The Trades

Research, insights and advice from craftsmen and industry experts

Dimensional Lumber: Types, Sizes, History

The construction of buildings today would be significantly more challenging without standardized materials. If every pipe fitting, window pane, and HVAC system had to be custom designed, the time and labor involved in building even a modest bungalow would be prohibitively expensive. 

 

Standardization—the production of materials following uniform, industry-wide dimensions—has been crucial in allowing architects and builders to construct our modern cities, suburbs, and towns. Wood was among the first materials to undergo this process of standardization. Large timbers were transformed into a material used to build the structures of most American houses:  dimensional lumber.

 

What is dimensional lumber?

Dimensional lumber is cut and finished lumber (planed on all four sides) that comes in standardized sizes. These lumber sizes are typically described in inches in the United States and in millimeters in most other countries. The two numbers used to...

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What Is the World's Strongest Wood? Top 5 Strongest Woods

In order to find the right wood for each type of construction project, builders refer to the strength of a wood.  Different woods, classified into hardwoods and softwoods, are good for different types of projects. 

Wood strength is not given in a single measurement. It is expressed using a number of measures, such as its density (the weight per a given volume); its compressive strength (or how great a weight a load of wood can bear parallel to the grain before it ruptures); its bending strength (a load of wood perpendicular to the grain); and its hardness. 

The strength of wood fiber is very consistent across all tree species, and the strength of the wood is dependent on how many fibers are packed into a given area.  Because of this fact, a wood’s density correlates very closely to its strength and hardness.  In other words, if you know a wood’s comparative density, you can get a good approximation of its hardness and strength.  

You...

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Wood Density Explained, Plus Wood Density Chart

For thousands of years, wood has been used for construction, and for making tools, weapons, and furniture. Most simply described, wood is the structural tissue found in the stems and roots of trees. And as you can imagine, not every wood is the same. Some types of wood are more suitable for construction than others, depending on their physical properties—which include density, texture, strength, hardness, stiffness, moisture content, potential for shrinkage, deformation, splitting, and flammability. 

There are two primary types of wood—hardwood and softwood—and both are used in different types of construction projects. The basic difference between the two classifications is not in their actual hardness. Hardwood and softwood are distinguished in terms of their reproduction: hardwood comes from deciduous trees, which produces seeds with a covering (think walnut, maple and oak); while softwood comes from gymnosperm trees, which have needles and produce cones...

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Pressure Treated Wood: Benefits, Uses, Types, Grades

Wood is a plentiful, renewable resource and one that construction crews know well. It can also, however, be difficult to maintain, especially when it is exposed to the elements.

“An option that you have with dimensional lumber is to pressure treat it,” professional builder and craftsman Jordan Smith explains. “This prevents rot and fungus and bugs and other things that can destroy your material over time.”

 

Benefits of pressure treated wood

Thanks to its chemical and preservative treatment, pressure treated wood is resistant to many common problems.

  • Resistance to rot. The chemical compounds used to pressure treat wood make it resistant to fungi that cause wood to rot.
  • Protection from insects. Similarly, treatments repel common insect threats like termites and carpenter ants.
  • Cost. Pressure treated wood is more expensive than untreated wood but given that it can last for decades, it often ends up being more economical in the long run.
  • Ease of Use....
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Hardwood vs. Softwood: What’s the Difference?

There are two primary categories of wood: hardwood and softwood. Both are used in different types of construction. But the difference between the two doesn’t have to do with their actual hardness or density, it’s in how the trees reproduce.

To explain it most simply, a wood is classified as a hardwood if the seeds that the tree produces have a coating in the form of a fruit or a shell. Softwoods produce seeds that don’t have a coating, which are dropped to the ground. These biological differences do impact the characteristics of the wood, which in turn impacts their uses. Read on for a complete guide to hardwoods and softwoods.

What is hardwood?

Hardwoods are angiosperm trees, or plants that produce seeds with a covering. They usually form flowers to reproduce. They’re fertilized by birds and insects that carry the pollen to other trees, and when they’re fertilized, the trees form fruits, nuts, or seeds. These types of hardwood trees include walnut,...

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All About Wood Construction: Advantages & Disadvantages

Wood is one of the oldest building materials used by mankind.  It was used to build everything from Neolithic longhouses to the first Temple of Jerusalem, built with the cedars of Lebanon. Today, wood frame structures dominate residential construction in the United States. More than 90 percent of American homes are built with wood frames. 

However, a number of tragic urban fires—in the United States, the most significant was Chicago’s Great Fire in 1871—led builders to consider other options for taller, higher density buildings. In the late-19th and early-20th centuries, concrete and steel came to dominate the construction of taller buildings. Wood became reserved for interior details, occasionally (when treated) exterior cladding. At most, wood played a supporting role in projects where concrete and steel did the heavy lifting. 

That is changing, however, thanks to engineering advances, new protective treatments for lumber, a desire to construct...

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All About Timber Framing: History, Characteristics, Joinery

While the materials used to construct buildings are remarkably varied—bricks, thatch, stone, and more—one construction material stands out above all others in popularity: wood.  

“Early humans lived under trees. As those trees fell down, they took shelter underneath the fallen trees,” professional builder and craftsman Jordan Smith explains. “ And then it wasn't long before they figured out: You know what? We can stack these to make walls or we can lean them against each other.”

From those humble beginnings, a type of construction known as timber framing came to dominate wood construction. The Horyuji Temple in Nara, Japan, built around 600 C.E., is the world’s oldest existing wooden building, and it was constructed using the timber framing method.  

“So for everybody who has durability concerns about wood. we've got buildings that are still standing today that are 1400 years old.”—Jordan Smith 

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