The Gross Combination Weight (GCW) – also known as the Gross Combined Weight Rating or Gross Train Weight – is the weight of a trailer and towing vehicle combined as specified by the vehicle manufacturer, including the weight of the maximum loads on each. To calculate the GCW for your tiny house trailer you can simply add the maximum weight of the trailer to the Gross Vehicle Weight (GVW), as demonstrated in the equation below:
GVW + maximum trailer weight = GCW
It should be noted that – as long as the maximum GCW and the GVW of the trailer are not exceeded – any spare capacity freed up by a tow vehicle which isn’t fully laden can be used by the trailer. It's important to ensure that you don't surpass the maximum permitted GCW so that your tiny house trailer remains road legal.
