You might think of a rolling library ladder as the kind of luxury only seen in high-end book stores, but it's really a space saving device. Having a secure ladder lets you use more of your vertical wall space for book storage, leaving more space near the floor for furniture and pictures. Library ladders and rails are normally sold as kits. The rollers for the ladder are usually sized to fit specific rail dimensions, so it's always best to get all the parts from the same supplier.
Determine the proper height for the ladder rail. This is based on the length of the ladder in the kit. Generally an 8-foot ladder will need a rail 91.5 inches from the floor; the rail height for a 9-foot ladder should be 103.5 inches, and the height for a 10-foot ladder should be 115.5 inches. Verify these measurements with manufacturer's suggestions.
Climb the step ladder and use the stud finder to locate the wall studs along the area where you want the rail, and at the proper height for the rail. Mark the stud centres with a pencil.
Install the rail brackets by driving screws through the holes in the brackets into the wood of the wall studs. You'll need one bracket at each end of the rail, and additional brackets spaced a maximum of 32 inches apart. Install the brackets so that the clip that holds the rail is at the height you marked with the pencil. Pre-drill guide holes to make it easier to drive the screws. Lay a carpenter's level across each pair of brackets to make sure the brackets are level.
Install each section of rail onto the brackets by sliding the bracket clip into the slot in the rear of the rail. Connect rail sections together by inserting a connector pin into the holes in the end of one rail section and then sliding the other end of the pin into the hole in the other rail section.
Attach end caps to each side of the completed rail by screwing them into the holes in the ends of the rail.
In some kits, you must thread the holes in the outside ends of the rail in order to screw in the end-caps. Check the manufacturer's instructions to see what size tap you'll need to use. It is also possible to run a rail along an inside corner of a wall; this involves purchasing a curved rail section and bracketing it at each end. Check with the manufacturer of your kit for specific instructions.
Rail brackets must be screwed into wall studs; do not use wall anchors or other hardware to mount these brackets to wall board or plaster. These will not provide enough support for the rail and ladder, and could cause the rail to fall off the wall while in use. Make your height measurements carefully; mounting the rail at the wrong height could prevent the rollers from working properly or may cause the underside of the ladder to rub against the bookshelves.