Clear the area where you intend to put the bookshelf, including enough space in front of the bookshelf to work. Measure the bookshelf area from side to side. Determine if there's at least 16 inches of space from front to back in which to fit the cinder blocks. You will need one cinder block for every 3 feet plus an additional cinder block at the far end.
Place two cinder blocks, perpendicular to the wall, at each end of your bookshelf. Distribute the intermediate cinder blocks evenly. For a 6-foot bookshelf, you would use three cinder blocks. For an 8-foot bookshelf, you would use four cinder blocks.
Cut three boards for each shelf to the length of your cinder block layout plus 4 inches.
Lay three boards side-by-side on top of the first set of cinder blocks. Align the ends of the boards and make sure they extend equally on either side of the cinder blocks. The front board will extend about 1/2-inch beyond the front of the cinder blocks.
Check that the boards are level both front to back and side to side. If not, use shims under the cinder blocks to even them.
Place one cinder block directly over a cinder block on the lower level to create a second shelf. Lay the planks across cinder blocks as before and check that it is level again.
Things You Will Need
- Measuring tape
- 3 boards, 1-by-6-inch, per shelf
- 2 to 4 cinder blocks per shelf
- If you are laying your bookshelf on carpeting, check for level after several days.
- As long as the cinder blocks and planks are level, you can continue adding shelves.
- Several improvements can be made to the basic design. Sand the edges of your sawn wooden planks before assembling the bookshelves. Stain or paint the wood planks before assembling the bookshelves. Spray paint the cinder blocks and allow them to dry before assembling the bookshelves. Spray painting the cinder blocks not only adds color, but it will reduce the dust from the cinder blocks.