Heimsath Architects The bottom is a 2x member that is secured through the drywall to the studs. The top is 1x material that is screwed into the 2x from the top. There is also a 1x2 under the shelf for added support (and to match some of the crown details in the rest of the house). We designed the 'crap rail' (as compared to a chair rail or picture rail) to hold stuffed animals, trophies etc. so not a huge loads. if you are thinking books, the design would need to be beefed up.