What Is 2×6 Actual Size? Nominal Size And Actual Size
For almost all DIY projects that involve lumber, the 2×6 size is commonly used in the frame construction for walls.
This is the best choice because it provides more space between exterior and interior walls. This helps to retain more insulation, and reduces outside noise.
Thick walls can be used to separate a living area from a garage. They will effectively screen out the noise and chaos of the garage. If you want to soundproof your home more effectively, then 2×6 is the best choice.
The 2×6 will also make a great choice for an outhouse. You can build an outhouse with a single story using these sturdy, soundproof materials.
With a 2×6, there’s no need to worry about walls vibrating if you close the door too hard. When you properly insulate your home and seal the air leaks, you can expect to pay less for energy.
If you are new to home improvement projects, you may be surprised to find out that a two-by-six isn’t really a two by six. Let’s look at what the size of a standard 2×6 is and why.
Lumber Dimensions and Size
Dimensional lumber is lumber that has been cut to standard sizes. The dimensions of the lumber are measured by its depth and width.
Softwood is commonly referred to as dimensional lumber, and it forms the main structural element of residential construction. These lumbers are commonly used for framing and construction. They are an essential part of many construction projects.
They are the same size throughout the country, and so can be used in the entire house or between homes.
The product you receive from the store, whether you buy softwood or hardwood lumber is dimensional wood with nominal and actual dimensions that vary.
The nominal or marketed size is 2×6. However, after the lumber is processed, it is reduced to 1 1/2 inch x 5 1/2 inch, which is its actual size.
A 2×4 is 1 1/2 inch by 3 1/2 inch, a 2-by-8 is 1 1/2 by 7-14 inches and so on.
Read: How Long Does Wood Glue Take To Dry
Basic Dimensions of Lumber
The basic dimensions are the width and depth of the lumber. A 2×6 means that the lumber measures 2 inches deep by 6 inches wide.
It is important to note that a piece of lumber has the dimensions depth x width + length. However, it is only ever referred to as lumber by its width and depth.
The nominal and actual lengths will be almost identical because the length of the lumber remains the same after processing. A 8ft lumber will come very close to being 8 ft.
What is a 2×6 actual size?
A 2×6 measures 1 1/2 inches by 5 1/2 inches.
You will find that when you use a measuring tape, the measurements do not match those of the 2×6 piece purchased from the lumber yard or the hardware store.
Lumber is sold by its nominal dimensions. The nominal size is the dimension according to which lumber was originally cut. The nominal size is the same dimension that is used to advertise and sell the lumber.
The wood is processed before being sold after it has been cut to the nominal size. The wood is then milled, sawed, and polished, resulting in a smaller size of lumber.
The resulting dimensions will be slightly smaller than nominal size, and they will indicate the true size of the lumber.
The nominal size of 2×6 is actually 1 1/2 inches by 5 1/2 inches. Dimensional lumber is what a 2×6 is.
Lumber Dimensions: Nominal and Actual Size
Dimensional lumber is available in nominal and actual sizes. After the wood is cut to its nominal dimensions, it undergoes a variety of processing, including milling, smoothing and polishing. All of these reduce its size.
In reality, lumber cut to nominal dimensions of 2×6 is not 2×6 but instead 1 1/2 inches by 5 1/2 inches.
This size reduction does not happen at random, but rather follows a set of rules. Here are some rules to help you determine the size of lumber when you know its nominal dimensions:
- The nominal size of sizes smaller than 1 inch is reduced by 1/4″ to obtain the actual size.
- Actual size for nominal sizes 2 to 8 is 1/2 inch smaller.
- The actual size of a nominal size larger than 8 inches is 3/4 inch smaller.
Read: 2×8 Actual Size
Nominal Lumber Dimensions
The nominal lumber sizes are sold and therefore need to be whole number that is easy to remember. Although they do not represent the actual product size, they are the most common size.
Although it may not be the exact size, a 2×6 is still called 2×6 because that is its nickname or marketed size.
Actual Lumber Sizes
When you use a measuring tape, the actual lumber size is what you see. The actual size of a 2×6 is 1 1/2 inch x 5 1/2 inch.
Read about: The Woodworking Symbol of Feet and Inches explained
The Dimensions of the Actual and Nominal Sizes Must Match
The current lumber dimensions have been used by lumber yards since the 1870s, even though the term “dimensional lumber” was not coined till 1920.
You will never find nominal and actual dimensions of lumber that are the exact same.
If you are tearing down an old house, one built before 1870, you may notice that the wood is larger than you would normally receive at a hardwood shop. If you measure the lumber, you’ll find that it was really 2×6.
The lumber that is used today has a different standard, so if you reuse it, it will stick out the wall. You can cut it to the current standard size of 1 1/2 by 5 1/2 and reuse it.
