Know your Lumber: The one-stop guide for you

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Choosing lumber can be a tricky business! Even when you have made up your mind about the wood species and dimension calculations have been done, there are still things to think about. Every board is different and to really have a successful finished project, time and patience are the key to get the lumber you need. Fortunately, it is not as hard as it seems. In this article, Wooderra explores the most common lumber-related questions for the understanding of our readers, so let's get to it.


1. What are the basic lumber types?

There are two kinds of basic wood to choose from: hardwoods and softwoods. Note that the names have almost nothing to do with the real hardness of the wood. Among all wood species, there are a number of common characteristics.

Hardwood: Notice those trees that lose their broad leaves in the cold months? Those are called deciduous trees, and the source of hardwood lumber. A myriad variety is known to exist; nevertheless, there are only about 200 trees, whose lumber is sufficiently pliable for wood working. Because it is typically much slower to grow to maturity, hardwood lumber is denser than softwood lumber.

It has a set of grain patterns which is visually more interesting and contributes to its popularity among many woodworkers and homeowners. As a result, exotic hardwood flooring is a big hit in the timber industry and used in refined architecture. Hardwood lumber is also the typical material in fine woodworking, pergolas, high quality furniture building, decking, and paneling.

The grain pattern and texture of the lumber are determined by the size of the microscopic pores on the hardwoods' surface. This is very similar to our skin. You might come across different terms like close grain, meaning smaller pores, and ring porous, meaning larger pores.

Trees with close grain are for example cherry or maple; while trees like ash or oak trees are ring porous. Wooderra also offers a list of types of wood for your further understanding. If you plan to delve into and excel in wood working, hardwood lumber is the way to go. The trees are grown typically around the world so access to hardwood lumber is easy.

Affiliated with Panama Teak Forestry and Timber Resources Management, Wooderra is operated in a vertically integrated system that allows us to provide you with fresh hardwood lumber directly from the wood farmers straight to your door, no matter where you are.

Softwood: Softwood lumber comes from coniferous trees, which are commonly known to be evergreen and keep their needles all year round. Softwood lumber has a closed grain, which is not significantly visible in the finished product. To a lot of homeowners, being able to see and feel the grain on the lumber speaks volume to them about the authenticity of the wood. This is why materials like composite wood are manufactured with synthetic wood grain for the purpose of imitation.

Softwoods are much faster to grow compared to hardwoods, which is one of the reasons why softwood lumber is cheaper. It has straighter grain and is beneficial for framing work, trimmings, building (rough-in and finish), construction, and exterior projects.

Cedar, spruce and pine are the most popular softwoods in the market. Softwood trees are grown in northern hemisphere. Furthermore, softwood lumber is typically a more suitable option for a DIY project because it is less dense and easier to work with but not as versatile and beneficial for resale values.


2. What are S2S and S4S lumber?

An SxS designation is determined by how many sides of the lumber have been pre-surfaced. Simply explained:

• S2S or Surfaced 2 Sides means the board has been surfaced on two sides, but the edges are left rough.

• S4S or Surfaced 4 Sides means a board is surfaced on four sides and received a rip on both edges.

• S3S boards also exist, which are the ones surfaced on three sides, but they are less common than S2S and S4S.

So which one should you choose? It depends on your preferences. First, the price of S2S and S4S is determined by the waste removed during the manufacturing process. While S2S lumber's waste is around 10-20% of the original slab, waste for S4S lumber will be typically higher.

Additionally, for some people, it is priority to be able to use the lumber as soon as it is bought. In such cases, S4S appears to be an ideal option. For those who prefer smoothing out the edges of the lumber on their own and enjoy the extra wood working activity, go for S2S lumber. This can be the ideal option for the DIY folks who have access to the right tools.

Note that availability is also important, as certain type of lumber is only available in S2S or S4S. What's important is the order of priority when you look for lumber: first, choose the type; second, choose the finish. Additional cost might be added to the bill if there is an added finished side.


3. What is pressure-treated lumber?

Produced for exterior projects only, lumber undergoes pressure treatment for ground and above ground contact. Compared to hardwoods, softwoods are more vulnerable to rotting from fungus and water. Thus, softwood lumber which contains with these elements is often put through pressure treatment, in which a preservative chemical that enhances the lumber's performance is included.

