Home condo unit flooring.... Opinions wanted...

Here's what I'm looking to accomplish. I'm on the second floor of a condo (owned, not rented). The place was built 75 years ago and the floors squeak like crazy which drives me nuts. Sound from neighbors below isn't a huge issue, but you can hear them if you sit here quietly. The current flooring is 3/4" subfloor(x6" boards) >3/4" hardwood(x2.1/4" boards) >Carpeting. I brought in a contractor that me and my family have used plenty of times and he's great. He recommended the subfloor needs to be secured to have any chance of having a quiet floor. I don't doubt him, so I started ripping things up. Although I didn't finish pulling up the hardwood yet, the subfloor does move below your feet in certain areas. You can feel it.

Side notes:
-I want to recess the radiator into the wall.
-Having a second floor unit, I'm "supposed" to have fully carpeted floors. Nobody has ever checked though.

That's the basic background, so here's where I'm looking for opinions. What would YOU do....

1. Rip up the subfloor, lay down some insulation or sound proofing and replace with 3/4" plywood sheets then carpet.
2. Rip up the subfloor, don't bother w/ insulating it's not worth the cost and just put down new 3/4" plywood then carpet.
3. Don't get that involved. Put a screw in each of the subfloor boards, hope for the best and lay new 3/4" plywood over it then carpet.
4. Rip up the subfloor, lay down insulation or sound proofing then 3/4" plywood and a new 3/4" hardwood floor. (no carpeting)
5. Rip up the subfloor, don't bother w/ insulating b/c it's not worth the cost, but lay down 3/4" plywood then 3/4" hardwood. (no carpeting).

 

Here's what it looks like under there.....



And yes, that old hardwood was a mess. Could've been refinished, but that really wouldn't accomplish anything I was going after. It wasnt an option.

 

The order I would do it (just finished hardwood flooring @ my cabin this summer) is: 3/4" plywood, sound barrier (insulation?), then hardwood.

 

A couple of questions. Are you done ripping up the hardwoods? How many SF is the room you are rebuilding? I'm guessing once the floor is taken up, you can methodically go by each piece of the subfloor and cherry-pick what subfloor plank needs to be replaced. Since the subfloor is strips instead of whole sheets it may make sense to replace but it may not be necessary. I would use good deck screws to make sure each subfloor plank is in place. I'm not sure you should put insulation under the subfloor in case there's any electrical or other. I would not, however, put carpet down after all that hard work. New hardwood flooring should make things nice and probably a little bit quieter.

 

If you remove the subfloor, where it goes under the walls there may be no support for the walls. Then it also gets difficult to support the new subfloor at the walls as there may not be anything there to the attach the new subfloor to. Big ole can of worms till you know whats under there and how it was built.

 

More and more people are using wood like vinyl flooring for the last layer, tough as hell, easy to take care of and in some cases water proof.

 

Nice work! Turned out great!
The sound barrier type of insulation I was referring to is something like Roxul, or even something basic like the pink itchy stuff. It goes between the joists. Has some fire-resistance to it, so thats a plus? The layer of foam/paper/fabric between the subfloor and hardwood was understood. I know a layer of that should go down, regardless.

The bedroom is approximately 140 sq/ft. I'm not entirely done ripping it up. Halfway there. Only a couple hours of work to get the rest of it up. I've been trying to clean and cut the pieces up as I go to make disposal easier. So thats taking up some time.
If I remember right, the only electrical for the unit below me is a light/ceiling fan in the center of their room.

But like you said, since the current subfloor is boards I'm wondering if it's worth replacing with sheets. I think that's my biggest dilemma right now. Is it going to be worth the extra work in the end to accomplish a quiet floor.

At least along the exterior wall, there is a joist running parralel w/ the wall. The subfloor is nailed to that one and can be secured to it. I snapped a quick picture so you can see.

 

For 140SF, I would replace the subfloor. But like the other poster said, it could be trouble with the walls. I would refer to a contractor who knows how to replace subfloor.

 

Just a few tips:
-Listen to your contractor...he’s been doing it for a living and is someone you and your family trust. And he’s actually looking at the situation up close, not photos.
-Rock wool insulation will give you better sound insulation.
-Subfloor will need better securing...more nails or screws. A layer of sheet subfloor (ply, etc.) will help “tie the room” together if you have space for it (thickness).
-Sound transfer reduction from below will have to come from the addition of mass (Gyp-Crete usually) or a mass-loaded vinyl product ($$). Screws and nails from flooring to framing transfer sound through the system.
-Don’t get in trouble with your association. Construction sounds followed by increase floor noise may prompt the “carpet check” from downstairs neighbors.

 

Yea, I did talk to the downstairs neighbor and told him I'd be working on the floor. So he expects some noise every once in a while. Also why I want to tie everything up sooner than later so it's not prolonged floor noise from the current lack of material quieting things down.