Based on Material
The nominal and actual sizes of wood are different. When you visit a local lumber store, however, you’ll notice that the sizes are not only different, but they also differ inconsistently.
Hardwood lumber is polished more and does not follow this rule.
Plywood and Sheet Goods
Plywood consists of several thin layers that are sandwiched to create a stable and strong lumber piece. Plywood is available in a variety of sizes, both nominal and actual.
The nominal sizes are 1/2 inch or 3/4 inch for cabinets. The standard nominal sizes are 1/2 or 3/4 inch for cabinets (actual size is 23/32).
The plywood is graded either on the face or both sides. The plywood is graded as A (best, with the smoothest, sanded-finish), B, C or D.
The plywood graded AA will have an A grade finish both sides. The plywood graded DD will have a finish grade of D on both surfaces.
Hardwood Lumber Lengths
The nominal length of hardwood lumber is usually very close to its actual length. Standard sizes are 8 ft and 10 ft up to 24 feet.
A 8-ft piece of lumber can have a maximum reduction in length of 1/4 inch. This is not significant.
Hardwood Lumber Dimensions
Standardizing hardwood lumber dimensions is confusing because it depends on two factors.
- The number of surfaces polished (one side S1S, or two sides S2S).
- The standard measuring system is used to measure hardwood.
To remove saw marks and smooth the surface of hardwood used in cabinetry and furniture it is necessary to polish its surface.
The sizes of some of the sizes, before and after polishing
Nominal Thickness (in Inches) | S1S (in inches) | S2S (in inches) |
1/2 | 3/8 or 9mm | 5/16 or 7.9mm |
1 | 7/8 or 22mm | 13/16 or 21mm |
3/2 | 11/8 or 35mm | 15/16 or 33mm |
2 | 29/16 or 46mm | 13/4 or 44mm |
3 | 45/16 or 71mm | 11/4 or 70mm |
4 | 61/16 or 96.5mm | 15/4 or 95mm |
Quarter system
The thickness of a board is measured using the quarter system. This means that it is measured as quarters, or 1/4 inch. A 4/4 board measures 1 inch. A 5/4 measures 1 1/4 inches, a 6-4″ is 1 2/4 inches, etc.
Normally, 1/4 inch of the thickness is removed during processing. If you need a board that is 1 inch thick, you’ll have to purchase a board that is 5/4 or a 1/4-inch thickness. This will be milled down to 4/4 or 1 inch thick.
Board Foot
The volume of lumber is measured in cubic inches, so 1 board foot equals 144. For a board that is 1 inch thick, both the length and width will be 12 inches.
Hardwood also does not come in standard widths. You will have to cut it to the size you need for your project.
Dimensions of Glue-Laminated Timber
Glue-laminated wood is made up of layers of dimensional timber that are glued together with adhesives to form structurally engineered lumber. Not only are glue-laminated woods available in standard sizes but they can also be customized.
The depth ranges from 6 to 72 inches and the width from 2.5 to 10.75. Each piece can be customized to a length of up to 100 feet.
Both nominal and actual dimensions of glue-laminated wood are almost identical. The nominal and actual width sizes differ.
Below are some width differences:
Nominal width in inches | Actual width in inches |
3 | Two-quarters or five-two |
6 | 5 1/8 or 112 |
10 | 8 3/4 or 35/4 |
12 | 10 3/4 or 43/4 |
16 | 14 1/4 or 57/4 |
Softwood Lumber Lengths
The lengths of softwood lumber are nearly the same, both before and after processing. The milling, the sawing and other methods of processing have a minimal impact on its length. Standard sizes start at 6ft, and go up to 24ft in 2ft increments.
Softwood Lumber Dimensions
The width and thickness of softwood lumber are different from their nominal sizes. Softwood lumber is treated the same way.
The FAQ
Why is dimensional lumber smaller than nominal dimensions?
The lumber is first cut to the nominal size, and then it undergoes a processing process that reduces its actual size. The actual size of dimensional lumber will be smaller than its nominal size.
How far can a 2×6 span?
A 2×6 spans 12 feet 6 inches as a floor beam, 18 feet as a rafter and 20 feet 8 inches for ceiling joists. It can span 9 feet 11 inches to be a deck joist and 24 feet for a board.
How wide is a 2×6 board in reality?
A 2×6 piece of wood is actually 5 1/2 inches long by 1 1/2 inches wide.
The conclusion of the article is:
The nominal size of dimension lumber does not correspond to the actual dimensions. The nominal size is the dimension of an unfinished, raw product.
The actual size of the product is smaller than its nominal size. The actual dimensions of a 2×6 are 1 1/2 inches by 5 1/2 inches.