I am building a large bookcase, 12 feet wide by 5 feet high. Not a problem if it sits on the floor but the twist is that I must raise it up 18" due to a wall to wall hot water baseboard heater and electrical outlets along that wall.
I plan to use use 9 heavy-duty angle supports (rated 125 lb load) every 16 inches on the wall and wood support legs (1 inch decorative spindles every 3 feet on the front edge of the 12" depth unit. I estimate the load to be close to 800 lbs of books and items plus the lumber.
I have a few questions:
I believe I have sufficient load support. The brackets alone support 1,125 (9*125) lbs. With the additional front leg support, does this provide ample support?
What kind of screws should I use to hold the brackets? The sheetrock is 5/8 thick and the support bracket is 1/8". I don't want the screws supporting the brackets to snap under the load. Would 3" steel nails be better?
The leg supports are 1" spindles. Would it be advisable to use a 4X4 baluster - the kind used at the end of a staircase. Obviously a 4*4 would provide a ton more support - but its bulkier and less attractive -- but is it overkill? I guess I can space them every 4 feet?
Thanks for any assistance!
PS - The unit would be secured at the top. It will reside in a space that has a soffit for ductwork and will be secured to the crossbeam for stability, so no danger in tipping forward.