Find the wall studs with a stud finder, mark them, level the shelf and drive 3 in screws through the back rail into at least two studs, two screws per stud.
A shelf is only as strong as what holds it to the wall. Screws into wall studs carry load; drywall alone does not. Here is how to find the studs and hang a ledge or floating shelf safely.
What you need
- A stud finder
- A level and a pencil
- A drill/driver and a bit for pilot holes
- 3 in wood screws (two per stud)
- Painter’s tape and a tape measure
Step by step
- Find the studs. Run the stud finder along the wall and mark both edges of each stud with tape. In many US homes studs are 16 in apart from center to center, and sometimes 24 in. Confirm with a second pass, and with a tap to hear the difference between hollow and solid.
- Check for wires and pipes. Before you drill, make sure there is nothing in the way. Many stud finders can detect live wires, but a finder is not a guarantee. Stay away from outlets and switches, and be careful on walls that share a bathroom or kitchen.
- Mark the height and use a level to draw a straight line across the wall where the back of the shelf will sit.
- Hold the shelf against the line, level it and mark where the screws will go, centered on the studs.
- Drill pilot holes through the back rail of the shelf, so the wood does not split.
- Drive the screws into the studs. Use at least four screws in total, two per stud.
- Check again with the level before the last screws are tight.
How long should the screws be?
You want the screw to go well into the stud. A 3 in screw passing through a 3/4 in back rail and 1/2 in drywall leaves about 1 3/4 in in the stud, which is plenty for a light shelf. Use the real thickness of your board: a 1x4 is 3/4 in thick (see the lumber chart).
What if the studs do not line up?
Drywall anchors are not reliable for carrying load. If you cannot reach two studs, use a shorter shelf that does, or use anchors rated for the weight and keep the load light. Never rely on a single screw into drywall for something heavy.
How much weight can it hold?
That depends on the wood, the screws and the studs. A decorative shelf is for light loads such as picture frames and small plants. If you want to store heavy books or tools, use a stronger bracket system and screw into studs.
A free ledge shelf plan
Our Box Ledge Shelf is a hollow ledge shelf that mounts to wall studs. It measures 36 in wide, 7 1/4 in deep and 4 1/4 in tall (914 x 184 x 108 mm), uses two boards and includes a Square Check so the box comes out square. Download the free plan. Our plans are modeled and checked in 3D and have not yet been built and tested.
Frequently asked questions
How far apart are wall studs?
In many US homes studs are 16 inches apart from center to center, and sometimes 24 inches. Always check with a stud finder.
What screws should I use to hang a shelf on studs?
A 3 inch wood screw is common for a 3/4 inch back rail on 1/2 inch drywall, which leaves about 1 3/4 inches in the stud.
Can I hang a shelf on drywall without studs?
Drywall anchors are not reliable for carrying load. Use studs, or use anchors rated for the weight and keep the load light.
How many screws do I need to hang a shelf?
At least four in total, two per stud, and screw into at least two studs.
Build the shelf, free
Download the Box Ledge Shelf plan: two boards, five parts, a cutting diagram and a Square Check, ready to hang on studs.
Get the free plan