I'm finally in a position to attempt to build bookcases to hold my National Geographic collection. However, I'm very concerned about the massive concentration of weight that will result. As you all know, National Geographics are very heavy!
According to my rough calculations, my collection of ~1200 issues, plus the very sturdy cases required to hold them, will result in roughly 1500-2000 pounds distributed over a tiny combined footprint of barely over 4 square feet. This would be in an L shape in a corner formed by two exterior walls of my house (not at ground level, mind you). I'm worried this will be excessive and possibly result in structural damage to my home!
Has anyone else contended with such a consideration? Am I underestimating my home's ability to support such weight? Any thoughts or advice would be appreciated. Thank you.
You can distribute the weight across the floor joists with a base board, but really don't think this is necessary.
If your collection is stored in the NG slip cases, the cases spread the weight across the shelving.
If not, then you will be concentrating more weight in a smaller footprint that would be ameliorated with the base board.
The attached photos show how I stored my collection on the first floor with with full basement, i.e. floor joist supported, for nearly twenty years before we moved:
Thank your for the response and photos. I see that you had a considerable amount of empty space between shelves and what not. Unfortunately, space is at a premium here, so my design will be much more compact and dense with very little empty space. I will be using slipcases (at least for most of the collection), so that will help somewhat.
Also, as I mentioned, this design will be in an L shape, one leg of which will be across my floor joists, while the other leg will, unfortunately, not be. I am particularly concerned with this leg and may have to buttress it from underneath even though it will be right up against the exterior wall and thus very close to the foundation? However, do you think I even need to be concerned with the leg that's running across the joints, given the amount and concentration of weight we're talking about?
Our shelving ran with, not across the floor joists. The shelving supports are 16 1/4 inch wide joined columns. The oak shelves slide inside the supports at 12 inches wide. The columns are further supported with slotted joints (much like a bed frame) between them.
That portion of your "L" that rest across the joists with not be a problem. Even though I still don't think you'll have a problem with that portion of the "L" that lies against the outer wall (supported by the foundation) you might want this side to be the shelving that rests on a wide board that spans the gap to the first joist. This will give you the "extra" support I believe you're looking for to put your mind at ease.
This means, to keep the entire project level, you'll probably want to add a base board to the first side of the "L" making it even more secure.
That's a brilliant idea! I'm thinking a solid platform in a roughly-triangular shape that the entire thing would sit on, thereby distributing the weight as much as possible. Gonna mull this over a bit. Thanks.