Banisters give your stairs a finished look, and they're also a safety feature that prevents falls. A handrail, balusters and newel posts make up a banister. The newel posts anchor the handrail and support a considerable amount of weight. Balusters must also support people's weight as they move down the stairs. Over time, the screws and glue holding the components of your banister in place may become worn and the banister becomes loose or wobbly. Fixing a stair banister depends on how the balusters were installed, but it is a task most homeowners can do themselves.
Loose or Wobbly Banisters
Inspect the banister to determine the source of the problem. A loose banister is usually caused by stripped screws or worn glue at the newel post or the balusters.
Pry the trim from the bottom of a loose newel post using a pry bar or the claw end of a hammer. Work carefully to avoid damaging the trim.
Use a screwdriver to tighten the screws that secure the mounting brackets to either side of the newel post.
Remove screws or lag bolts that are stripped. A stripped screw tends to turn continuously when you attempt to tighten it, because the teeth or grooves that cut into the wood are worn.
Replace stripped screws or lag bolts with new ones that are slightly longer, and replace the molding around the newel base.
Remove the screws from loose balusters that are toenailed into place. Toenailed balusters are installed so they butt up against the handrail and are secured with screws.
Drill a new pilot hole, slightly smaller than the diameter of the screw, through the baluster and into the bottom of the rail.
Insert the screw into the new hole and tighten with a screwdriver. Countersink the screw so that it rests below the wood surface and insert a wood plug to hide the screw.
Remove the molding that covers balusters installed with a dovetailed joint. These balusters have an end that is cut to fit into a notched space in the bottom of the rail.
Apply wood glue to the baluster and reseat it into place.
Pry up balusters that are secured with small dowels or wood pins until the bottom pin lifts out of the hole.
Apply a bead of wood glue into the holes in the banister and the stair and replace the baluster.
Leave the glue to dry and check the baluster for tightness. If it still wobbles slightly, insert a screw through the baluster and into the rail, then tighten.
Gaps and Cracks
Hide gaps between the balusters and the rail by cutting a wedge of wood the same size and thickness as the space and gluing it into the gap.
Tap the wedge with a hammer to firmly seat it into the gap.
Let the glue dry, and then drive a screw through the wedge and into the rail to secure it in place.
Fill hairline cracks in balusters with wood glue. Larger cracks, where the baluster has split straight through, cannot be patched and should be replaced with a new baluster.