What do the numbers on a grade stamp mean?
Sturd-I-Floor grade stamp will only display one number that indicates maximum joist spacing. Sized for spacing – panels are manufactured to allow for the required 1/8” spacing along edges. An Exposure 1 Bond Classification indicates that panels will withstand normal construction delays and structural properties will not be affected.
What do the numbers on Sturd-I-floor grade stamp mean?
The first number indicates roof and wall support spacing. The second number is for floors (2 layers may be required to meet code). Sturd-I-Floor grade stamp will only display one number that indicates maximum joist spacing. Sized for spacing – panels are manufactured to allow for the required 1/8” spacing along edges.
What do the grade marks on the lumber mean?
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: WWPA certification mark - This symbol indicates that lumber bearing this trademark has been graded under the supervision of Western Wood Products Association.
What are lumber grade stamps used for?
Lumber Grade Stamps Builders, inspectors and other professionals use these grades to ensure that quality lumber is used where it is needed. Structural engineers take these grades into consideration when designing structures. Building codes widely used in the U.S. and Canada typically require graded, stamped lumber to be used in framing.
What is a span rating?
What is APA wood?
How much spacing is needed for a panel?
What is the mill number?
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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.
Why is lumber stamped?
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 information is provided by the group number in a plywood grade stamp?
How are the species of wood classified in the fabrication of plywood? 1-5 different groups according to strength and stiffness. Group 1 species have the highest strength characteristics, and Group 5 species have the lowest strength properties.
Does OSB have different grades?
Five grades of OSB are defined in EN 300 in terms of their mechanical performance and relative resistance to moisture: OSB/0 – No added formaldehyde. OSB/1 – General-purpose boards and boards for interior fitments (including furniture) for use in dry conditions. OSB/2 – Load-bearing boards for use in dry conditions.
What does the stamp on wood mean?
That's why every stick of lumber coming out of a sawmill is appraised by trained inspectors and given a grade stamp. This cryptic tattoo indicates that a piece of wood meets established standards for strength and stiffness, and it also offers useful information about the type of wood and how much moisture it contains.
What information is on a lumber grading stamp?
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. The grade of a given piece of lumber is based on its strength or appearance, or both.
How do you read a sheathing stamp?
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.
What are the 5 grades of plywood?
Typical plywood grades and characteristics“A” Grade. Sanded smooth, paintable. ... “B” Grade. Solid surface with some repairs, usually football-shaped patches and/or wood filler. ... “C” Grade. Tight knots to 1-1/2 in. ... “D” Grade. Knots and knotholes up to 2-1/2 in.
What is structural grade plywood?
Structural Plywood is suitable for structural applications as a Type A bond is used. Structural plywood comes in eight standard stress grades and five face veneer qualities. In exposed applications, structural plywood must be treated to ensure its full-service life and to minimise checking.
What does CDX mean on plywood?
What is CDX? CDX is veneer plywood, which is manufactured by gluing and pressing together sheets of wood. The letters C and D represent the grades of either side of the plywood, while X stands for exposure.
Which is stronger OSB or CDX?
OSB is made using small wood chips or wood flakes that are then glued together. On the other hand, CDX is a type of plywood that uses very long and thin wooden veneers that are oriented in a cross-grain pattern. This, therefore, means that CDX plywood is quite a bit stronger than OSB.
Which is stronger plywood or OSB?
Osb is stronger than plywood in shear. Shear values, through its thickness, are about 2 times greater than plywood. This is one of the reasons osb is used for webs of wooden I-joists. However, nail-holding ability controls performance in shear wall applications.
When did they start stamping lumber?
About the History of Lumber Grade Marking It begins in 1883 and leads us up to 1940 when SPIB was created.
Why are the ends of lumber painted?
Sealing the end-grain with paint or wax equalizes board shrinkage and avoids splits. A well-designed lumber rack is the second secret to successful wood storage.
How can you tell if lumber has been treated?
How can you tell if wood is treated? Pressure-treated lumber has end tags or stamps identifying the chemical used. It can have a green or brown color from the treating process. Treated wood can smell oily or chemical as opposed to a nice natural smell of untreated wood.
What does it mean when lumber is marked purple?
At Home Depot, lumber marked with purple paint means it's on sale. This happens when the lumber yard team culls old, ugly, or otherwise unwanted products from the floor.
OSB-4204 How to Read a Weyerhaeuser OSB Grade Stamp
Title: OSB-4204 How to Read a Weyerhaeuser OSB Grade Stamp Author: Weyerhaeuser Keywords: TB-4204 Created Date: 12/11/2018 2:10:43 PM
Plywood Grade Stamp Explained - Inspect USA Blog
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. The Exposure Durability Classification defines whether the panel should be used for interior or exterior applications: Exterior panels have a … Continue reading "Plywood Grade ...
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.
Why do builders use lumber grades?
Builders, inspectors and other professionals use these grades to ensure that quality lumber is used where it is needed.
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 D-Blaze on lumber?
Lumber that has been treated with flame-resistant chemicals may bear a "D-BLAZE" notation on its grade 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 wood?
