1 inch underlayment? Too heavy, need help!

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rafalc

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New member here hoping for some advice. I am renovating my house and the floors throughout the 2 stories are sagging (its an old house so its normal, nothing structurally wrong). In the middle of the house is the kitchen, going from the back of the kitchen to the front of the kitchen, the floor slopes an inch and three quarters! Most of the dip happens within a 5 foot distance right by the back wall.

I need to do something with the floor, either vinyl tile, laminate or vinyl sheets BUT I would like to fix the slope a bit before I put a new floor on it. Here are some ideas:

- Half inch cork underlayment - only will give a half inch but its light weight. Run it until it is almost even with the higher end of the floor and then smooth out the connecting area with self leveling compound

- 1 inch plywood - will give a whole 1 inch, making the floor offset by only 1/2 to 3/4 inch BUT its going to be HEAVY. The area that needs covering is about 12' by 12'. That's a lot of weight, no? Again, use self leveling compound to smooth out the area where the new plywood evens out with the higher original end of the floor.

Both of these will give me a nice hard base for vinyl or laminate.

Are there any other solutions...light weight solutions? Any better ideas? Suggestions? Jacking up the floors or shimming, sistering joints is out the question.

Thanks!

BTW...floor that is there now is vinyl tiles. I plan on leaving them on and doing something over the existing floor.
 
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If it were mine I'd seriously look at getting estimates for jacking up the house. I think SLC is going to be heavier than plywood.
 
1 3/4" sag is a structural concern and not normal. The correct way is to sister the joists and confirm your foundation is sound. Since you advise this is out of the question, I would recommend pulling your sub floor, shimming until level, and reattaching (glue and screwing) when the floor is level. The problem with this is the fact that if you are into the floor, you might as well sister the joists. Self leveling compound is very heavy so I would avoid using anywhere except the first floor.
 
If it were mine I'd seriously look at getting estimates for jacking up the house. I think SLC is going to be heavier than plywood.

The same exact sag goes throughout the house (2 floors and the attic). I think what might have happened is that the support columns in the basement gave a little over the years and the main beams sagged in the middle as a result. I now have 4 extra heavy duty support columns I just added. I also tried jacking up the house myself over the last 5 months, was only able to get it up around 3 millimeters which is nothing. The house is around 80 yrs old so jacking the floors up over an inch through the 2 floors would be scary as hell.

Like I said before I had multiple inspectors/engineers tell me that the structure is sound.

The idea of ripping up the floor, sistering the joints and shimming up a new floor was suggested BUT ... this is a rental property, does not need to be perfect. Benefits vs cost and time .... just doen't make sense. I don't even HAVE TO straighten it BUT I am doing other renos with cabinets, countertops, appliances so I feel like the job will not be 100% done and leaving the floor sag will take away from the other improvements.

So in my current situation...if I can't find a good enough solution of straightening it out a little over the existing floor....then it is going to be left as is.

Thanks for your opinions
 
1 3/4" sag is a structural concern and not normal. The correct way is to sister the joists and confirm your foundation is sound. Since you advise this is out of the question, I would recommend pulling your sub floor, shimming until level, and reattaching (glue and screwing) when the floor is level. The problem with this is the fact that if you are into the floor, you might as well sister the joists. Self leveling compound is very heavy so I would avoid using anywhere except the first floor.

Thanks for the advice....see reply above.
 
Yeah, if it is a rental, just cover with the flooring of your choice. My daughter lives in a rental with similar problems and it has become quite a conversation piece. It is also fun to watch things roll from one side of the floor to the other!
 
Yeah, if it is a rental, just cover with the flooring of your choice. My daughter lives in a rental with similar problems and it has become quite a conversation piece. It is also fun to watch things roll from one side of the floor to the other!

Hey.... do you mean just cover with lets say...vinyl without trying to even it out or would you recommend leveling it out with plywood, then vinyl/laminate on top? I guess I'm just concerned about the weight all the plywood would add. Am I underestimating the weight a house can actually support?

Thanks
 
If I were in your shoes, I would do one of two things. I would either fix it correctly, or not at all. One is expensive and time consuming. The other will keep the problem for a later day but look nice in the mean time.

Unless you use T&G 1" plywood, glued and screwed, you will have a very noticeable flex on the floor, which in itself would be annoying. Ad the heavy SLC and with the weight of the floor, which already has a structural sag of 1.75", and you are asking for problems.
 
If I were in your shoes, I would do one of two things. I would either fix it correctly, or not at all. One is expensive and time consuming. The other will keep the problem for a later day but look nice in the mean time.

Unless you use T&G 1" plywood, glued and screwed, you will have a very noticeable flex on the floor, which in itself would be annoying. Ad the heavy SLC and with the weight of the floor, which already has a structural sag of 1.75", and you are asking for problems.

Thanks for the suggestions. I have been leaning towards just putting sheet vinyl over it and leaving the sag....but if anyone else wants to throw out some ideas, please do!
 
New member here hoping for some advice. I am renovating my house and the floors throughout the 2 stories are sagging (its an old house so its normal, nothing structurally wrong). In the middle of the house is the kitchen, going from the back of the kitchen to the front of the kitchen, the floor slopes an inch and three quarters! Most of the dip happens within a 5 foot distance right by the back wall.

Are you simply saying the slope is from the middle of the kitchen to an outside wall? I'm just curious if there is a dip in the floor, or a slope downwards toward an outside wall (as in, foundation is sinking)
 
Are you simply saying the slope is from the middle of the kitchen to an outside wall? I'm just curious if there is a dip in the floor, or a slope downwards toward an outside wall (as in, foundation is sinking)

The outside walls are fine....at most 1/4" off towards the middle of the outside wall. The big slope is towards the middle (center) of the house.
 
Thanks for the suggestions. I have been leaning towards just putting sheet vinyl over it and leaving the sag....but if anyone else wants to throw out some ideas, please do!

Just wonderin why your throwing money at a rental unless you own it? Seems like a waste of resources.
 
You could always put a cheap piece of commercial carpet in there. It would hide the slope more.

But then what goes over the carpet? Would still need plywood to give it a sturdy subfloor ready for vinyl right? Therefore, still a lot of weight even if its a 1/2" plywood. Or were you thinking of something else?
 
But then what goes over the carpet? Would still need plywood to give it a sturdy subfloor ready for vinyl right? Therefore, still a lot of weight even if its a 1/2" plywood. Or were you thinking of something else?

How large of an area needs leveling out?
 

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