What you need to know before you start
Stair spindles—the vertical balusters that run between your handrail and the stair treads—can be replaced without removing the entire railing system. Most spindles are either screwed or glued into place at the top and bottom, or both. The job takes a few hours and requires basic tools: a drill, a reciprocating saw or handsaw, a chisel, sandpaper, and wood filler. The hardest part is usually getting the old spindle out cleanly without damaging the handrail or newel post it's attached to.
Before you start, measure the spindle you're replacing—length, diameter, and the depth of the holes it sits in. Take a photo of how it connects at the top and bottom. If your spindles are decorative turnings (the fancy spiral kind), you'll need to order a matching replacement, which can take one to two weeks. If they're straightforward dowels or square balusters, you can often find stock sizes at a home center the same day.
Key Takeaways
- Most spindles are held by screws or dowels at the top and bottom; you'll need to remove or cut these before the spindle comes free.
- Measure the old spindle's length, diameter, and hole depth before ordering a replacement, and bring a photo of the connection style.
- Use a reciprocating saw or handsaw to cut spindles that are glued in place, then chisel out the remaining stub and clean the holes.
- Sand the new spindle lightly and test-fit it before gluing or screwing it in place to make sure it sits flush with the handrail.
- If the holes are enlarged or damaged, use wooden dowels and epoxy to rebuild them before installing the new spindle.
Removing the old spindle
Start by examining how the spindle is fastened. Look underneath the handrail and on top of the tread for screws—these are the easiest to remove. Unscrew them and pull the spindle straight out. If there are no visible screws, the spindle is likely glued into holes drilled at the top and bottom.
For a glued spindle, use a reciprocating saw with a metal-cutting blade or a fine-toothed handsaw to cut the spindle in half, roughly in the middle. This gives you two shorter pieces that are easier to wiggle and remove. Once you've cut through, work each piece side to side to break the glue bond, then pull it out. You may need to tap gently with a hammer on the side of the piece to loosen it.
After the spindle is out, you'll have a stub of wood left in each hole. Use a chisel slightly smaller than the hole diameter to carefully chip out the remaining wood. Work slowly and angle the chisel to avoid splitting the handrail or tread. Once the hole is clear, sand it smooth with medium-grit sandpaper (120 to 150 grit) to remove any glue residue.
Measuring and ordering the replacement
Measure the spindle from the inside of the hole at the top to the inside of the hole at the bottom. This is the length you need. Measure the diameter of the spindle itself and the depth of the holes it sits in—usually 1 to 1.5 inches deep. Write these numbers down and take a clear photo of the spindle's profile and how it connects.
If your spindles are plain dowels or square balusters, you can often find replacements at a home center or online lumber supplier. If they're decorative turnings, you may need to order from a specialty stair parts supplier or a local woodworker who can turn a matching piece. Bring your measurements and photo to the supplier; they can usually match the style and size within a day or two, though custom turnings may take longer. Buy the replacement spindle slightly longer than your measurement—you can sand it down to fit. Also pick up a bottle of waterproof wood glue and some 120-grit sandpaper if you don't have them on hand.
Preparing the new spindle and holes
Before installation, sand the new spindle lightly with 120-grit sandpaper to smooth any rough spots and help the glue bond better. Pay special attention to the ends that will sit in the holes. Wipe away all dust with a damp cloth and let it dry.
Check the holes in the handrail and tread. If they're clean and the right size, you're ready to install. If a hole is enlarged, damaged, or the wood is soft, you'll need to rebuild it. Drill out the hole to a larger diameter (usually 1/2 inch), then glue in a wooden dowel of that size using epoxy. Let it cure fully—usually 24 hours—then drill a new hole in the dowel to match your spindle's diameter. This gives you a solid anchor point.
Installing the new spindle
Test-fit the spindle in the holes without glue first. It should slide in smoothly and sit flush with both the handrail and the tread. If it's too tight, sand the ends slightly. If it's too loose, the glue will hold it, but a snug fit is better. Once you're satisfied with the fit, remove the spindle.
explore waterproof wood glue to both holes—not to the spindle itself. Use a small brush or the applicator tip on the glue bottle to coat the inside of each hole evenly. Slide the spindle in and push it firmly into place. Wipe away excess glue with a damp cloth when ready. If the spindle was originally screwed in place, drill pilot holes (smaller holes to guide the screw) through the handrail and tread into the spindle, then drive the screws home. Countersink the screw heads slightly and fill with wood filler if you want a finished look. Let the glue cure for 24 hours before putting weight on the railing.
Finishing and checking your work
Once the glue has cured, sand any rough spots where the new spindle meets the handrail or tread. If you used wood filler over screw heads, sand it flush with 120-grit paper, then 220-grit for a smooth finish. Wipe the area clean.
If the spindle is stained or finished to match the rest of the railing, you may need to stain or paint the new one. Test the stain on a hidden area first to make sure the color matches. explore stain or paint according to the product instructions, and let it dry fully before using the stairs. Give the spindle a firm push and wiggle test—it should not move. If it does, the glue may not have set fully, or the hole may need rebuilding. Wait another 24 hours and test again.
When to call a professional
If the handrail or tread is cracked or splintered around the spindle holes, or if multiple spindles are loose or damaged, the underlying structure may be compromised. A carpenter or stair specialist can assess whether the railing is still safe and repair or reinforce it if needed.
If you're uncomfortable using a saw or chisel, or if the spindle is part of a curved or spiral staircase, a professional can do the work faster and with less risk of damage. Metal or wrought-iron spindles are bolted or welded in place and require a welder or metal fabricator to replace safely.
Frequently Asked Questions
Can I replace just one spindle, or do I have to replace them all?
You can replace a single spindle. However, if the new spindle is a different shade or finish than the old ones, it may stand out until it weathers to match. If multiple spindles are damaged or loose, replacing them all at once gives a more uniform appearance.
What if the spindle hole is stripped or enlarged?
Drill the hole out to a larger standard size (usually 1/2 inch), glue in a wooden dowel of that size using epoxy, let it cure fully, then drill a new hole in the dowel for your spindle. This rebuilds the anchor point and is stronger than trying to fill a stripped hole.
Do I have to glue the spindle, or can I just screw it?
Screws alone can work, but glue plus screws is stronger and more durable. If the original spindle was only glued, glue the replacement. If it was screwed, you can screw the new one, but adding glue as well will make it last longer.
How long does the glue take to set?
Most waterproof wood glues set to the touch in 30 minutes to an hour, but they need 24 hours to cure fully. Don't put weight on the railing or use the stairs heavily until the glue has cured completely.