Will a Magnet Work Through Wood, Drywall, Glass or Fabric?
Yes. Wood, drywall, glass, plastic and fabric don’t block a magnetic field, but their thickness acts as an air gap and holding power drops fast. Through 1/2 inch drywall, a 1 × 1/2 Inch N52 disc keeps only about 4% of its 54.5 lb rating against a steel plate. Put a second magnet on the other side instead and the pair holds about 15%. For thick panels, use bigger magnets, magnet pairs, or set the magnets into the surface.
Does the Material Matter?
Not for non-magnetic materials. Wood, glass, drywall, plastic, fabric, paper, aluminum and most stainless steel all let the field through as if they were air, so only the thickness counts. Iron and steel are different: they pull the field into themselves, which is how steel shielding works.
Estimated Holding Power Through Common Materials
Straight pull for a pair of identical N52 magnets, one on each side, from our magnetic model:
| Material and typical thickness | 1/2 × 1/8 Inch | 1 × 1/4 Inch | 1 × 1/2 Inch | 2 × 1/2 Inch |
|---|---|---|---|---|
| Felt, cardboard or heavy fabric, 1/16 in | 3.5 lb | 20 lb | 37 lb | 97 lb |
| Acrylic, tile or a glass whiteboard, 1/8 in | 2.1 lb | 15 lb | 28 lb | 80 lb |
| Glass shelf or thin plywood, 1/4 in | 0.9 lb | 8.6 lb | 18 lb | 57 lb |
| Drywall, 1/2 in | 0.2 lb | 3.7 lb | 8.1 lb | 34 lb |
| Cabinet door or plywood, 3/4 in | 0.1 lb | 1.8 lb | 4.1 lb | 22 lb |
With a thick steel plate on the far side instead of a second magnet, expect less: about 80% of these numbers through thin layers, falling to 10 to 20% for small magnets through thick panels. For loads that slide down a wall, divide by about five. These are estimates for perfectly aligned magnets; test with your actual materials.
Why a Pair Beats a Steel Plate
A magnet pulls on a steel plate as if a mirror image of itself were hiding behind the plate’s surface, the same distance back. So a 1/2 in panel acts like a 1 in gap. A second magnet sits only 1/2 in away, which makes a big difference. More in magnet-to-magnet vs magnet-to-steel.
Ways to Work Through a Panel
Recess the Magnet
Drill or route a pocket from the back, leaving 1/16 to 1/8 in of material on the face. Hidden cabinet catches and knife racks work this way.
Clamp Through Glass
A magnet on each side of glass holds ledges, signs and cleaners. See terrarium ledges and glass whiteboards.
Find the Steel Already There
Drywall screws and nails are steel. A strong magnet finds them, and studs, through the wall. See finding wall studs.
Go Bigger, Not Stronger
Through thick panels, a larger or thicker magnet helps far more than a higher grade. Double the size roughly doubles the reach.
Hanging Art on Drywall?
Magnets through 1/2 in drywall rarely hold more than a light poster when the load slides down the wall. Instead, set a flat-head steel nail or screw into the wall and let a small magnet hold the print against it. See hanging art with magnets.