber and wood-based panels used for structural purposes bear the grade stamp of an approved grading or inspection agency .
What is span rating?
The span rating indicates the maximum inches between supports (i.e. joist, truss etc) that the panel may be applied. If there are two numbers, the first refers to roof applications, the second to floor applications.
What is exposure 1 panel?
Exposure 1 panels are designed for protected construction and industrial applications and can be exposed to the elements for a short time, but not permanently. Exposure 2 panels are intended for protected construction and industrial applications where the potential for conditions of high humidity and water leakage exist.