Floating shelves look like magic: a slab of wood sticking out of the wall with nothing holding it up. The trick is a steel bracket hidden inside the board and screwed into the wall framing. You can buy finished floating shelves, but making your own from one thick board costs less, lets you choose the exact length and wood, and is a satisfying first woodworking project. Plan on one afternoon for building and a second day for the finish to dry.
How a Hidden Bracket Works
The most common hidden bracket is a flat steel bar with two to four round rods welded to it, sticking straight out. The bar screws to the wall studs, and the rods slide into holes drilled into the back edge of the shelf. The rods carry the load, so they need enough wood around them. That is why floating shelves are thick: you want at least 1-1/2 inches of thickness for 1/2-inch rods, which leaves 1/2 inch of wood above and below each hole.
Brackets come in lengths from about 16 to 48 inches with rods 5 to 8 inches long, and they typically cost $20 to $45. Choose rods about 1 inch shorter than the depth of your shelf.
What You'll Need
Materials
- One board, 1-1/2 inches thick, at least 1 inch longer than you want the finished shelf. A kiln-dried 2×8 (actual size 1-1/2 by 7-1/4 inches) is the budget choice; 8/4 hardwood such as oak, walnut, or maple planed to 1-1/2 inches looks more refined
- A hidden floating shelf bracket sized for your shelf
- Lag screws or structural screws, usually 5/16 by 3 inches, if not supplied
- Wood filler, stain or oil, and a clear topcoat
- Sandpaper in 80, 120, 180, and 220 grit
Tools
- Circular saw or miter saw
- Drill/driver and a brad-point or spade bit matching the rod diameter
- Drill guide or a scrap-wood jig (explained below)
- Stud finder, 4-foot level, tape measure, and pencil
- Random-orbit sander
- Clamps
- Safety glasses, hearing protection, and a dust mask
Step 1: Pick and Check the Board
Sight down the board from one end. You want it straight, flat, and without a twist. Avoid big knots near where the rods will go, and skip boards with deep cracks at the ends. With construction lumber like a 2×8, choose the driest, straightest piece in the stack; wet lumber can warp after you bring it inside. Let any board sit in the room where it will hang for two or three days before you cut it.
Step 2: Locate the Studs and Plan the Length
Use a stud finder to mark the studs where the shelf will go. In most American homes they sit 16 inches apart, center to center. Confirm each one by driving a thin finish nail through the drywall where the bracket will cover the hole.
Your bracket should hit at least two studs. That means a shelf of about 24 inches or longer for typical framing. A shelf can extend past the studs on both ends, but avoid an overhang longer than about a quarter of the shelf on each side.
Also check for hidden wiring and plumbing. Do not drill directly above or below outlets and switches, where cables run vertically, or behind sinks.
Step 3: Cut to Length
Crosscut the board to its final length. Square the ends carefully, since the ends are fully visible on a floating shelf. If you want a more custom look, rip the board to a narrower depth on a table saw, for example 6 inches for a bathroom shelf, but never thinner than 1-1/2 inches.
Saw safety: wear eye and hearing protection, support both ends of the board, keep your hands well clear of the blade path, and let the blade stop fully before lifting.
Step 4: Drill the Rod Holes
This is the step that makes or breaks the project. The holes must be straight, centered in the board's thickness, and match the spacing of the bracket rods exactly.
- Lay the bracket on the back edge of the board and mark the center of each rod.
- Draw a line along the back edge exactly at the midpoint of the thickness, 3/4 inch from each face on a 1-1/2-inch board.
- Drill each hole on that line, about 1/4 inch deeper than the rod length. Wrap painter's tape around the bit as a depth flag.
To keep the drill straight, use a drill guide or make a simple jig: drill a straight hole through a 2×4 scrap on a drill press, or very carefully by hand using a square, then clamp the scrap to the board as a guide. Many builders drill the holes 1/32 inch larger than the rod, so a 17/32-inch bit for 1/2-inch rods, to give a little wiggle room.
Back the bit out every inch or so to clear chips; a long hole packed with sawdust will wander.
Step 5: Test Fit
Slide the board onto the bracket on your workbench before finishing anything. It should go on with firm hand pressure. If one hole is slightly off, ream it with the bit or a round file until the board slides on cleanly. A shelf that has to be hammered onto the bracket is likely to split.
Step 6: Sand and Finish
Ease every sharp edge slightly. Sand the faces and ends with 80 grit to remove mill marks, then work through 120, 180, and 220. The end grain on the two ends absorbs stain more heavily, so sand those a grit or two finer.
Wipe off the dust and apply your finish:
- Stain plus water-based polyurethane: stain, let dry per the label (typically 4 to 8 hours), then apply three thin coats of poly, sanding lightly with 320 grit between coats. Water-based poly is usually recoatable in 2 to 4 hours.
- Hardwood oil: a penetrating oil finish on walnut or oak looks natural and is easy to touch up. Apply, wait 10 to 15 minutes, wipe off all excess, and repeat after 24 hours.
Finish the back edge and the inside of the holes lightly too, so the board absorbs moisture evenly and stays flat.
Lay oily rags flat outside to dry or seal them in a metal can of water. Oil-soaked rags can spontaneously combust.
Step 7: Mount the Bracket
Hold the bracket against the wall, place a level on top, and mark the screw holes at the studs. Drill pilot holes about 3/16 inch for 5/16-inch lag screws, then drive the screws until snug. Check level again before the final turns. If the bracket rocks against an uneven wall, a thin shim behind it will stop the wobble.
Before sliding the shelf on, check that the rods point straight out. Hold a square against the wall and a rod; if they droop, many brackets let you shim the bottom of the plate slightly so the rods tilt up a degree. Under load, the shelf will settle to level.
Step 8: Slide On the Shelf
Push the shelf onto the rods until it sits tight to the wall. Many builders add a small bead of construction adhesive in each hole first, or drive one short screw down through the top of the shelf into a rod hole where a decor item will hide it. Either keeps the shelf from sliding forward over time.
Tips
- Paint the wall before you install. Touching up around a mounted shelf is a hassle.
- Mount shelves a minimum of 12 inches apart vertically for books and 15 inches for taller decor.
- Load capacity depends on the bracket, the studs, and the board. A well-installed 24-inch shelf on two studs commonly handles 30 to 50 pounds; check the bracket maker's rating and stay below it.
- Plaster walls and masonry need different fasteners. Use masonry sleeve anchors for brick and drill through plaster slowly with a masonry bit to avoid cracking.
- Avoid using hollow-wall anchors alone. They are not designed for the leverage a floating shelf puts on the wall.
With one shelf done, building a matched pair or a set of three staggered across a wall goes much faster, since you already have the jig and the hang of drilling straight holes.
