I have a question about soft spongy floors and how to correct them. My house was built in 1990 by a fly by night outfit. They used OSB for all the floor decking and now, 15 years later, it really is spongy. When my 45 pound daughter walks by I can feel the floor sink between the joists. God forbid when some one big walks by. Is there anything I can do to repair it? Do I need to tear up the old stuff and put down some plywood or should I place new plywood over the old OSB. Thanks for your help.
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Does your house have a crawlspace or basement?
Yes you can overlay OSB provided it is has not deteriorated.
..................Iron Helix
Full basement, two stories and a walkup unfinished basement. How would I address the diffenence in heights between the stairs and the floor or do I ignore it?
so you can inspect the subfloor from the basement
get down there with an awl and start poking... then come back and talk to us..
how thick is your subfloor ? how many layers of florring ... what size are your joists.. how far apart are they ?
what is the span of your floor joists ?Mike Smith Rhode Island : Design / Build / Repair / Restore
The house was built in 1990, it has 2x10's, 16 oc with a 12 foot span. The deck is 3/4 OSB and seems pretty good. I tried poking it with various sharp tools because I don't have an awl; a 1/4" chisel(?) and a pointed scraper. There are smoe steel X-braces but they aren't tight. I can grab them and move them pretty easily. I would also have to say there are a disproportionate amount of squeaks in the house, particularly in the kitchen and in front of the sink of the master bath.
The floors are one layer of osb, with a finish layer of vinyl in the kitchen and hardwood in the living room and dining room. The rest of the rooms are carpeted.
Edited 3/9/2005 8:34 am ET by learner
learner.. based on the sizing.. and your lack of rot or wet subfloor..
there is no reason for it to be flexing..
what size are your joists now?
are they 9 1/4" 9" 8 7/8".. measure about 5 of them in different locations
also.. are there a lot of cracks at door casings.. gaps in your wood trim ?
where are you located .. what state.. what climate ?Mike Smith Rhode Island : Design / Build / Repair / Restore
I am in Easton, PA, which is on the Delaware river about one hour north of Philadelphia. We get a pretty big range of weather types. My house is about two miles from the Delaware. Most of the joist are around 9" now, some down to 8 7/8" and some still at 9 1/8". There doesn't seem to be any big gaps at the casings around doors, but there are some pretty big gaps between the door itself and the casing, and in one case the door won't really latch unless you lift up on it.
learner... your house is drying out too much.. the joists when you installed them were 9 3/8..
the 1/2 they have shrunk is allowing your subfloor to be unsupported in a lot of areas
measure the indoor humidity of your home..it should be between 30% - 50% RH
the moisture content of your wood should be about 12%
you probably need to humidify your home
that's me without visiting your house..
but 3/4 OSB should be fine .. millions of houses are built with it.. just not any of mineMike Smith Rhode Island : Design / Build / Repair / Restore
We got a humidstat for christmas a couple of years ago and I just checked it out, the humidity is around 23%. We have two humidifiers, one in the furnace and a stand alone, together the highest they have brought the house up to is 33% or so. I don't think I have ever seen 40% in our house, particularly in the winter. If humidity is such an issue wouldn't the problem get less in the summer? I have not noticed a decline in squeaks or soft flooring in that season.If I add blocking would you guys recommend wood X type or use the steel type, of which there is some. However, quite a few are pretty loose. On another note, why don't you use osb?
Edited 3/9/2005 11:23 am ET by learner
Get down in the basement and watch both the sub-floor and the joist and some one walk back and forrth across it.Do it both by the supporting beam and by the outside wall.I seem to remember some case where the joist where not properly supported at the ends.But I don't remember what the cause was.
I have kind of done that. I first did it with my sister in law( who is pretty big) and then with my kids(only about 100 #) and you can see the flooring sag under their weight. If you watch closely, you can see the sag when my dog walks over it. I'll have to wait until my older kids or my wife come home to check the floor at the beam or the foundation. If you don't mind me asking what will this information tell you?Thanks for your help and time.Just read the post about cupping and can add that at least one joist in the kitchen is crowned up, I laid a 4' level perpindicular to the joist and there is at least 3/4" difference on that floor.
Edited 3/9/2005 1:52 pm ET by learner
"If you don't mind me asking what will this information tell you?"Is the sub-floor moving with respect to the joist?Is the joist bowing in the middle or twisting?Is the end of the joist moving at the beam and/or at the rim joist.Each of those are different types of probems.
