Understanding Paper Weights

Paper weights are one of the hardest concepts to understand in the field of office machines and paper handling. This is the one topic that stumps both rookies and professionals alike. The system used here in the US is confusing by any standards, and varies greatly from what is used in the rest of the world. In the United States, we use a system based on several factors and labeled as pound(lb.). The confusing part is that an 80 lb sheet of paper can be a completely different thickness depending on if it is considered text, cover or something else. This naming system, (i.e. text, cover etc.) is extremely important to our method of measure, but often times it goes unsaid, and this is where most confusion stems from.

In the US, and a great majority of North America, we use the imperial method of measuring paper weight. This way is highly dependent on the end use of the paper in question. What ever the most popular use for that particular weight of paper becomes it’s basis weight, which is not to be confused with its basis size. Examples of basis weight include “text”, “cover”, “bond”, etc. Each of these individual weight categories also has a basis size that is taken into consideration. The combination of the two will allow you to calculate the actual weight in pounds.

In the US, paper weight is calculated by weighing 500 sheets of each basis size. So basically the weight of the paper refers to the weight of 500 sheets of the paper stacked in a pile. This seems easy enough until you realize that the sheet sizes are different for each basis weight, along with the thicknesses.

Example:
Text paper has a basis size of 25″ x 38″ and cover paper has a basis size of 20″ x 26″. This is why it is important use the basis weight when specifying the weight of the paper you want. A good example would be to ask for 80 lb. cover paper, and not just 80 lb paper in general. An 80 lb. cover will vary greatly from an 80 lb text.

Using the US method of weighing paper, you could mistakenly, or purposely for that matter, have two sheets of the same grade of paper with two different weights. This could happen by calculating off of different basis sizes. This is why it becomes so important to always reference the basis of the paper you want. Without it at the end you will end up being confusing and quite possibly get the wrong paper. So to be completely clear when ordering paper you should say things like ” I need some 80 lb text paper” or “Please get me the 100 lb bond”. You cant just say 80 lb paper.

The other method of measuring paper weight would be the metric system, and it is widely used in most other parts of the world. It is a straight forward and comparably easy formula to understand, but is never really utilized here in the US. With the metric system, all paper weights are measured on the same scale. There are no basis weights or sizes to worry about. Each paper type is measured by how many grams per square inch are in a single sheet of paper. It is written G/M2. You will see varying weights represented in an easy to follow manner. An 80 G/M2 piece of paper would be considered text weight, where as a 300 G/M2 sheet would be considered cover weight. Notice how the larger number equals thicker paper, and there are no qualifying phrases necessary. This method of weighing paper seems easier to understand right away. Just say ” I need some 110 G/M2 paper” and everyone knows what you are talking about.

Learn More at Factory Express