It’s too late to do *anything* meaningful for noise modulation at this point, unless you want to be invasive. You can stuff it full of whatever, if it makes you feel better. Or rip off the drywall on the common wall and foam it, then add a second drywall layer in the bath and bed.

Youll end up wanting a runner just from the lack of traction slipperiness aspect of a wood stairs. Might as well plan on it now.

If you stuff you very well may inhibit the treads from being installed properly as they need to get to the underside typically to finish the install.

You're going to need that runner, I know you said you're not interested, but you're going to need it. Not only for noise reduction, but as mentioned in the earlier comment, for traction. Also if you have pets, for them too.

ETA: the white-painted stair risers, without a runner, will show scuffs quickly.

Thank you for the advice and comments. And I did not realize that treads are accessed from the underside. I had planned to ask my builder about this, but since it's the weekend, I was waiting until Monday.

The stairs are not near the bedroom as one of you mentioned, so no problem there. It's on the same wall as our bathroom and my DH's closet.

I failed to mentioned that I think most of the noise that I heard the other day was because I was standing near an area underneath the stairs that is connected to our water closet area. There will be a door to that area underneath the stairs. And the main part of the bathroom will be another 7' away from this wall divided by another wall and a privacy door. So with the divisions, and nice red oak treads, I hope the noise is not too bad. Then I'll hope that floor and wall furnishings will help with the echo.

Thankfully, we do not have children living in the house that will be running up and down the stairs everyday. We will have grandchildren visits, and occasional guest. We do have a dog, but she does not like to do the stairs, anymore, whether they are carpeted or not. We are currently in a rental that has carpeted stairs. NOPE!!! In our previous home, she ran up and down all 3 flights and did just fine. She is getting older at 6yrs.

Finally, all of our past homes have had all wooden staircases that are opened to other areas. We love them! No huge problem with scuff marks, either! This is just the first that it has been connected to a privacy area. We will not rule out a runner for the future as DH and I age. 😉

Stand on the stairs and have your husband use the bathroom (if you know what I mean) and see if you can hear him plain as day. I think what you hear on the stairs is more important than what you can hear in the bathroom or closet.

Interesting. I have wood stairs, white risers, and no runner. Similar look and it borders a closet and then bathroom. I don't have any noise issue and I don't have significant issues with scuffs (although it is an issue, just not a significant one). I think I painted out of pure OCD ness at the 2 year mark but it was not noticeable by anyone but me. And it took me less than an hour.

When we were building, we insulated the entire house including all interior walls and steps. I have no clue if it makes a difference, but from what I understand, what‘s actually needed for proper soundproofing is air space in between the insulation and the adjoining room and then insulation in those walls…..kind of like a sandwich of insulation with air space in between. I’m not an expert, but that’s what I gleaned from researching (although I do think insulation alone must help to muffle the sound some).

It’s virtually impossible to make a judgement as to how noisy things will be at this point if your house is still under construction and empty….every sound is magnified when there’s nothing in the house. Upholstery, rugs, drapes, etc. absorb a lot of noise.

We have no runner on our stairs, but then we walk around the house barefoot so there’s not much sound made without shoes on. Part of my husbands study is on the other side of the stairway and he’s never mentioned anything about being bothered by noise coming from the steps and he does a lot of live radio interviews so needs things pretty quiet.

Love your front door BTW!

Speakeasy door needs a grille. (And bulletproofing.)

worthy - There is a grill on the outside. ;)

Mark Bischak, Architect - Interesting suggestion that I will be sure to test out when there is a toilet installed. As I mentioned before, there is Rockwool in the wall on two sides of the toilet area. I've attached some photos of the area to better understand where I was when hearing the noise. The door was open with the underneath area of the staircase exposed.

David Cary - I know what you mean about the OCD. Although with our previous staircase, I think I may have had one mark on the first riser that was cleaned off in 14 years. They were all wiped occasionally by my housecleaner. Glad that you also like your treads uncovered. ;)

nidnay - We put Rockwool in many interior walls, and foam in some others (like between our great room T.V. wall and our dining room.) The outside walls are all foam.

In our previous home, our stairs ran along the same wall as my study. Husband had an office upstairs. I could certainly hear him when he was walking up (to his office) or down (to the basement.) The noise was not bad at all, nor did it echo. We had no insulation in that wall. So hoping that once we get settled, the noise will be a non issue. I would still like to do something in the stairs. What did you use for your stairs?

Photo of stair cavity - That's sheetrock you see on the bottom.

I was standing at this sink when DH went up the steps talking loudly to himself. See the stair slope through the 2nd doorway. Underneath the stairs is a place to store luggage.

A closer view taken from the sink. There will be a full mirror on the door leading underneath the stairs. The room forward of the mirrored door (behind this first door that you see) is the water closet with toilet over to the left and set back about 3'.

On the opposite side of the wall next to the toilet (toilet goes where you see this little table) is a tiled shower for a guest bathroom. The shower is also under the stairs. That wall has the Rockwool, as does the wall you see on the outer side of the slope wall that faces the foyer.

Sketch that I made showing layout.

UPDATE: Met with builder today. He listened from the bathroom and agreed that it sounded echo-y. Also assured me that the sound will be more muffled when all is said and done. Plus, he said it would not hurt to try some insulation in the stair cavities and it would be no problem doing so.

nidnay - 😉 Would love to know what was used in your stairs?

There are numerous academic studies showing that IIC and STC are very little attenuated by fibreglass and rockwool. (And the few times I've used it the results have been similar.) But it seems that it should work, so builders and homeowners persist in stuffing it everywhere. Simply not wearing shoes indoors trumps insulation every time! (Still an Ontario thing, I find.)

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Note the varying STC of a typical 2x4 @ 16" o.c. gypsum board wall using adhesive instead of screws and one with 2" sound attenuation batts but attached with screws: NIL. (The results are in the details.)

The sound of footsteps on the stairs is structure borne so insulation will not help much if at all. Where the stair enclosure is exposed in the closet or in the shower, the sound transfer can be reduced with a layer of QuietRock drywall or a layer of drywall on resilient channels or hat channels attached by acoustic isolation clips or drywall over GreenGlue. You could also add sound gaskets to the closet door at all 4 edges assuming it's a solid core door.

Sound Insulation Class (STC) measures the level of airborne-sound isiolation between two spaces.

Impact Insulation Class (IIC), measures the level of structure-borne sound isolation between two spaces.

Insulation can help with the IIC rating if there is a cavity involved but otherwise decoupling with the above mentioned materials and systems is necessary if adding a cusioned walking surface material is not acceptable.

Builder put Rockwool inside the staircase cavities. Treads are on (the staircase seems so solid now) and the echo has disappeared. Not sure if the Rockwool helped, or if it was simply from putting the threads on... plus the wainscoting on stair wall, but I am very pleased!!!

"Very pleased!" is the key. Now the kids can sneak in and out without waking you with squeaky stairs.