How can I improve the appearance of these unsightly gaps in the stair trim without having to replace it, especially when some are nearly an inch wide and the trim was poorly cut?
Asked by Helena Skotte 
2 months ago
Last Updated: November 1, 2024
I’m trying to figure out how to make these gaps in the stair trim look better without having to replace it. Some of the gaps are almost an inch wide. The stairs themselves are fine, it’s just that the trim was poorly cut and isn’t the original.
You might want to figure out why your stairs have sagged so much.
Hey , it’s not sagging. This is not the original trim, just a poorly done cut. You can notice where they filled in with caulk.
Are you pointing out the caulk as evidence that the trim board is not original?
I used to be. If you want, I can snap a photo of the other half of the stairs that still has the original design.
Still looking good, no sagging.
Okay, so make sure to closely match the design on this side when fixing the other side, otherwise the stairs won’t look good. It’s good that you have a clear goal in mind. It will require the skill of a finish carpenter, or else a lot of time for trial and error.
‘s work will be tough to replicate – it’s over a century old. The top half of the stairs still has the original trim, but the bottom half has been changed. I think they removed the trim when they added wood paneling to the walls by the stairs. This project is definitely beyond my abilities, but I’m planning to hire someone for the crown molding in the dining room, so I can ask them about the stairs then.
: That sounds like a great plan! I think it might be better to look for a carpenter who can closely match the original stair skirt details, even if it’s not the exact moulding contour. That way, they can handle the crown moulding as well. I’d be worried about hiring someone who only does crown moulding and isn’t familiar with old stair skirting and trim, since there are probably more options in that category.
Thank you, !
It looks like those stairs require additional support – they have old dado stringers and the treads and risers are being held in place with a wedge/shim.
You can use caulk or spackle to fill in the gaps, and then paint over the exposed areas in white or black to give it a deliberate design element.
I was actually thinking the same thing, .
Mentioned that using the steps will make their ends move slightly. You might notice some cracking where the mud meets the wood.
Just paint it the same color as the step and call it a day.
I totally agree with the other person, your stairs have definitely been shifting! Figure out the cause and fix that issue, and the gap should disappear =)
You should definitely investigate why your stairs are moving away from the stringer. Make sure there are wedges behind the risers and treads. ‘t just fill the gap. Use a level on the stair treads and risers to check if they are still even. Determine if the stairs are sagging or if the stringer is shifting (maybe it’s attached to a foundation wall that’s moving?). Those treads could be unsafe to walk on depending on how much they have moved away from the stringer.
The stairs themselves are perfectly level. No issues with that. It’s just the poor quality of the trim that was added. It’s not the original trim.
Hey if you’re sure it’s just cosmetic, here are a few options to consider;
1. Fill with body filler, sand, and paint,
2. Fill with hot mud, sand, and paint,
3. Create a new stringer cover/trim as suggested by another member.
4. Take out what they put there, check what’s behind it, and it might be simpler to finish what’s there and end up with a slightly wider step.
5. Remove the existing trim, use it as a guide to make a new one, but before removal, note down all the gap sizes for each step to ensure the new one is larger in those areas.
You really should take a look under the stairs. There’s an issue that will only worsen over time. It might be easier to fix than you think with some jacking and additional support.
Stairs are in good condition. The trim was just poorly cut.
After numerous failed attempts, here’s how I finally got it done.
Kevin s I’m worried I might not do as good a job as they did. 😅
If that’s the original skirt board, your stairs might be sagging and you should deal with it. If it’s a new board, it’s poorly done and a skilled carpenter should replace it properly. I remember seeing an interesting patchwork technique here that could work if it’s just going to be painted, but it’s not the best long-term solution.
Remove the stringers and create new ones using cherry or pine. For a more premium look, consider purchasing a 4’×8’×5/8″ oak sheet to create a high-quality set.
Those are for sure not stringers. They are known as skirt boards. Stringers are below providing support for the treads.
