Pressed Particle Board Shelving Warning

Andrew> You might want to price 3/4" marine plywood. You can cut down Andrew> one sheet and probably replace 4 to 5 of the shelves. Andrew> Home Depot's and Lowes' websites don't seem to show marine Andrew> plywood, or any plywood in 3/4" thicknesses, but you could Andrew> call around to local lumber yards. You don't have to go Andrew> specifically with marine plywood... Or furniture grade plywood. I have had a particle board bookshelf come apart. The blame was in part on incompetent design ("scandinavian design" pretty looking stuff) -- the shelf was "supported" on a groove milled in the edge. That means the load was carried on less than half the thickness of the shelf. Even so, a better material would not have failed. I think US building rules say that particle board (or its various analogs, such as OSB -- I still call that particle board) are not allowed for load bearing applications such as floors. Those must be plywood. And personally I view any house built with particle board *anywhere* (even where it's permitted) as cheap construction. So I'd say that you should never use particle board to carry loads. Solid hardwood will do, and hardwood plywood is perhaps better (doesn't warp). We now have some book shelves made of solid hardwood, some made of 1/2 inch birch plywood. For heavy loads I'd perhaps increase that thickness. Finally, keeping the spans short is a big help. paul