by James Levine, CEO, New Haven Moving Equipment

The best way to become proficient in selecting quality moving boxes is to become educated about the materials and technology employed in the process of their construction. This article will give you a quick and cursory understanding of how moving boxes are made, and the impact of this on their ability to protect what is inside.

The technical term—the term movers use for for moving boxes— is corrugated. Corrugated refers to a paper board that combines strong paper with some sort of protective fluting; and corrugated products—such as moving boxes—have been in existence for almost one hundred and fifty years. In the 1870’s, corrugated was first utilized as shipping material for containers, bottles and lamps made out of glass. In 1902, solid boxes made from fiber were developed, paving the way for the mass production of corrugated boxes. Within a year, corrugated boxes were approved for the shipping of cereal and then a growing array of other products, and by the 1950’s, corrugated gained particular popularity on farms as a means of shipping produce, given the propensity of corrugated to prevent damage to the produce. In the years since, the use and prevalence of corrugated has burgeoned, and the technology behind the design and production of corrugated has evolved to make moving boxes stronger, more durable, and even resistant to water.

What Is the Corrugated Material Made From?

Corrugated is made from a variety of sources including the following:

  1. Wood Fiber that comes directly from trees
  2. Recycled Paper
  3. Sawdust and wood chips

The various combinations of these sources, the type of wood fiber utilized, and the method by which the wood fibers are separated from each other in the paper mill will all contribute to determining the quality, strength, and durability of paper being ultimately produced. For example, to produce a particularly strong type of paper used for liner board (see below), the mill or corrugator will utilize the sulfate or “kraft” process to separate the wood fibers. The kraft process is a chemical method for fiber separation that is the most protective of the integrity of the fibers. (There are several other mechanical and chemical processes available for fiber separation). In producing liner-board, the mill will also select softwoods as its source of wood fiber. Softwoods are known for the elongated length—and hence resiliance— of their fibers.

The Composition of a Moving Box

Essentially, the finished Corrugated Moving Box is made from Containerboard (a term for heavy paper) and is composed of two types of material which have been glued together:

  1. Linerboard—which serves as the flat surfaces on the outside and on the inside of the moving box. This thick cardboard type material is generally over .01 inches thick. During the process of manufacturing the corrugated, the liner board is attached to the Medium, often with an adhesive.
  2. The Medium, also known as the fluting—which serves as the wavy and cushioning layers inside of the box. As a result of their arched shape, the flutes actually gain the capacity, despite their being made from paper, to hold a substantial amount of weight and provide cushioning and protection to the box’s contents. Hence, the more layers of fluting within a box, the stronger, more protective, and more insulating the box can be.

CATEGORIZING FLUTING. The fluting within a moving box (made from a combination of special fluting paper and recycled fluting paper) is rated as A, B, C, E, F. The sequence of these letters reflects the order in which the fluting was first invented, and each letter corresponds to a specific number of flutes per linear foot. Generally, a larger size flute will produce enhanced cushioning, insulation, puncture resistance, and vertical compression strength. However, there are times when smaller flute sizes will provide structural advantages in certain types of boxes. It has become progressively more standard over the years for corrugators to manufacture moving and storage boxes that strategically juxtapose several types of fluting (each with specific advantages and possibly disadvantages) in order to produce a specific, desired outcome.

Given the large role that fluting plays in determining the quality and strength of a box, moving boxes are often categorized as either single wall (which means there is one medium or set of fluting in-between two linerboards), double wall (which means there are two mediums or two sets of fluting encased within three linerboards) or triple wall (which means that there are three sets of medium or fluting encased within four linerboards). A moving box can also be called a single face, which means that there is only one medium or set of fluting glued to only one liner board rather than the medium being incased within two liner board (as you would see with a single wall).


Corrugated material is produced in machines called corrugators, or sometimes flute lamination machines. Corrugator machines are extremely large—often 300 feet long and 20 ft. high. These machines adhere the flutes to the medium and the medium to the linerboard. During this process, technological processes or modifications can be made in order to eventually make the corrugated box more resistant to tearing or to water damage. It is important during the production process to avoid warping and washboarding. All that transpires during this process contributes to the ultimate qualities of the box.

The quantity of recycled corrugated used in a box (that is. the percentage of recycled corrugated vs. non-recycled, virgin corrugated) as well as the process by which used corrugated material is recycled, can also play a crucial role in the qualities of a box. The process for recycling corrugated material involves many technological and mechanical steps, including being compressed, baled, and submerged in a hydropulper.

Boxes are currently evaluated using something called the Edge Crush Test (ECT), which is an objective measure of how well a corrugated box can withstand being crushed, The ECT is the industry’s most modern, laboratory based exam capable of determining the durability and strength of a moving box. It is commonly believed that a moving box should have an ECT score of at least 32.

PUTTING IT ALL TOGETHER — What to look for

As you can see, there are several factors that work together to produce the specific qualities, advantages and vulnerabilities of any given corrugated moving box. These include such obvious factors as the strength of the linerboard, the number of flutes used per linear foot, the flute thickness, and the number of walls—along with such non-obvious factors as the type of wood fiber utilized, the process utilized to separate the fibers, the methodologies employed during the recycling process, and the percentage of recycled paper utilized in the production of the container board and fluting paper.

When purchasing a corrugated moving box, there are specific expectations you will have in order that you can pack and move with confidence. You need to know all of the following:
  1. that your box will have great “stackability” and not sag when stacked in the moving truck
  2. that your box will not give way to internal or external pressure and can resist crushing, tearing and damage
  3. that your box can provide you with full and safe protection for your valuables.
However, with many of the boxes on the market today, you may not necessarily be assured of these qualities. Moving boxes may appear average to the naked eye, but may in fact sag, rip and be easily crushed during the packing, stacking, moving and transportation process, thereby risking the safety of your possessions. Therefore, it’s important to trust the source of your boxes.

New Haven Moving Equipment has been a leader in the industry for over one hundred and five years, and is known for the quality of their products, innovative engineering, and outstanding customer service. Because of New Haven’s expertise and years of experience, they are able to provide very economical pricing on their corrugated moving boxes while still maintaining high standards of quality control.

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