Ceiling Hung Installation:
For normal medium duty residential shelving applications using 3/4″ thick lumber, the maximum recommended span is 4 feet with up to a 1 foot board overhang. For light loading, a span of 5 feet is permissible. For heavily loaded shelving, a span of 3 feet (or less) or thicker shelving is suggested.
Always be sure to not overload an overhead truss structure for ceiling hung shelving and to not overload a wall structure with wall hung shelving. Click Here for an explanation of shelf board sizing.
(1)Drill 3/16″ Pilot Holes on centers and screw in 5/16″ lag eye screws (2)using a screwdriver as shown. For covered studs (ie: drywall), you will need to locate the studs with a studfinder. In this case, be sure to drill a small (1/16″ or smaller) hole through the drywall 1/2″ on both sides of your target hole location opposite the direction of the stud. This is done to insure that your target hole location is near the center of the stud. If your drill is not aligned with a stud, once you drill through the drywall the drill will just “fall” further into the hole with no resistance. When you have hit a stud, you will feel drilling resistance the entire time…be sure to set the drill bit so that it is at least 1″ long from the chuck of the drill.
A quicker and easier method for installing lag eye screws is shown above.  Slip the eye portion into a 1-1/8″ 6 point hex socket and  use a ratchet as shown or an appropriate power tool to tighten. This method is especially beneficial near wall edges and tight corners. A cordless impact wrench will install the lag eye screw within seconds! If using one, be sure to keep one hand loosely around the socket to keep the lag eye screw going in straight. Regardless of how you install, always screw the lag eye screws in as far as you can with your bare hand prior to using any type of tool.
[#5] Hook shelf hangers through lag eye screws and place shelf board across shelf hangers. If shelf boards are bowed, be sure to have the bow up (at center) so that it will achieve a more flattened state once loaded with objects. Hanger clips should be installed (not shown in pic #5) prior to continuing with the next board [See #6 below]. Note that it is OK for the top horizontal row of shelf hangers to tow-in or tow-out up to an inch. It is important that all shelf boards have the hanger clips installed the same distance from the outer side of the shelf board for any given vertical column of shelf hangers. Continue hanging shelf hangers, laying boards, and installing clips until reaching the desired number of shelves.
It is permissible to hang 2 shelf hanger columns from the same pair of eye screws and tow-in the top shelf hangers in order to create a long shelf board from 2 separate shelf boards (ie: seam of 2 boards will be between the 2 columns of shelf hangers – sharing the same pair of lag eye screws). If you do this be sure to keep both hooks on one shelf hanger to the inside and both hooks on the other shelf hanger to the outside so that the boards will stay flush at the front and rear. Additionally, if you choose to toe-in the top shelf hangers, keep in mind that the other end of the board will need to toe-in symmetrically (at least, once installed, the shelf hangers will reside with a symmetrical toe-in)….so plan on spacing the hanger clip centers accordingly.
You may even want to skip a shelf board to double the height of a shelf….or perhaps use 2 different height shelf hangers (skipping a shelf board) to create a specific desired height.
[#6] Hanger clips should be used to fasten the shelf hanger to the bottom of the shelf board. All shelf boards should have hanger clips installed. Two hanger clips should be used with ¾” screws (about 2” away from the front of the board and about 2” away from the back of the board). Installing hanger clips near the center of the board can result in the shelf hanger wire popping it out when heavily loaded. Make sure to maintain same distance from hanger clips to the side end of the shelf board for all boards in any given vertical column. Hanger clips are not necessary for the center column/s of shelf hangers on a 3 column or 4 column shelving unit.
As a helpful suggestion, prior to laying shelf board, install hanger clips with board flat on floor and back screws out enough so that clips are still installed but loose enough to go around wire. This will make it easier to tighten the screws from underneath when laying shelf boards.
Wall Hung Installation:
Locate wall stud centers for lag screw attachment points. For recommended spans (distance between vertical columns of shelf hangers), see “Ceiling Hung Unit” installation at very top. Drill a 3/16″ pilot hole and attach the wall mount shelf hanger using a 5/16″ lag screw and washer as shown in pic #7. For covered studs (ie: drywall), you will need to locate the studs with a studfinder. In this case, be sure to drill a small (1/16″ or smaller) hole through the drywall 1/2″ on both sides of your target hole location opposite the direction of the stud. This is done to insure that your target hole location is near the center of the stud. If your drill is not aligned with a stud, once you drill through the drywall the drill will just “fall” further into the hole with no resistance. When you have hit a stud, you will feel drilling resistance the entire time…be sure to set the drill bit so that it is at least 1″ long from the chuck of the drill. Be careful to not over tighten the lag screws. As illustrated above, continue hanging shelf hangers, laying boards, and installing clips [See #6 above] until reaching the desired number of shelves.
As a helpful suggestion, leave lag screws loose until top board is on. Once board is in position, push down on it directly over the shelf hanger column with one hand while tightening the lag screw with the other.
[#8] Hanger clips may also be used to fasten the shelf hanger to the wall with the wall mount units (pic #8). Starting with the lowest shelf board, install one pair to the outer-most shelf hangers using 1-1/4” long screws. Repeat for every 2 – 3 shelves. It is recommended (though not required) to install the first pair of wall mount hanger clips as low as possible on the lowest shelf hanger to actually pull downward against the lag screws. Note that the wall studs containing the lag screws will run vertical and, therefore, should also line up with the lower shelf hangers to allow hanger clip attachment to wall stud. Depending upon the exact location of the wall stud, the hanger clip may either need to reside to the inside or outside (pic #8 is outside).