As a result, pressure-treated lumber has high resistance to rotting and insect damage. Everyday wooden objects that are made from pressure-treated lumber are often, for example, picnic tables, light posts, mailbox posts, swing sets, and so on.

The process of pressure treating a lumber is quite simple. First, wood is stacked into a sealed tank before being treated. The goal here is to open the wood's pores so think of it like a sauna for wood, though pressured sauna, and not a heated one, as all the air is vacuumed out. Then, a preservative chemical is released into the tank, and applied pressure forces it to permeate deeply into the wood's cells. After the treatment is done, woodworker remove the wood from the tank and leave it to dry. One important note is pressure-treated lumber must be dry before it can be painted. To identify lumber that has been pressure treated in a hardware store, look for the one that has slight dampness and green hue.

What's more, the way pressure-treated lumber is handled should require a bit more care than other types because many of the chemicals used in the pressure treatment are under the category of pesticides by the Environmental Protection Agency. The following tips should be considered:

• Do not burn pressure-treated lumber in your fireplace or campfire.

• Do not use pressure-treated lumber for compost or mulch.

• Protect yourself by wearing gloves while working with it and carefully washing your hands after working with the lumber to prevent any testosterone-sapping xenoestrogens from remaining on your skin.


4. What is dimensional lumber and studs?

Dimensional lumber and studs are milled on all four sides. It is the lumber that is cut based on a list of pre-defined sizes. Available in different lengths, dimensional lumber is sawn, planed, and smoothed so that it can be ready for a wide variety of uses in different wood projects and construction. All lumber can be dimensional, depending on where you buy it. The most common size is the 2x4 (two-by-four). By 2x4, it does not mean the measurement is exactly 2 inches wide and 4 inches deep but more like 1.5 inches by 3.5 inches due to the saw's thickness.

Why is this information important to you? Because understanding the measurement helps you get the lumber you need. A tree is typically cut by mills, which is then turned into lumber shortly after the tree is harvested. At this point, there is a lot of moisture in the wood piece. When a piece of lumber is cut by the mill into a 2x4, it is actually 2 inches thick by 4 inches wide. However, as the lumber naturally dries during its travel to the storage area, it shrinks; hence, the measurement changes.

Lumber in this size is understood to be nominally two inches by four inches but actually 1.5 inches by 3.5 inches. This is the reason why dimensional lumber's sizes are commonly nominal or actual.

A 2x4 board can be at any length, 8 feet, 10 feet or even 12 feet long. While dimensions refer to the depth and width, the length is not figured into the dimensions.


5. What are the different grades for hardwood lumber?

Typically, there are four hardwood lumber grades. Depending on the amount of clear surface area that a particular board has on its worst looking side, that determines the grade. A board which is long and wide and with a lot of defect-free areas on is considered of higher grade. Depending on the placement and application, lower grade lumber may be absolutely acceptable. The following list goes from highest to lowest grade.

• First and Second (FAS): The highest quality grade. An FAS board's minimum size must be 6 inches by 8 inches, and its useable material on one face must be 83%

• Select: A Select board must be at least 4 inches by 6 inches and is 83% clear of blemishes

• No.1 Common (#1 Com): Minimum board size must be 3 inches by 4 inches, and 66.6% of the board must be clear of blemishes.

• No.2 Common (#2 Com): A #2 Com board must be at least 3 inches by 4 inches and its useable material on one face must be 50%.

Different criteria are set for different hardwoods when the aforementioned grades are given. Hardwoods are graded by National Hardwood Association so you can go to their website for more details.


6. If I want to buy softwood lumber, what are the grades?

There are two categories of softwoods: appearance boards, which are the typical material for woodworking projects; and dimensional lumber, the grade of which is determined by strength. The following grades go from highest to lowest:

• C Select: Almost entirely clear of any defects and is frequently used in cabinets and interior trimming.

• D Select: Has a decent appearance, very similar to C Select, but it may contain a few dime-sized knots.

• 1 Common: Has a knotty look. The knots are small and tight, which means they won't fall out.

