Dana, The architect or building engineer should know (or be able to find out) the floor load capacity which is usually part of the "as built specifications". But you can determine what the actual anticipated load is for the file room. You need to know the weight of the shelving, plus the weight of the items to be stored at full capacity. Add all the weight of shelving, boxes, desks etc and divide by the total square footage. Older buildings were built with higher floor load capacities, but newer buildings often reinforce the floors only where they know there will be heavy weight loads. A typical full 12x15x10" box will weigh approximately 25-30 lbs. but you can verify this by weighing a few samples that are typical of your storage boxes. Next you need to determine the weight of the shelving. You mentioned shelving sections of 15 x 42" and 7 shelves - what is the actual height, 84 or 96"? A shelving vendor can give you the weight of one section (or you can find a catalog of shelving and find the weight yourself). You need to know the actual dimensions including height. There may be some differences between four-post and cantilever shelving. Then you can multiply by the number of sections you have. Be sure you are counting each section - a two sided section counts as two sections. This is very basic for your calculation. If you need to be more precise, you will need to know the weight difference between the initial section and then the weight of each add-on for a row of shelving. Hopefully a ballpark figure will meet your needs. Are you designing the shelving layout? Be sure to include good aisle space. The tighter your configuration, the higher the floor load per square foot. If you need some help, give me a call. Mary Mary W. Haider,CRM Records Manager W.W. Grainger, Inc. Mailstop B4.T46 847-535-1560 List archives at http://lists.ufl.edu/archives/recmgmt-l.html Contact [log in to unmask] for assistance