What are the four grades of lumber?
Table 2: Lumber Grades for Common (nonstress-graded) LumberGradeDesignationTypical UsesNo. 1ConstructionSiding, shelving, panelingNo. 2StandardSimilar uses to No. 1No. 3UtilitySheathing, subflooring, crate constructionNo. 4EconomySheathing, subflooring, creation of forms for concrete work1 more row
What is the best grade of lumber?
Hardwood grades are: FAS (First and Second) is the highest grade of hardwood lumber. It's usually 6-inches x 8-inches and is 83 percent defect-free on its best side. Select is 4-inches x 6-inches and 83 percent defect free on its best side.
What are the three grades of lumber?
There are three broad classifications of softwood lumber: Yard, Structural, and Shop and Factory. Let's take a look at each of them in detail. Lumber intended for ordinary construction and building purposes.
Are there different grades of lumber?
Lumber is graded based on the quality and appearance of the wood. These depend on various factors like the type of wood used and the number and types of defects, if any. Before we get into the different grades of lumber, let's take a look at the various defects you may find in a piece of lumber.
What kind of wood is Lowes top choice?
Top Choice | Lumber & CompositesPlywood.Dimensional Lumber.OSB.Lattice.Studs.MDF.
What is the strongest wood?
Generally acknowledged as the hardest wood, lignum vitae (Guaiacum sanctum and Guaiacum officinale) measures in at 4,500 pounds-force (lbf) on the Janka scale.
What is ABCD wood grade?
ABCD Grade: Natural wood grain and slight manufacturing imperfections allowed.
What is the best grade of hardwood lumber?
FAS: (first and second grade) This stands for the highest grade of lumber. FAS grade includes some defects but is considered the premier lumber for furniture and cabinet making. #1 & #2 common: These two grades will have a fair amount of allowable defects and color variations.
What are the C grades of timber?
C16 and C24 refer to the strength grade of a piece of carcassing timber. There are 12 strength grades as set by the British Standard in the BS 5268, but the most commonly specified are C16 and C24. Both grades are used in structural applications and are suited to different loads.
What is the cheapest wood?
Pound for pound, the cheapest wood to buy is maple. Poplar, Alder, white oak and beech are also quite inexpensive. Maple, specifically, is one of the most common woods among entry-level woodworkers and general-purpose woodworks because of its affordability and availability.
What type of wood is best for framing a house?
hardwood – softwoods such as pine, spruce or douglas fir are flexible and have straighter grain than hardwoods, giving them a leg up in strength and making them a popular choice for framing.
What is the difference between #1 and #2 treated lumber?
The main difference between #1 and #2 is the slope of the wood grain, size, spacing, and the number of knots and holes, and the length of any splits. Construction grade is #1 and Standard is #2. Both can be used for load-bearing purposes or other outdoor applications.
How is lumber graded?
Lumber is graded based on the quality and appearance of the wood. These depend on various factors like the type of wood used and the number and types of defects, if any. Before we get into the different grades of lumber, let’s take a look at the various defects you may find in a piece of lumber.
What is standard grade lumber?
Standard grade lumber is used for light framing projects. Knots in this grade of wood are not restricted regarding quality.
How are the grades of lumber determined?
As stated above, the various grades of lumber are determined by the appearance of the wood and the number of defects. These grades are determined by the U.S. Department of Commerce and the American Lumber Standards Committee. With that in mind, here is your guide to the various grades of lumber, listed from the highest grade to the lowest.
What is a knot in wood?
Knot: A knot is a naturally-occurring defect in a piece of wood. Knots are circular imperfections caused by a broken-off tree branch. Tight knots are nothing to worry about, but dead or loose knots may fall out or leave a hole. Shake: A shake is when the grain between the wood’s growth rings separates.
What are the defects in lumber?
Common Lumber Defects. Lumber defects can give a unique character to a piece of wood, but for structural integrity, the defects should be kept to a minimum. Most of the following are caused by problems with cutting, stacking, or drying the wood—with the exception of naturally-occurring knots. Bow: A bow is a curve on the face ...
What is construction grade lumber?
Construction grade lumber is used for light framing. Knots must be sound, firm, encased, and tight. There are limits on most of the defects, with the exception of some occurring only on the surface.
What is a shake in wood?
Shake: A shake is when the grain between the wood’s growth rings separates. Shakes can occur on the face of a board or below the surface.
What is the highest grade of appearance lumber?
With appearance lumber, there is additional emphasis on the physical look of the lumber given that it may be exposed once installed, e.g. used to make softwood furniture. The highest grade of appearance lumber is designated as finish, followed by selects and common. There is some variation in these terms and grades depending on the agency responsible.
What is stress graded lumber?