 

Ok. I'm late to the party. You may have completed the work already.

Suggest to remove the hardwood. Keep the current subfloor. Pull the baseboard off, set it aside for install later. GLUE and SCREW 3/4" ply over the current subfloor. Finish with carpet, hardwood....whatever you want. This will raise the floor, so doors and thresholds may need to be adjusted. Install the saved baseboard.

A tips: Use a marker to label the back of the baseboard pieces for their location. The screws need to long enough to pass through the plywood+subfloor+2x thickness of ply+sub. Probably need a 3" screw on 12" centers.

The ply glued-n-screwed will add mass to the current subfloor. The current subfloor wood is 75 years old. It is dry like a popcorn fart. The nails holding the wood to the floor joists have let go. The squeak comes from the wood rubbing on the nail shank as you walk around. The glue will bond the subfloor and plywood together. The screws will anchor the floor system to the floor joists.

Squeaks will disappear and never return.

 

Oh.....a couple more thoughts to consider.

Lay the length of the plywood at 90 degrees to the floor joists. Stagger the ends.
Snap a chalk line to locate the floor joists.
Use a #2 square drive screw. The #2 Phillips heads like to cam out. The square drives don't, until the bit is heavily worn.

Once the hardwood is up, this will be about 1 day to lay the plywood, likely less. Bonus, the work won't be terribly obnoxious for noise.

Material wise:
5-6 sheets of 3/4" x 4' x 8'
2-3 lbs wood screws 3" long with #2 square drive
2-3 #2 square drive bits
4-5 10 oz tubes of Construction Adhesive.

All will fit in your Taco in 1 trip to the Big Box.
Then you have to hump the ply upstairs.......hardest part.

 

Awesome, THanks @Knute ......

Nope, I haven't completed it yet. I'm not planning to do any more until later this week and even then, I'm only planning to do more removal of the current hardwood. I probably won't start reinstalling for at least a week or two after that, between all the other projects I have going on.

Joists are 16" on this floor. Each of the current subfloor boards have 2 nails per piece at each joist. So I'm gonna have to hope I can screw down the plywood in just the right spots. My luck, I'll hit a nail every time

Yea, I was going to ask what adhesive you recommended. A tubed adhesive won't cause high spots? I didn't know if they made something that applies thinner, maybe with a roller or whatever, so that it's an even application. I've used the subfloor adhesive tubes before when I did the bathroom. Pulled the subfloor up entirely in there and glued down new ply to the joists w/ that, plus the screws.

 

Tube adhesive is the way to go.

Lay a 1/4" bead inline with floor joists. Drop the ply on it, bump into place, snap your chalk line to mark the floor joists, screw 'er down. Your walking on it will spread the adhesive. You won't have high spots from the adhesive. Screw 12" on center along the floor joist. Yeah, you'll hit a nail or 4. Another reason for the #2 square bit.

My first house was built in 1866, we bought it in 1994. It had numerous problems. Floors were just one. I learned how to handle without too much trouble. Lathe and plaster was the worst job. Horsehair binder, coal dust, rodent leavings, 1000's of square nails, rough sawn 2x4s of oak (these were actually 2x4)......nothing straight, plumb or level. A real SOB to remodel.

You start yanking subfloor, you can open a whole new can of worms. You don't want to accidentally step through the ceiling below.

 

If the noise from the existing sub-floor is bothering you there is only one way to completely stop it. Pull the entire floor. Glue and nail new 3/4 tongue and groove ply or osb. Then finish with your choice of material.

Insulating the bays will be much appreciated by your downstairs neighbor as it will help absorb some noise. Putting a new laminate floor down with a thick pad would eliminate a lot of noise as well. I personally hate carpet so would do my best to keep the noise down after install.

 

Thought it'd be fun to update this thread. I've been slowly working on it. I'm solo, and with everything else in life getting in the way...this is simply taking a long time. That's ok though. I'm slowly making progress.
I have a plumber coming today to give me a quote on recessing the radiators into the walls to gain a few more inches along the walls and get rid of those crappy looking radiator covers in the bedroom and living room (kitchen can wait til a remodel is done).

So here's what's happened over the past 3 weeks. I've pulled up the carpet and hardwood in the bedroom and hallway. I ultimately opted to pull any loose nails and add an additional screw to the subfloor at each joist. New pine T&G ply over that. It's solid so far! But man, the old hardwood was trashed! Crazy gaps, deformations, paint dripped from who-knows-when.

They missed plenty of nails along the walls lol



And they certainly don't build 'em like they used to! 6 nails for a 5" piece of trim!!


Wasn't always pretty once the carpet came up


Here's how the new ply is laying down so far. I don't think I snapped a pic of the bedroom floor for some reason