Now of course a roof rack is going to have curvature so it isn’t going to look the same, but the volume will be the same.
1 cubic foot = 7.48052 US Liquid Gallon. Pretty much any cargo box over 10 cubic feet will be able to fit 3 snowboards or more if you’re looking for a comparison.
I'm the owner of Beast Auto. I live in Phoenix, Arizona. I love anything automotive related, and taking road trips all across my beautiful state.