Expert: Dan Griffin - 12/31/2009

Question
My wife wants to purchase a safe for our second floor.  It's dimensions are 20" x 22.75" and weighs 400 pounds.  Is it safe to put it on the second floor?  House was built in 1997 and Im going to guess that the joists are 16" on center (at least they are in the basement.

Answer
Ryan, this boils down to about 131 lb/SF.  This is a substantial load and needs to be considered when locating the safe.  Most bedroom floors are designed for 30#/SF.  It becomes important to locate this concentrated load at either the end of the joists or over a bearing wall below, not out midspan in the center of the room.  This will require knowing which way the joists run - typically they run across the shortest dimension of the house.  I assume you are planning on placing this in a closet or similar.  If you could add framing or at least an additional sheet of 3/4 ply to help spread this load to as many joists as possible will help.  I do NOT fear that you are headed for any type of instant collapse, think about this load as one very fat man or two good sized fellas standing mighty close together.  The load is substantial, but not devastating.

The biggest problem I see is toting that 400# safe up the stairs.