Building Supplies

What is Freight Class?

When you ship your products as LTL (less-than-truckload), you will need to assign your shipment a freight class number. The freight class number is a standard code published by the National Motor Freight and Traffic Association which allows carriers to quickly identify qualities of the shipment and assist with transportation logistics.

Building supplies come in a variety of shapes, sizes and weights. Because of this, the freight class for building supplies can range from 55-125. We list some common supplies and their associated freight class codes here. Generally, the lower the freight class code, the cheaper the shipment will be.

How to determine Freight Class

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Density is identified by the dimension and weight of your shipment. Items like fiberboard and ceiling tiles can have varying freight class codes based on the density of individual pieces.

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Does your shipment require any special handling? Supplies like cement must be shipped in drums or bags, which can affect the freight class code.

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Liability is defined by the value of your shipment and its likeliness to be stolen or damaged. Fragile building supplies like ceramic or clay tiles can increase your shipment’s freight class number.

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Are your supplies difficult to stow or transport? Heavier or unconventionally-sized items such as cabinets and garage doors can increase your shipment’s freight class, increasing your cost to ship.

Freight Class Commodities


Building Bricks

Fiberboard, Hardboard, Pulp Boards, Ceiling Tiles

Wood Brackets



Rolling Doors, Garage Doors

Ceramic or Clay Tiles

Flooring, Wood Flooring


55, 75

55, 70








Density less than 30 will result in class 70, everything less will be class 55.

Density less than 35 will result in class 70, everything less will be class 55.

Must be shipped in drums or bags.

Common Commodity Items



For many NMFC® codes there isn’t just one single class that is applied. Often, NMFC® numbers have multiple "sub-classes", which are almost always based on the density of the shipment. In the instance where your NMFC® number has multiple sub classes, it's best to contact an expert, like Koho, to help identify which subclass to use.


What if my building supplies don’t match any of the items above?

Building materials can be wide ranging in size, material and use. It’s important to consult with a Koho expert if you’re unsure which class you should be using.

‍What class should I anticipate for building materials?

‍Building materials tend to be denser in size, so generally speaking you should be shipping with a lower freight class unless the item contains special features or is particularly less dense.