Oops I misspoke haha. Traditional style. Some stringers have treads built into them
Wow, that’s super old, . I’ve come across a few and they’re quite intriguing.
I’m still loving my stringer and putting in treads, .
Write down some new lines, delete them, and insert them where needed
So in our home, we have stairs with no stringers. It’s not a big deal. What if we just take out the badly cut ones and touch up the visible section? There might be some minor cosmetic flaws, but how bad could it really get?
Perhaps in the future, if you decide to renovate or feel like getting creative, putting in stringers could work out.
If you’re certain the stairs aren’t sagging, consider replacing the wall stringer. Alternatively, you can keep the existing wall stringer, purchase the thinnest plywood available (1/8-1/4) from the big box store, and add a properly scribed cut layer to the face of the poorly cut stringer.
It’s a great suggestion to create a template and secure the plywood in place
Footwear
It’s probably best to bring in a professional carpenter to get it done correctly.
Just to let you know, the skirt boards were poorly made.
Oh wow! There are definitely more areas in this house that were poorly done. 😂
There is a gap under the shirt. Remove the skirt and place a 1×10 or 1×12 board behind it. No need to cut out for the treads…
It’s challenging to determine what part of the treads is original and what was added later on the unstained section… It seems like everything was part of the original design, but it would be interesting to find out what was previously covering the gap. Unless those treads were taken from another staircase…?
Hey , it seems like the original skirting was taken off when they installed wall paneling over the plaster walls above the stairs. This is the unaltered upper portion of the stairs.
Is that the same side as the picture in your post? Are you implying that the skirt in the picture on your post was taken off and that the one in the picture was new and freshly cut?
The skirt just seems a bit outdated to me, but it looks like there is enough space to add a 1x trim behind it. You could also consider using 5/8 cabinet grade plywood if the 1x is too thick.
Make sure your stringers are holding up the tread weight correctly.
Can’t fit it in because the treads would get in the way. They fit snugly under the existing trim and have been in place for over a century.
It seems like the riser in the original picture might need to be adjusted, while the top 2 steps show the tread and bull nose butting up to the skirt. It’s hard to say for sure with just this one picture. If someone cuts a new skirt, have them come and make the adjustment. It’s a tricky cut to make, even with a compass scribe, and should be done in 2 pieces.
Yeah, that was also my initial idea, to slide the trim behind it. The cutting is beyond my skill level, which is why I asked for suggestions on how to improve the look for now.
Is looking better at the moment, an easy short-term solution… Lift the edges. Apply spray foam, carefully trim excess with a razor, then fill with spackle, sand, caulk, and paint.
If you prefer not to use wood for replacement, fill larger holes with caulk backer rod and use Bondi or a similar type of filler. Remember to tape off the stairs and apply thin coats to gradually build up. Sand until smooth, prime, and paint. When applied correctly, Bondo will provide a solid finish.
Consider replacing the drywall altogether.
I typically install the skirt before the treads and risers.
So this piece was trimmed to fit perfectly. It hid the gap.
This is the moulding for the door stop. It is nailed flat onto the skirt.
Consider adding quarter round trim!
Fill in the gaps, then sand and paint over them.
Make sure to tape it up securely and grab a gallon of Bondo to fill it in smoothly. Take your time using a putty knife to fill it in and then sand and repaint.
Put in a new side stringer
The stairs are starting to sag a bit. The skirt board has been carved out to fit the treads and risers, but it stayed in place when the treads and risers shifted because it’s secured to the wall.
I see what you’re saying about the stairs not sagging, but when I zoom in, I notice a dadoed or plowed stringer. The treads used to touch the top of that gap. I’m not sure why the other side is still snug. Do you have a view of the back of the stairs?
You should definitely request a redo. That work is pretty disappointing.
Personally, I’d go with bondo. It sands really smoothly and flush, making the gaps practically invisible.