• 2 Common: The knots are tighter but are bigger than that in 1 Common. 2 Common lumber is employed in shelving and paneling project. Commonly suitable for general woodworking Projects.

• 3 Common: The knots are larger than that found in 2 Common. Can also be used for installing paneling and shelving, but more suited to make crates and boxes.


7. Plywood and OSB paneling

To discuss lumber, we have to mention plywood and OSB panels. They are engineered using different wood materials and by-products. Layering thin sheets of wood, called piles, makes a plywood piece. Each layer is placed 90 degrees from the layer underneath and then glued together. This construction gives plywood its strength. Plywood can be manufactured from softwood, hardwood, or even a combination of both. On the other hand, OSB or Oriented strand board is made up of flakes of wood.

Plywood is a popular material when it comes to flooring, siding, and roofing projects. Both OSB and plywood can be employed in sheathing, shelving, subfloors, and other applications.


8. What are those letters or symbols printed on the lumber?

They are called grade stamp. Next time you are out shopping for lumber or having it delivered to you, don't forget to check for a stamp, because for example, different lumber yards might have different names for the same grade. If you are having difficulty figuring it out, contact us. Remember, color consistency and grain patterns are not indicated by the grade. The following indicates the most common stamp:

• Mill's number, symbol, or name. For example, 12.

• Sign that the lumber was surfaced dried: S-DRY or S-GRN. This would show the moisture content (MC). S-DRY is 19% or less in MC and S-GRN is over 19%. More directly, some can be stamped as MC 15 meaning 15 percent or less.

• Lumber originated from a Douglas fir: D-FIR within a triangle

• Symbol of the company that provides quality control supervision. For example, WWP®

• Grade: For example, 1COM. It is often abbreviated.

• Wood species marker: Each type of tree has a symbol or abbreviation. For example, PP means Ponderosa Pine.

Understanding these little stamps help you identify the type of tree the lumber came from, its grade, its classification, its moisture content, who supervise quality control, and so on .


9. What are the common lumber defect terms?

Depending on how the tree it comes from grows or how the machining process goes in the mill, both softwood and hardwood lumber will have certain defects. Lumber defects are best to be kept to a minimum, though they can be worked with and employed in top-notch woodworking projects. Look out for the following common defects.

• Twist: Multiple bends detected in a board.

• Split: There is cracking running through the whole piece of wood, most commonly at the ends.

• Shake: Grain is separated in between the growth rings. Grain separation often goes along the board's face and sometimes beneath its surface.

• Knothole: There are two types of knot. First is a tight knot, which is usually not a big concern. Second is a loose or dead knot, which is surrounded by a dark ring. This knot may fall out.

Cup: There is a hollowness across a board's face

Crook: or aka crown, meaning along the edge line, a warp is found.

Bow: From one end to the other, a warp is detected on a board's face

Check: Crack is found along the board's annual growth ring, which does not run through the entire board's thickness.


10. What are some lumber characteristic terms?

There are some that are common in all wood species of hardwoods and softwoods. Get to know your lumber:

Color: This contributes to the wood's personality. Different colors convey different visual effects. Let's take tiger teak for example. It would definitely give you a very different vibe and character than white pine.

Density: Heavy woods like Almendro are identified with its hardness, interlocked grain, and high resistance to dents, wear, and scratches better than softwoods.

Texture: Wondering about the condition of the surface and its stability? The short way to identify these factors is the word "texture". You must know the lumber's texture when deciding how the material is finished.

Wood grain: This term has been repeated over and over throughout this article and certainly in others. The reason is that the variances in grain direction can influence your project in a significant way. Wood grain is the word used to describe the direction that the wood cell fibers grown in. How specifically is this important? For example, a straight-grained broad has typically the strongest grain direction to work on a structural application, while grain with some characteristics is more suitable for decorative projects. The density of the grain pattern also determines strength. The tip is to look for a robust piece of lumber with a tight grain pattern and ditch the loose one.

There you have it, pretty much a primer of the most typical considerations for anyone when considering lumber. Keep this guide handy so you can come back to it next time you need to examine the lumber you've just bought.

Happy lumbering!

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