One of the most common beginner woodworking mistakes is making inaccurate measurements. This could lead to wrongly estimating the quantity of finish you need for a project, cutting pieces of wood that don’t add up or buying more or less lumber than you need.
Often, these mistakes are due to not knowing the feet and inches symbol for woodworking. So, in this comprehensive guide, we’ll provide all the information you need with detailed examples to know the feet and inches symbol for woodworking.
Sounds good? Keep reading!
Feet and Inches Symbol?
Feet and inches are usually represented as either an abbreviation or symbol. The IEEE standard symbol for foot is “ft.” or is symbolized as a prime, which is an apostrophe (‘). So 8’ means eight feet. Inches are abbreviated to “in.”, or less often as “ins.” for inches, and are symbolized as a double prime or double apostrophe (“). So 5” means five inches tall.
Why do we Use Feet and Inches for Measurement?
Feet and inches are the standard modes of measurement in the imperial system, which is used in the United States and a few other regions. This is vastly different from the metric system that used meters and centimeters.
When breaking it down, one foot is equal to 12 inches. This is because inches are the smallest unit of length in the imperial system. However, in the metric system, one inch equals 2.54 centimeters. This will come in handy when converting from meters to feet or centimeters to inches).
Feet and inches can also be represented by their symbols, which makes them quicker to use. For example, writing 5′ is considerably faster than writing five feet or 5 feet, just as writing the inch symbol – 2″ is more efficient than writing 2 inches tall.
Combining both is seamless – 5′ 5″ beats writing five feet and five inches. Of course, these can also be abbreviated to 5 ft 2 in, although it doesn’t quite have the same ring.
Meters can also be abbreviated to “m,” but this can be confusing as it could represent different things like a mile, minute, or mass. So, once you get used to the symbols for feet and inches, you’ll be able to get work done faster without confusion.
Why do You Need to Understand the Symbols for Feet and Inches?
Most places will only list dimensions according to symbols when buying lumber from a lumberyard or online. That is because most buyers are industry professionals and builders that are used to the symbols, so the sellers don’t find the need to spell them out.
For example, you will see specifications like 2 x 4 x 4′, which means the piece is two inches thick, four inches wide, and four feet long. You will get confused if you don’t understand the symbols for feet and inches!
What is the Symbol of Feet?
Lumber, boards, sidings, pipes, and shingles tend to be measured in feet. Anything longer than the length of your arm will be measured in feet.
One foot or feet are abbreviated as ft, which is easier for beginner DIYers to understand. However, most hardware stores and even virtual stores prefer to write the symbol for feet, which is an apostrophe (’). This differs slightly from inches, which uses a double prime or double apostrophe (”).
Let’s take a real-life example.
Nobody has time to write inches and feet when you go to a lumber yard. So instead, you might see a measurement like:
2x4x8’. This means the board is two inches thick, four inches wide, and eight feet long. This can also be shown as 2in. x 4in. x 8ft.
You can also see products listed as:
2×4 in lengths 8-16’. This means they have two inches thick lumber and four inches wide lengths between eight and sixteen feet. However, a 2×4 size isn’t two inches thick but one and a half inches thick, but we’ll discuss this later in the article.
What is the Inch Symbol?
For inches, we use the double prime marks or double quotation marks (”). You can also find it abbreviated as in. for inch and ins. for inches. However, many people use in. for both the singular and plural.
For example, when buying a small piece of basswood for your woodcarving, you may see it listed as:
1.5 x 1.5 x6″ This means the block is 1.5 inches thick, 1.5 inches wide, and 6 inches long. It can also be represented as 1.5 x 1.5x 6 in.
It is important to note that when buying lumber, you might not always see a symbol for inches, such as:
2 x 4 x 8′. This means the piece of lumber is two inches thick, four inches wide, and eight feet long. Every time you hear someone say a 2 by 4 or 2 x 4, they refer to inches.
Why Use Symbols Instead of Abbreviations?
You might be wondering why symbols are more popular than abbreviations. After all, it is impossible to misunderstand an abbreviation, while the symbols for feet and inches can be confusing because they are nearly identical.
Well, there are three very good reasons for that.
Speed, for faster denotations
Woodworking is a time-consuming industry. So, wherever or however you can save time makes a huge difference. For example, when you work in a company that sells many woodworking tools, using symbols will save you a lot of time. The same applies to tradespeople who are constantly taking measurements, like builders and carpenters.
Having to write feet and inches after every number can get repetitive and longwinded. Symbols are a fast and effective way to get measurements so you can quickly get back to work. Also, it is quicker to write ” than to write inches, as it’s quicker to write than to write feet.
It saves space, allowing for more measurements to fit on one page
From a practical standpoint, the brevity of symbols means you can convey a lot of information in a very small area. Imagine looking at a blueprint where all the numbers have inches and feet written in full – every door, walkway, slab, wall, step, shingle, etc. That would be way too much information, plus that would be a really large blueprint.
The same applies if you are preparing pieces of wood for a project and have to write measurements on the different parts. Again, writing symbols will save space, making it easier to clean and keep the wood neat.