Well I had my 114 # daughter walk and bounce up and down at various places in the kitchen and family room. The sub floor was moving and the joists were moving up and down. Sometimes independently and sometimes together. The osb also moved between the joists. One of the joists seemed to twist a little bit, the rest just moved up and down. The X bracing is pretty much nonexistant. The stuff that is in place is loose. Some of it was removed to run HVAC ducts. How tight should those braces be, and does it matter if they are metal or wood?
For the braces to be effective they need to very tight.But I don't think that is your problem.Now I am not a pro, but from what I understand that you are saying the end of the joist are floating.
From what I could see the end of the joist don't really seem to move except for one on the center beam, it seemed to twist a little bit. How do you get the straps tight, if your using metal ones? If you miss a joist because of duct does it matter or should you put some blocking across the bottom? Also what kind of spacing should you use? My joists are 12' long, should I put them every 3' or 4' or 6'?
i liked you better when you were learner.. you seem a little more cocky now that you're steve
but hey , steve .. pulling up the subfloor is a bit*h.. it goes under every wall.. it's under your cabinets.. it's under your stairs
this is not an easy thing to do.. and it's very difficult to do it well
i'd do a lot more investigation before i started down that roadMike Smith Rhode Island : Design / Build / Repair / Restore
Yea, I really agonized over telling people my real name, what with ID theft and all. I figured you guys all did it so why was I being shy. Almost got zinged a couple of times but was lucky. As far as pulling up all the flooring I was thinking up to but not under walls and stairs. The kitchen is another issue, I want to remodel that anyway, open it up and all. I saw the toe kick saw on another post and thought that would be a real easy way to rip it up. Lots of people say just go over the old stuff but I still have the question about the height of the first and last stair heights.
I've read your thread thru here, and while I don't have a definite opinion ( other than that those metal cross braces are a good laugh) I lean to beluieving that your subfloor got wetted too much during the construction process. Why ?
Because OSB is the least forgiving of any subfloor material.
Because you live where it rains a-plenty.
Because there are plenty of poor builders all over who would use OSB and keep right on a-building when it gets damaged.one fix MIGHT be to replace the vinyl and carpet with solid hardwood flooring run across the joists and glued down with the flooring nails hitting joists as much as possible.To deal with the sloppy metal strapps, I would probably put in strapping ( 1/3s) at 16" oc under the joists. Anotjher thing I noticed was the proximity of the copper to some of the other metal. Make sure they are not in direct contact, or the coppr may corrode more quickly there.
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this sounds like classic shrinkage...
and maybe some bad framing thrown in...
don't you know of any experienced builders in your area ?..
the metal bridging is ok.... but it's not doing anything for you .. and it's not the reason your floor is floating around..
do you have a rim joist ? do your joists lap over the center beam or butt to each other ?Mike Smith Rhode Island : Design / Build / Repair / Restore
learner, do you have a digital camera or know someone who could take some pictures for us?
I think we would like to see pictures of where the joists meet the rims, and if possible, how they are connected (hangers or such).
I would also like to see where the joists and the subfloor meet, and see if there is space for a shim - and what the thickness of the shim is, when it stops going into the space.
I'm not a framer, but I'll venture to guess almost every mistake possible was made there:
The joists were not crowned;
The builder did not glue and screw, but probably only nailed the subfloor to the joists;
etc.
Let's have a few pictures, please.
It'll be easier for us to diagnose the problem and help you fix it.Quality repairs for your home.
AaronR ConstructionVancouver, Canada
Here are some pictures, I think, I hope. They were glued and screwed, I tried to take pictures of that. I know one guy but when I went through a house he was working on I was not to impressed. When I talk to him about some of the stuff I've read about I get answers that are sort of off putting. I don't know who built this house but I don't think they took to much time doing it right.I can fit sandpaper between some of the joists and the osb, I tried a joist by one of the pictures that shows the glue. Interestingly enough of all the floor decking that I can see in my basement only one piece has printing on it but pertinent information is missing, except for one which reads, "This side down". None of the other osb has any printing on it. I can't believe that they installed all but one piece upside down. Could they?
