How to Measure a Layflat bag and Side Gusseted Bag Poly Bags?
Understanding how to measure the standard poly bag may be a simple task but when the bags begin to have additional dimensions such as a side gussets and/or bottom gussets measuring the bag can get a bit confusing. Below is information on how to measure 4 types of poly bags.
Layflat Poly Bags: Width x Length + Gauge
In the plastic industry the norm for measuring bags is the width always is the first number followed by the length of the bag. For layflat bags, the third number that most often follows the length will indicate the thickness of the bag. This number will often come in Mil if the bag is made from Linear Low Density Polyethylene (LDPE) or in Micron if the material is made from High Density Polyehtylene (HDPE). If there is more than 3 numbers represented than more than likely the bag will be a gusseted bag.
Layflat (No Gusset Bag) = W x L + (Mil or Micron)
3 Types of Gusseted Poly Bags:
Side Gusset:
Width x Side Gusset x Length + Gauge
Bottom Gusset:
Width x Length x Bottom Gusset + Gauge
Side Gusset with Flat Bottom:
Width x Side Gusset x Length + Bottom Gusset + Gauge
To make it easy for our customers our side gusset bags we have taken out the gusset measurement and placed it in parenthesis. However, the above formulas are the industry standards on how to measure gusseted poly bags.There are three types of gusseted bags and each one is measured differently. However, there are two commonalities when measuring any gusseted bag. First, just like measuring any bag, the width will always be represented first. Secondly, the number representing the size of the gusset is measured after the bag is fully opened. If opting not to open the bag, another way of measuring the side gusset of a bag is just measure the plastic that tucks into the bag and multiply that number by 2.
Side Gusset: If the bag only has a side gusset and no bottom gusset than the gusset will be represented by the second number. When measuring the actual gusset it is important to note that the entire width of the gusset is measured after the bag is fully expanded and this measurement represents only one side of the bag. So the example provided below the gusset will measure 3” after the bag is expanded. Another easy way to measure the side gusset is not to open the bag and just measure the tuck of the bag and multiply by two. Thus, for the example provided below, when the bag is unopened than measure the tuck (which is 1.5”) and multiply this by 2 (equaling 3”).
Example: 10” x 3” x 12” 2mil.
Width = 10”
Length = 12”
Gusset = 3”
Thickness = 2mil
Bottom Gusset: For bottom gusseted poly bags the tuck of the bag will be found at the bottom of the bag rather than the two sides. The number represented the bottom gusseted will be the 3rd number and should always indicate what the number represents. Like the side gusseted bags the gusset is measured by fully expanding the bag.
Example: 10” x 12” + 3” (Bottom Gusset) 2mil
Width = 10”
Length = 12”
Gusset = 3”
Thickness = 2”
Side Gusset w/Flat Bottom: These types of bags are considered to have both a bottom gusset and a side gusset. The side gusset will be represented by second number and is measured by expanding the bag. Whereas, the bottom gusset will be represented by the fourth number and is measured after expanding the bag. The easiest way to measure these types of bags is not to open the bag and measure the tuck of the side gusset and multiply by 2. And for the bottom gusset just measure the entire base when the bag is not opened.
Example: 10” x 3” x 12” +2 (Bottom Gusset) 4mil
Width = 10”
Length = 12”
Side Gusset = 3”
Bottom Gusset = 2”
Thickness = 4mil