Comprehension – it can be universally understood
Finally, woodworking is not limited to one country or one language. Having a common means of communication makes work easier. For example, while abbreviations must be interpreted in different languages, the symbols don’t.
So, if you want to import products like a special hardwood floor, you can easily understand the dimensions. Plus, you wouldn’t need an interpreter if you visit another country and see distances in symbols.
Conversions Between Feet and Inches
Now, we get to the easy part. Converting feet to inches, or vice versa, is easy because one foot is equal to twelve inches. So, if the measurement is longer than 12 inches, you can convert it to feet by dividing it by 12. Then, to convert feet to inches, you multiply by twelve.
For example, to convert 24 inches to feet, you divide by 12 and get 2 feet. You will have a remainder if you convert a figure that isn’t a multiple of 12.
Converting 34 inches to feet will yield two and ten inches, which can be written as 2’ 10”. Converting feet to inches is a lot easier – multiply by 12. So 3’ to inches would be three multiplied by 12, which gives thirty-six inches.
What happens when you have to convert inches in decimal places to feet? For example, when you are buying lumber, measurements are often in decimal, such as 1.5 x 3.5. However, if you have bought eleven pieces of these and want to know the total width in feet, the math is still the same – divide by 12.
In this case, we are converting 38.5 inches to feet, so that would be 3 feet and 2.5 inches, or 3’2.5”.
How are the Dimensions of the Lumber Board Measured?
As we began this article talking about lumber, it’s only right we expand on it a little bit. The measurements for lumber are some of the simplest and most misleading in the industry. To understand this better, we need to break it down into the different ways lumber is measured.
Dimensional sizing
This is the most common method of measurement used for DIY lumber and construction. Lumberyards typically list the dimensions in terms of inches only, as they are sold in varying lengths.
For example, lumber is listed as 2×6 – two inches thick and six inches wide.
However, those are not the actual dimensions. Lumber is sold shorter than the listed dimensions because what you buy was planned from the actual dimensions’ rough logs. So, a 2×6 actual size is 1.5 inches thick and 5.5 inches wide.
Quarters sizing
If you want to buy rough-sawn lumber, you must get it in quarters. Quarters sizing refers to how thick the lumber is, measured in quarter increments. For example, you may see a piece that ,is “4/4” which means the board is 4 quarters or 1-inch thick.
The width is not measured because they assume you’ll first plane the lumber and then join them to the desired thickness.
Board foot sizing
Finally, we probably have the most confusing one, but you have to know if you’ll buy a lot of rough-sawn lumber. This is much cheaper than planned lumber and is sold in measurements called a board foot (bd. ft.), which is 144 cubic feet.
This is derived by multiplying 12 inches long by 12 inches wide and 1-inch thick. To buy lumber for a project, you must first calculate the bd. Ft. by multiplying each side together and then dividing by 144.
This might be a bit more complicated than buying planned lumber, but at least you’ll always get the right dimensions and not approximations.
FAQs
What is the symbol for feet and inches?
The first symbol for feet is the abbreviation (ft.), so not technically a symbol. The actual symbol is an apostrophe (’). So, 6 feet becomes 6 ft. or 6’. The abbreviation for inches is (in.) or (ins.), while the symbol for inches is a double prime (”). So, 4 inches becomes 4 in. or 4”
How do you write height in feet and inches?
The two most common ways of writing height in feet are with an abbreviation (ft.) or the prime symbol (‘). For example, five feet will be written as 5 ft. or 5’. Inches are also written as either an abbreviation (in.) or double prime (“). To write five feet and five inches tallbe would 5’5” or 5 ft. 5 in.
How do you convert inches to centimeters?
Converting inches to centimeters is rarely done, but it is possible. One inch is equivalent to 2.54 centimeters, so you can easily convert inches to centimeters by multiplying by 2.54. However, to convert from centimeters to inches, you divide by 2.54, which can yield remainders, hence why this conversion is rarely done.
How many inches tall is one foot?
One foot is the equivalent of twelve inches. This is slightly longer than the Roman Foot, which is an outdated unit of measurement that was equal to 11.64 inches. Foot, as used in the imperial system, is the same as the international system, also called the metric system.
Are lumber measurements the exact size?
No, the measurements stated on lumber are not the exact size. For example, a 2×4 is meant to mean 2 inches thick and 4 inches wide. However, it is 1.5 inches thick and 3.5 inches wide.
What is the difference between the metric system and the imperial system?
When it comes to measurement, the metric system uses easily divisible figures and follows a natural progression from millimeters to centimeters to meters. However, the imperial system does not follow a strict pattern, as you move from one inch to one foot to one yard, where a foot is twelve inches, and a yard is three feet.
Final Thoughts
Mistakes are a part of woodworking, but some errors are more costly than others. Getting a handle on the feet symbol and inch symbol will prevent you from making costly purchasing, measurement, or construction errors.
While the abbreviations are pretty easy to understand, the symbols might take a bit of getting used to. That is why we made an effort to repeat the symbols quite often in this guide so that they will be in your subconscious.
Before you jump on the next project, we’ve written another article to help you better understand the actual dimensions of a 2×8.