Edited 3/9/2005 10:44 pm ET by learner
learner.. you have a rim joist.. and your subfloor was glued and nailed..
the metal bridging was useless from the getgo ( looks like it was never tight )
your joists lap over the beam..
what's the beam made of .. how many pcs of 2x10 ?
frankly, i see nothing wrong that meets the eye.. i still think you've got excessive shrinkage..
with the materials and the spans you should not be getting the action in the floor that you are getting Mike Smith Rhode Island : Design / Build / Repair / Restore
The beam is 3 2x12'sI really appreciate all of you guys taking the time out to check this out and posting your advice. I am definitely going to do some work on the blocking/strapping.
Edited 3/9/2005 10:48 pm ET by learner
Just out of coriosity... and a possible cause...
You mentioned you had hardwood floors. Is it real wood... or a laminate (like Pergo)? Is the floor floating?
The reason I ask... almost all laminate wood floors have a pad under them... and will create a weird soft feel.
From the pics... there is nothing that really stands out.. other than the uselessness of the x-bracing.
I see one area where the OSB has pulled away from the joist, but this is not causing what you are describing (I think). (pic 6)
I believe that your floor was stapled.. I can see a staple or two that missed the joist (unless you have a rea hardwood floor, and it was stapled.).
The joist and the osb are moving in unison? With a slight twist? X-bracing may cure the twist... but not the bounce. I wouldn't put the x-bracing on the top of the list... but it won't hurt.
As far as the OSB upside down... not a big deal... not the way I would do it... but not a real big deal. As long as the house was under roof quickly after the sub-floor was put down. I always check the orietation... but I have seen LOTS that have "this side up" facing down.
OOOHHHH... have you indicated whether the OSB moves independently of another piece of osb directly beside it? You would determine this by watching the joint of the OSB as someone jumps or walks upstairs. It COULD be that the sub-floor is not T&G?
When you say that you can fit a piece of sandpaper between the joists and the OSB... how many places are we talking about? Are those places where you are getting the bounce?
And could you further describe the crown condition (the cupping question from earlier)? Especially how the joists compare to those beside the ones that cup down. Is it "up, down, up"... or a "down, down, down"?
I agree with mike that you have uneven shrinkage. that can be fixed with some shims and PL. But you describe a "bounce" that is much more than what this would cause. Or am I misunderstanding the amount of bounce (there will be a small amount of bounce simply because wood, by its nature, "gives" a little)?
So many questions! This is great! Thanks so much!<<You mentioned you had hardwood floors. Is it real wood... or a laminate (like Pergo)? Is the floor floating?>>The hardwood floor is real oak, 3/4 inch T/G directly on the osb subfloor. I think the staples you see are from that installation. There are actually more squeaks coming from the carpeted floor in the family room and the vinyl in the kitchen. The softspots and squeaks also MOSTLY come from localized areas that are what turns out to be more in the middle of the span of the joist, except in front of the kitchen sink and in front of the sink in the master bath. <<It COULD be that the sub-floor is not T&G?>> Nope, I've seen the T&G on the edges.<<When you say that you can fit a piece of sandpaper between the joists and the OSB... how many places are we talking about? Are those places where you are getting the bounce?>> A couple but I'm not sure of all the places. I definitely get bounce there. I can also see the osb moving between joists, actually moving up and down, when my daughter bounces in the different spots.<<And could you further describe the crown condition >> It looks like one joist is the big culprit. It is easily 3/8" (in one area) "up" while the rest are down. I can't see all of it because the outlet and return lines for the furnace and AC interfere. One other joist right next to this one is "up" by about 1/4". <<with some shims and PL>> Is that PL premium? (My favorite bottle rocket glue?)Could someone post a picture of what you mean by blocking? I have an idea but I am not sure if it's what you mean.
BTW... I assume that you have made the conscious decision not have insulation on the basement wall down to the frost line?
Just something I noticed... along with the wiring... but that is a different story and a different thread.
OHHH... just had another brain cramp! How big are those holes for the wiring? I can't quite make it out from the pics. Again... not a be-all/end all... but if the hole is large, and through every joist.... it COULD be one of the sources of the problem.
Funny you should mention that because that is the subject of my other post (superinsulation retrofit). I do want to insulate in the basement. If you don't mind I'll carry that on over there. ON the subject of the hole diameters they are 1.5", 3" from the bottom, and three in a row, for 11 of the exposed joists, and I am sure they continue in the joists over the garage.One other thing I noticed was that one of the bad areas is on a joist that is terminated short of the beam, for a dumbwaiter well. To bad I can't get a hanger in there, there are HVAC ducts in the way.
