A shelf that pulls slowly out of a plasterboard wall, taking a chunk of the wall with it, is one of DIY's classic disappointments. The board itself holds almost nothing on its own, so the whole job comes down to using the right fixings.
Find the studs first
Plasterboard is fixed to a frame of vertical timber or metal studs, usually spaced around four hundred millimetres apart. Anything screwed straight into a stud is rock solid, so an inexpensive stud detector is the best place to start.
Fixing into the board itself
Where there is no stud, you must spread the load with a proper cavity fixing. The cheap plastic plugs sold for masonry are useless here and simply spin in the hole.
- Spring toggles or metal anchors for heavier loads.
- Self-drive nylon anchors for lighter ones.
- Never rely on a bare screw in plasterboard.
Mark and drill carefully
Hold the bracket up, check it with a spirit level, and mark the holes with a pencil. Drill the right size hole for your chosen fixing, neither so tight it crumbles the board nor so loose the anchor pulls through.
Think about the load
Be honest about what is going on the shelf. A row of paperbacks is one thing, a stack of hardbacks or a row of mugs quite another. For anything heavy, fix at least one bracket into a stud, and the shelf will outlast the room's decoration.