CCA is comprised of arsenic, chromium and copper. In wood, CCA is used as a chemical preservative. CCA is also a pesticide.
What type of lumber is used for framing?
Building codes widely used in the U.S. and Canada typically require graded, stamped lumber to be used in framing.
What is panel grade?
Panel grade —The term “grade” may refer to panel grade or veneer grade. Panel grades are generally identified in terms of the veneer grade used on the face and back of the panel (e.g., A-B, B-C) or by a name suggesting the panel’s intended end use (e.g., APA Rated Sheathing, Underlayment).
What is the span rating of a sheathing panel?
Span rating —The span rating for APA RATED SHEATHING is two numbers separated by a slash. The left-hand number is the maximum recommended center-to-center spacing for supports in inches when the panel is used for roof sheathing with long dimensions across supports. The right-hand number is the maximum center-to-center spacing of supports in inches when the panel is used for subflooring with the long dimension across supports. The Span rating on APA RATED STURD-I-FLOOR underlayment and APA RATED SIDING panels appears as a single number. The Span ratings for APA RATED STURD-I-FLOOR and underlayment panels, like those for APA RATED SHEATHING, are based on application of the panel with the long dimension or strength axis across three or more supports.
What is APA in wood?
For nearly 90 years, APA – The Engineered Wood Association has focused on helping the industry create structural wood products of exceptional strength, versatility and reliability. Combining the research efforts of scientists at APA’s 42,000-square-foot Research Center with the knowledge gained from decades of field work, and cooperation with our member manufacturers, APA promotes new solutions and improved processes that benefit the entire industry. Learn more.
What is siding face grade?
Siding face grade —Grade identification of siding face, based on number of repairs and appearance characteristics.
What is performance category?
Performance Category —A panel designation related to the panel thickness range that is linked to the nominal panel thickness designations used in the International Building Code (IBC) and the International Residential Code (IRC).
What are the disadvantages of platform framing?
A disadvantage of platform framing is: lumber shrinkage causes vertical movement which can crack plaster and misalign doors and window openings. The most common type of connector between heavy timber members is: steel gusset plates with through bolts.
What causes vertical movement in a window?
lumber shrinkage causes vertical movement which can crack plaster and misalign doors and window openings.
Can laminated wood be formed?
Laminated wood can be formed into sizes and shapes that are unavailable from solid pieces cut from logs.
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 WWPA grade?
WWPA is certified as a rules writing and inspection agency by the Board of Review, American Lumber Standard Committee and is approved to provide mill supervisory services under its rules and the rules of the West Coast Lumber Inspection Bureau, the Redwood Inspection Service, the National Lumber Grades Authority for Canadian Lumber and the NGR portion of the Southern Pine Inspection Bureau Rules. In addition, WWPA is approved to supervise finger-jointed and machine stress-rated (MSR) lumber.
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 a span rating?
Span Rating – Refers to the maximum center to center support spacing when panels are installed during typical construction. The first number indicates roof and wall support spacing. The second number is for floors (2 layers may be required to meet code). Sturd-I-Floor grade stamp will only display one number that indicates maximum joist spacing.
What is APA wood?
APA is a third-party quality control association that represents US and Canadian manufacturers of structural engineered wood products.
What is the mill number on an OSB?
Mill Number, Date, and shift code– each mill in North America has a dedicated mill number that gets printed on the OSB panel along with the date and shift code. This allows the inspector to easily identify where and when the OSB board was manufactured.
How much spacing is needed for a panel?
Sized for spacing – panels are manufactured to allow for the required 1/8” spacing along edges.
What does a grade stamp on lumber mean?
That's why every stick of lumber coming out of a sawmill is appraised by trained inspectors and given a grade stamp. This cryptic tattoo indicates that a piece of wood meets established standards for strength and stiffness, and it also offers useful information about the type of wood and how much moisture it contains. Follow along as we decode the stamp and show you how to get the most lumber for your money.
What percentage of moisture is in kiln dried lumber?
You'll get less movement with kiln-dried (KD) or surface-dry (S-DRY) lumber, which has a moisture content between 16 and 19 percent.
Is Douglas Fir stronger than Hemlock?
While all species are graded at the same four levels of strength and appearance, they are not equally strong. A joist made of Douglas fir, for instance, will cover a greater span than a hemlock joist of the same size and grade. But using bigger joists of a cheaper species might save you money without loss of strength.
What is a span rating?
Span Rating – Refers to the maximum center to center support spacing when panels are installed during typical construction. The first number indicates roof and wall support spacing. The second number is for floors (2 layers may be required to meet code). Sturd-I-Floor grade stamp will only display one number that indicates maximum joist spacing.
What is APA wood?
APA is a third party quality control nonprofit trade association that represents US and Canadian manufacturers of structural engineered wood products.
How much spacing is needed for a panel?
Sized for spacing – panels are manufactured to allow for the required 1/8” spacing along edges.
What is the mill number?
Mill Number – each mill that is located in North America has a dedicated mill number, date and shift code. This allows the inspector to easily identify where and when the OSB board was manufactured.