Hi, interesting question, maybe you can distinguish building the warehouse (per m³ e.g.), which is then used per item of stored good to a very small extent in a "warehousing" process (say, the warehouse "lives" 40 years, in this time, for one m³, how many products do you store - so that you e.g. need 1/(40*365*20) m³ for each stored good if you store 20 goods/day per m³) and operating the warehouse (needing electricity etc.). But in principle on the right track I would say.