Expert: Dan Griffin - 5/15/2011

Question
Dear Dan,
        Sorry to trouble you.  I have an open, or double-sided, bookcase, 6'x 6'x 15",dividing a large room upstairs.  On the ground floor below, there is a slightly larger room, 14' x 10', and the bookcase bisects it, that is to say, the bookcase above is furthest from the walls of the room below.  I weigh about 10st.  I suppose one must think of the bookcase as one big book and think whether that and my weight is such as to be dangerously heavy.  The house is a 1930's semi-detached.

 Yours,
         Stead.

Answer
Stead, floor loading is very subject to the weights involved.  I assume that you are telling me that the bookcase and all the materials that are on it weigh about 140 lbs.  The base of the unit is 15" x 6' which is about 7.5 SF.  YOu are applying about 19 pounds per square foot.  Typical house loading and current code requirements for residential space would accommodate 40#/SF so you should be well within safe limits.  If you load the unit solid with books I suspect you will be closer to 100#/SF which would be overloading the floor.

Hope this makes you feel better.