Softwoods that are stress-graded are used as beams, posts, studs, rafters, and joists, for example, where the material is functioning in a load-bearing capacity and working stresses will be applied. The stress gradings may be determined either by visual means or through mechanical testing according to ASTM standards and procedures, establishing standard working values for mechanical properties such as the modulus of elasticity and the bending moment. These pieces are referred to as structural lumber.
What is softwood lumber used for?
The majority use case for softwood lumber is for what is characterized as construction lumber, which may be further subdivided into stress-graded, nonstress-graded, and appearance lumber. Appearance lumber is judged mainly by the overall visual quality, whereas stress-graded or nonstress-graded lumber is more concerned with the structural integrity of the wood. Retail lumberyards typically sell nonstress-graded and appearance lumber, which is collectively referred to as “yard lumber”. Grading is done after the drying and surfacing operations are completed and is accomplished based on both the size and number of defects appearing on the better side of the piece.
Which is lighter, hardwood or softwood?
These trees are ones which usually have needles and cones as opposed to leaves. Softwood lumber tends to be lighter and has a lower density than hardwood, owing from the fact that these trees that exhibit a higher rate of growth than hardwood trees.
What is the best wood for framing?
Some of the most commonly used softwoods that are created into lumber include: Cedar – both red and yellow most commonly. Fir – often called Douglas Fir. Pine.
What is lumber made of?
Lumber is a wood product, sawn and shaped from timbers of harvested trees. By its nature, wood is not of uniform consistency and therefore will contain defects that impact the appearance of the lumber that is created from the wood material, and which may impact the structural characteristics as well.
What is yard lumber?
Retail lumberyards typically sell nonstress-graded and appearance lumber, which is collectively referred to as “yard lumber”. Grading is done after the drying and surfacing operations are completed and is accomplished based on both the size and number of defects appearing on the better side of the piece.
What is grade A plywood?
In brief, Grade A means the surface is blemish- free; Grade B may have plugged knotholes; Grade C may have small knotholes and splits (checks). Relatively larger knotholes are permitted in Grade D. Plywood is sold in a variety of thicknesses, commonly from a quarter to three-quarters of an inch.
What is pressure treated lumber?
This is regular lumber that has been injected or soaked in chemicals to prevent decay and rot.
What is the difference between plywood and sheathing?
Many varieties of plywood are sold. Finish plywood has at least one quality surface, while sheathing plywood, intended for use beneath siding, has rougher surfaces.
How many levels of lumber are there in white pine?
Lumber grading is tricky and often counterintuitive. The grading system for white pine alone consists of about ten levels. If you are going to work with wood professionally, I’d suggest you consult a basic reference work on wood and master some of the subtleties. But most of us need to know only a couple of basic facts.
How thick is 2 by 3 lumber?
Standard dimension lumber, as well as pressure-treated stock, is sold in a wide array of two-inch pieces (the dimensions refer to sizes before planing, so nominal two-by stock is actually one and a half inches thick). Two-by-threes, fours, sixes, eights, tens, and 12s are standard (actual widths: three and a half, five and a half, seven and a quarter, nine and a quarter, and eleven and a quarter inches). Common lengths are eight, ten, 12, 14, 16, 20, and 24 feet. Four-inch thicknesses are also sold in some widths.
Is fir lumber stronger than spruce?
You’ll also find when you move into larger stock that fir, for example, is much stronger (and more expensive) than spruce or pine, but better suited to wider spans for floor joists or longer rafters. When building outdoor or damp-area structures, pressure-treated lumber is another choice.
What Is Lumber Grading?
Lumber grades are a standardized way to judge the quality of a wood or piece of lumber. Both softwood and hardwood have separate grading scales. Softwood specifically has a larger variety of grading options depending on the intended application for the lumber.
What is softwood grade?
Softwood lumber grades are divided into categories based on the lumber’s use. Since softwood is so versatile, it can be used for almost everything from supporting and framing a house to paneling it. Having different categories of softwood lumber grades helps make it easier to pick the correct grade for your application, ensuring the proper strength and quality of your build.
What is appearance lumber?
Appearance lumber is any softwood lumber that’s used in applications where it will be seen, such as furniture building. As such, the appearance of the wood is important. It is divided into two categories: Select and Common, each of which can be broken down into their own specific grades.
What is non stressed lumber?
This first category of softwood lumber is primarily considered in building, for applications that don’t require a great deal of structural support, but that also aren’t highly visible.
Why is hardwood more durable than softwood?
Since hardwood forms more slowly than soft wood, it has a higher density, making hardwood lumber stronger and more durable. For this reason, hardwood is most commonly used in construction applications where longevity and appearance are both major factors, like flooring, cabinetry, furniture making, and more.
