The Decision Depends on the Job
Knowing when to choose a different paper from the standard can be overwhelming. The answer depends on the type of job you are printing and what is your intent for the final product.
Here are some things to think about when you are deciding on paper choice.
Type of Ink?
If you are printing in black and white, most likely you will be using regular 20lb paper. This is the cheapest choice, and is more than adequate for most simple jobs.
If you are printing in color, then you will need to consider the final need for the printing job. Ask yourself these questions.
What is the Intended Look?
The more professional you want your print to look, the more you should consider using higher quality paper. This paper will be slightly heavier, and will include a coating of either gloss or silk. If you are working within a budget, regular laser text is an adequate substitute, but will not give it that pop that you may be desiring.
How much Durability do I need?
What is the intended purpose? If you need strength, or for something to last longer, choose a heavier weight text or even a cover stock which is typically called index or cardstock. If it will be heavily manhandled, for example by the post office, or used heavily like bookmarks, then definitely choose the heavier index weight paper. An informational flyer that you know could quickly be discarded, could be printed on the lightest text weight paper.
What is the Purpose of this file?
For informational flyers, a light text weight is sufficient. By spending more for the glossy or silk finish, you will upgrade the look of your flyer. The 24lb laser or the 80lb glossy or silk text is a wise decision. For larger size flyers like 11 x 17 or 12 x 18, a slightly heavier text weight of the 100lb text can be considered for strength while tacked to a board for some time.
For Brochures or folded pamphlets, a heavier text weight is ideal. It has the durability of the heavier weight stock, and the lightness of regular text weight. The best choice for this is 100lb glossy or silk text.
Booklets can be confusing. Do you go with all the same weight, even for the cover? Or do you choose a heavier text weight for the cover and lighter text weight for the inside? This second option will give you a sturdier booklet allowing the cover to take the brunt of the manhandling force, while the lighter text weight will keep the booklet from becoming too heavy or cumbersome. This works for either left corner, 2-side stapled or saddle-stitch booklets. If you are planning on using a clear front and a black back for your booklet, then keeping the entire booklet the same weight makes sense.
For Business Cards, you will want the heaviest weight index. Choose the 120lbs glossy or silk index.