Wooden spiral stairs are not easily damaged, but when they are it is important to repair them immediately. Depending on which part has been damaged, it could be a very easy fix, or a very complicated one. You can use this article to help determine what needs to be replaced and how to do so.
Step 1- Diagnose the Damage
In this step, you will look over your spiral stair and determine just how much damage has occurred. This may seem straightforward, but you need to examine the surrounding pieces as well to make sure that you fix every issue. If you have a broken baluster, you need to make sure that the handrail has not also been damaged. If you have a damaged tread, you need to make sure your balusters are still in good shape. You also need to check any damaged newel posts (the posts that connect each stair to the one above it), and see if it has damaged the treads connected to them. Once you have an idea of what needs to be repaired, we will move on to the actual repair process.
Step 2 - Repair a Damaged Baluster
If your baluster is just loose, most modern spiral stairs have balusters attached with screws. Simply tighten the screws to solve the problem. If it is not screwed, you can fix a loose baluster by inserting a wood shim along with some glue where the baluster meets the tread. If your baluster has been damaged, remove it completely by either unscrewing it, or cutting it out using a saw.
If your spiral stair was a kit, you can contact the manufacturer for a replacement that exactly matches the rest of your balusters. If you do not know how your spiral stair was made, you can try to search online for a baluster that closely matches the one you have, employ someone with woodworking skills to copy your old one, or consider changing out several balusters to make an alternating pattern. Simply install the new one by wiggling it in top first and screwing it back into place.
Step 3 - Replace a Damaged Newel Post
Replacing a newel post is similar to replacing a baluster, but with one major difference. Since a newel post connects two steps together, you need to replace it exactly to make sure it will still fit through both holes of the treads it connects. If you can order a replacement from the manufacturer, you should. If not, it would be worth the investment to have someone fabricate the exact piece you need by copying the old damaged newel post. Make sure that the treads have not also been damaged along with the newel post, because they are the most difficult part to repair on a spiral stair. Once again, like balusters, the newel posts will most likely be screwed in. Simply screw the new newel post back into place.
Step 4 - Replace a Damaged Tread
A wood spiral stair tread is the most difficult piece to replace. If you did happen to buy your stairs as a kit, buying a replacement tread will be the easy part. The difficult part is that you have to disassemble the stairs by removing the handrail, balusters, and each tread and spacers until you get down to the broken tread. If more than one tread is damaged, or there are other issues with your spiral stair, you may want to go ahead and purchase a new kit. It will be about the same amount of labor and you won't have to worry about it for many years.
If your stairs are not a kit, you still have a few options. If your wood tread has a metal base, you can just remove the wood part and buy replacement wood that you can shape with a table saw. If the tread is nailed or screwed directly into the center pole, you can unscrew it and then again use replacement wood. Unfortunately, if your stairs have a hole cut into the tread and it was then dropped into place on the center pole, you will need to disassemble the entire stair to replace the single damaged tread.