Dimensional weight is also known as volumetric weight. It is used by shipping providers to compensate for larger items, which physically weigh less and take up a larger volume of space. When shipping products, you as an online merchant, must use either the physical weight or the "DIM weight" in your shipping weight calculations - whichever is greater. DIM weight is a tactic used by freight carriers to ensure they don’t lose money on large items which may be lightweight but take up a larger volume of space on their transport vehicle(s).
To calculate dimensional weight you must use the package’s Length X Width X Height and divide by a "common factor". You have to be careful though, as most carriers may use a different "common factor" depending on whether you are shipping domestically, or internationally. The common factor can also be different when shipping by land, sea, or air and the actual mode of transportation.
You have to check with your specific carrier to find out the “common factor” for different modes of transportation services.
For example, if you have a product that physically weighs 4.5 Kg (=10 lbs.), but is “oversized” and measures 129 cm (L) x 45 cm (W) x 38 cm (H) - the dimensional weight is actually 36.8 Kg.This example was calculated using UPS standards for “Domestic and Export Shipments”. In comparison on this example, the DIM weight for “Import Shipments” with UPS works out to 44 Kg based their import standards into North America.
In ShopFactory, using the final weight whether physical or dimensional (whichever is greater) is quite easy to implement. The weight entered is then used to calculate the final shipping cost with your carrier’s automated shipping calculator in your shop.
When setting up a product, you simply enter in the greater value of the physical or DIM weight calculated in the product set-up window:
Also when setting up your shipping carrier’s rate calculation service in ShopFactory, you should use the “Surcharge” feature in the set-up window to increase your margin on shipping slightly.
You can use this feature to compensate for small variances and hidden carrier costs that sometimes show up on your bill from time to time. Some of these unforeseen charges may include: Incorrectly entered physical or DIM weights, Address correction & redirect charges, fuel surcharges, daily pick-up charges. Or, you can simply increase your actual profit margin on shipping to ensure you cover all your shipping and handling expenses - which can make a big difference in your bottom line at the end of the year as it all adds up over time.