2nd Floor Sag

[djphilly]

My house, which i recently purchased, is approx. 25 years old and there is maybe a 1" sag toward the center of the 2nd floor. It gradually slopes in from all sides of the house. All support for the 2nd floor comes from the perimiter of the house (no internal posts from 1st floor), but the house is only about 15' wide (it is a townhouse).

Is this normal for a house of this age? Does any support need to be added to the floor? Is it possible to level the floor without repairing anything structural?

djphilly

[Jimmer]

djphilly,

Welcome to the forum. If your floor is sagging 1" in 7.5 feet then that is going to be very noticable and can be fixed. You could literally pour a level floor on top of the sag but you are adding additional load and not fixing a problem that is likely only going to worsen.

The process I would use would be to first decide if a post or two in a line down the middle of the room could fit in to your furniture arrangements and traffic patterns. Depending on how deep your townhouse is and the layout of the rooms you may want two or three supports. You would need to install a beam down the middle of the room (to spread the load across the joists) and position support posts in the spots you can live with. Where the beam hits the front and back walls you would also install supports. In the basement directly under the first floor posts you would also install posts to carry the load down. The support posts can be 'wrapped' with a decorative wood round or square column as fancy or plain as you wanted.

Another option would be to remove the drywall ceiling on the first floor and jack each joist up 'sister' an additional joist onto the sagging ones. With the ceiling removed I wouldn't be surprised if you found a number of the old joists compromised by plumbing, ventilation and/or electrical holes. It would not require any permanent posts. You would have a mess for awhile and require lots of temporary jack posts to raise the sagging joists up.

If you want further details and specifics please let me know and I continue the explaination.

Good luck, Jim

'Just a handyman trying to help'

[djphilly]

Thanks, Jim, that's a very helpful description. The first option probably wouldn't work b/c the level below the 1st floor is actually the kitchen and dining room (it is only partially submerged), and I'm not sure beams could be fit into that space. The secon option sounds like it would work better, at least from a functional perspective.

I measured the sag last night using a string held tight across the length of the floor, and the gap between the string and the floor at the low point was actually closer to 1/2". It is definitely noticeable though, and the floor actually sags at a couple different points, as though some joists have warped and others have not.

Given that the floor has only sagged 1/2" in 25 years, would you recommend just shimming between the joist and the sub floor to smooth it out, or do you think that over time the problem would just get worse and complicate a permanent repair?

djphilly

[Jimmer]

djphilly,

Alright. Is there alot of bounce in the floor, or does it feel solid. If the floor seems solid and there are no cracks in the ceiling below the to may have been that the joistd where no installed crown up and/or where very green when installed. Is the ceiling below noticably sagging in spots? If you can live with the ceiling below staying the way it is then maybe you should go back to your original question of pouring a new level floor. You would be replacing your floor coverings on the second floor but there would be no mess on the first and no support posts. A product like STAUF FLC-500 leveling compound could be used. It will fill sags up to 5/8" without any additional materials. It is self leveling and does not off gas. For your 1/2" sag this could be just the answer. Do a Google search on floor leveling compound and check out http://www.stauf.de/a/flc-500.htm , they have an office in Tennessee. Be sure to enquire about the off-gassing , weight and flexibility of any other probucts you look at.

Good luck, Jim




'Just a handyman trying to help'

[djphilly]

the floor does bounce in spots. it feels like the sub-floor is raising from joist (or hardwood is raising from sub-floor). there are no cracks in the ceiling below, and the sag is not noticeable. i will look into using a compound - i'll probably have a professional at least look at it before doing anything.

djphilly