Edited 3/10/2005 2:34 pm ET by Steve short for Stephen
When you mention insulation do you mean the outside of the foundation or the inside? If you do the outside how do you protect it and make it look good? Do you use some kind of Stucco?
Inside... I call it a "basement blanket".
Insulates the basement down to the frost line. Save ya a few pennies on energy costs.
Supplementing what Mike had to say about the humidity levels...
I am also inclined to believe that some of the floor joists may have been installed crown-down. If the house has dried... and the joists are pulling in opposite directions.. then you could have a bouncy floor. If the OSB is spreading the gaps created by one joist bowing down and two bowing up... add in the uneven shrinkage... and you could have a real bouncy floor.
Check the "straightness" of the joists by climbing to the joist and eyeballing the bow of the joist. If one is cupping up (or straight)... and one is cupping down... then the next is cupping up... then the solution is a little more mechanically involved than just adjusting the humidity (although that will not hurt).
Mike, I make it a practice to glue and screw, not nail. I'm sure you do too.
In my area it's possible to get framilng timber really wet, but I don't normally see OSB as a subfloor. The construction adhesive I saw in the last picture tells me that really, everything should have been moving in unison.
Except if it was put down wet glued and nailed only, and the nails were smooth. As the joists dried, they shrunk and with constant movement the glue bond is letting go and the nails are not biting into the wood enough to make the structure solid.
What do you think?Quality repairs for your home.
AaronR ConstructionVancouver, Canada
> There are smoe steel X-braces but they aren't tight.
That's important. Loose braces are doing nothing for you. A row of blocking, or even better two rows, cut and installed as tight as you can get it, will keep the bottoms of the joists from twisting, and transfer some of the load to adjacent joists. Glue shims into any gaps you find between the subfloor and joists. Those two fixes should solidify things considerably.
-- J.S.
If the floor is moving between the joists it might not be t&g OSB. Check it out from underneath. you should not be able to slide a thin piece of material up on the long joints to the underside of the floor finish. If it is not t&g then you might have to glue and screw/nail blocking.
Is it doing it everywhere?...if it's localized, they may have missed the joist on a joint and fudged it....
What if..............????
The builder bought and installed osb "seconds"/mill rejects?
The osb run was defective and lacked the appropriate amount of resin/glue?
The osb was exposed for a long period of "rain" and has delaminated?
Can you see a mill stamp on the OSB?...it can be checked out!
Just some thoughts...................Iron Helix
PS.....did a house once where the OSB t&g failed. It was discovered by the vinyl installers...called in the GP rep and sure enough that mill and run number came up as potentially faulty. GP paid for a complete overlay plus labor!
Steve,
A lady I work with is having similar symptoms. This isn't to say that this is what is causing your problem. Her house was built in the early 90s. Her problem is that her OSB sub floor is delaminating in lots of spots and so her floor is very spongy in places. Her contractor is out of business but says it is the fault of the company that made the sub floor. The subfloor mfg says it is the contractors fault for allowing the subfloor to get too wet during installation. So until the lawyers can sort it all out, she is joking about putting orange construction cones in the soft spots to warn people where not to walk.
Regards,
Dennis
Actually, this is one of the major ideas that I have been bouncing around in my head all along and so am wondering if the ultimate fix is to rip the osb off and put in new wood or do I just lay new wood over the old? One is definitly worse than the other. And if you just overlay with another layer of 3/4" sheeting what do you do at the stairs? Not worry about the extra 3/4"?
Listen carefully to Mike. Explore every available option prior to attempting to replace the sub-floor.
If the OSB is spongy in some places but not others, and deflecting down between the joists in those places, here are some things to consider:
Orange cones or not, work with a helper upstairs while you watch down below. Map out and mark where the good and bad regions are.
When you know where and how big the bad places are, you can make a decision on how to approach the problem.
If it's most of the floor, ripping it out and re-building might be the way to go.
If it's just a few places, not too much total area, you might be able to support it from below. Rip 3/4" plywood to fit between the joists (about 14 1/2" wide) and hold it up with 1x3 cleats glued and nailed to the sides of the joists. Use two layers of ply, and stagger the ends. If the total area is small enough, that'll be easier than messing with the finished space upstairs.
If it's just a few bad places, chances are they're where the water puddled before the place was weathered in.
-- J.S.