What is stress graded lumber?
Stress-graded softwood lumber is any lumber that has been graded to support weight. Stress-graded lumber is assessed by its load-bearing capacity and is primarily used for building applications that are non-visible and structurally vital, like beams, posts, studs, rafters, and joists.
Why is it important to grade wood?
Lumber grades are important because they tell you what you can expect from the quality of the wood, and how you can use each piece of wood for safe, secure construction.
What is standard grade lumber?
Standard grade lumber is used for light framing projects. Knots in this grade of wood are not restricted regarding quality.
What is construction grade lumber?
Construction grade lumber is used for light framing. Knots must be sound, firm, encased, and tight. There are limits on most of the defects, with the exception of some occurring only on the surface.
How are the grades of lumber determined?
The various grades of lumber are determined by the strength of the wood, appearance of the wood and the number of defects. These grades are determined by the U.S. Department of Commerce and the American Lumber Standards Committee.
What is the most common grade of lumber for framing?
No. 2 lumber is the most common grade for framing. Lumber of this grade contains few defects, but knots are allowed of any quality as long as they are well spaced and do not exceed the size regulations.
Is lumber a stud?
Lumber of this grade has strength and stiffness values that make it suitable for use as a vertical member of a wall. In other words, a stud. There are varying levels of quality within this grade regarding appearance.
What is grading lumber?
Worldwide, hardwood lumber producers “grade” their lumber, assuring downstream consumers of the lumber of the lumber’s quality for the intended use . Put simply, lumber grading serves quality assurance needs.
What is the lowest grade of lumber?
Several assessments lead inspectors to grade lumber according to certain categories. There are eight hardwood lumber grades in widespread use at this time. FAS is the highest and No 3B Common is the lowest grade.
What is the difference between 1 face and 1 select grade lumber?
Often, Select grade lumber is used in the Northern U.S., while 1-Face is used in the South. No. 1 Common is the standard furniture grade lumber and provides a good selection of long, medium and short cuttings at a reasonable price.
How to grade hardwood?
A very simplified, condensed overview of the steps for grading a piece of hardwood lumber is as follows: Determine the species. Some species must be processed according to special rules. Determine the surface measurement (SM).
What is 3B graded on?
No. 3B Common is graded on the basis of sound cuttings rather than clear cuttings. It is widely used for pallets and crates.
How to determine cutting yield?
Determine the cutting yield required by multiplying the surface measurement (SM) by the grade values respectively. The required yield is expressed in cutting units. A cutting unit is 1 inch wide by 1 foot long.
Is sawn wood a natural material?
“Wood is a natural material and by its very nature may contain different characteristics and defects that need to be understood and allowed for in any given application. The grading of sawn wood into categories as it is processed helps to determine to a large extent the value and potential use possible for each board of sawn lumber.”
Which grade of lumber has the same structural properties as #1?
Prime grade lumber provides the same structural properties as #1 grade lumber, but has fewer knots and better appearance
What is the minimum grain slope?
Grain slope must meet a minimum 1/8-grain slope (the less deviation from straight grain parallel to the edge, the stronger the piece of lumber).
Is treated wood wet?
Treated wood is typically still wet when it’s delivered to the lumberyard or job site. As it dries, you should expect slight changes in width and length.
Can you order non-stocked lumber?
Most lumber and building materials dealers stock only a few grades of lumber but usually allow customers to special-order non-stocked grades of lumber.
What Different Types of Lumber Grades Mean
Softwood Versus Hardwood
Softwood Lumber Grades
- The American Lumber Standard Committee (http://www.alsc.org) serves as the body that developed and maintains the American Softwood Lumber Standard PS 20 under auspices of the U.S. Department of Commerce. The majority use case for softwood lumber is for what is characterized as construction lumber, which may be further subdivided into stress-graded, nons…
Hardwood Lumber Grades
- Grading of hardwoods is significantly less complicated than that of softwoods. The American Hardwood Export Council (https://www.ahec.org/) has developed The Illustrated Guide to American Hardwood Lumber Grades which provides the basis for the grading system, measurement standards, and descriptions of the characteristics and defects associated with th…
Useful Nomenclature
- There are specific terms and definitions that are used in the grading of lumber, a few of which are summarized here for convenience: Board foot– defined as the product of the width of the board by the thickness (both in inches) multiplied by the length of the board in feet. Surface measure– defined as a measure of the surface area of the board. Sur...
Summary
- This article presented a summary of the different grading systems for softwoods and hardwoods. To learn more about the suppliers of lumber, see our guide to lumber suppliers in the U.S. To explore other topics, consult our additional guides or visit the Thomas Supplier Discovery Platformto locate potential sources of supply or view details on specific products.