[RyanUsesThis]

hello all. This is my first thread/post here and I'm hoping to get some advice on a problem that I can't seem to find much info on.

I bought my first house 2 years ago, and I'm starting to find all the little band-aids that the previous owners used to cover up flaws in the construction.

One of the main problems I've been looking to correct is a sagging floor, which I'm well on my way of doing with floor jacks, and extra carrying beams, but the problem I'm still trying to figure out is how to fix a "Bell" in the floor that occurs directly over the center carrying beam.

When measuring the distance from the basement floor to the joists to see how much I'd have to push them up to correct the sag I noticed that the joists are not as tall as the center carrying beam, and therefore the subflooring has to drop about 1/4 to 1/2 from the beam to connect with the joists. See below...

Has anyone had experience fixing a problem like this?

 

[RyanUsesThis]

anyone? Did I post this in the wrong place?

 

[Bud Cline]

FIRST PROBLEM is you canot measure from the floor to the joists in various locations and expect any real accuracy. You can not depend on the floor to be flat and I can promise you it is not.

Your best-bet is to install a rotating laser beam. Set it any elevation you choose as long as it rotates plane. Then measure down from the various joists to the beam for accurate measurements.

Does the floor bounce when you walk on top of it?

 

[RyanUsesThis]

Hey Bud, Thanks for replying. Yeah, the floor might as well be a trampoline... I get nervous when people start jumping around in my place.

As for getting the floor level I'll probably do as you say and get a laser level, or borrow one from a friend. I was just doing some preliminary measuring to see what I was up against.

All in all the floor doesn't sag all that much as far as I can tell. My measuring only showed about 1/4 difference between the center of the Joist and where the joist sits on the beam.

The Problem is the bell going over the beam that makes the sub floor rise another 1/2 or so... so from the center of my floor upstairs directly above the beam to the lowest point in the floor is nearly 3/4 of an inch.

If I were to push the floors up with jacks to remove all of the sagging I'd still be left with about 1/2 of drop from the floor over the beam to the center of the floor.

Am I making any sense? I've gone cross eyed explaining it

 

[Aggie67]

My house was built in 1975, and when I redid the kitchen and took out a hip wall, I discovered that hip wall was hiding a seam between the floor in the kitchen and the floor in the dining area. It was a 1/4" difference, at least. I took the parquet up on the low side for about 3 feet and put some leveling compound down to try and even it out. It turned out ok. It's not what I'd like it to be, but I wasn't in the mood to take the entire floor up and lay down some additional sublfoor to build it up (which would have been the right thing to do).

 

[RyanUsesThis]

That sounds about the same. I'm not looking forward to see how much the floors drop from the sides of the house, but I have a feeling it will be at least a slight incline.

I'm not sure how safe it would be but I was thinking of jacking up the floors so they're good and sturdy, then cutting out the portions of subfloor directly above the beam so that the subfloor on the joists will sit flat on the joists right up until the beam.

Then I can put the leveling compound over the beam to even out the difference between the first layer of subfloor and the top of the beam. After that I'd be able to put in a new second layer of sub floor and it should be level across the area of the beam.

This would be a huge pain in the ass job, but I'm so obsessive compulsive about floors being level that I'd do it without a seconds hesitation if I didn't think there was a chance of bringing down the whole first floor of the house.

 

[Bud Cline]

HOLD ON! First things first.

What is the size of the floor joists?
What is the spacing of the floor joists?
What is the distance the floor joists span without any support?
What is the species of the floor joists?

Then I can put the leveling compound over the beam to even out the difference between the first layer of subfloor and the top of the beam. After that I'd be able to put in a new second layer of sub floor and it should be level across the area of the beam.

A-h-h-h! Probably not!
Once any self-leveller is in place you wouldn't be able to add any additional subfloor material over it unless it was more self-leveller.:no:

What is the size of the floor joists?
What is the spacing of the floor joists?
What is the distance the floor joists span without any support?
What is the species of the floor joists?

 

[RyanUsesThis]

I'll try and answer these from memory... not at home at the moment.

What is the size of the floor joists?
2"x8" - Previous owner had no reservations about cutting huge knotches, and drilling holes through the joists far from the center.. so I'd say at best I'm getting the support of a 2"x6" most of the time.

What is the spacing of the floor joists?
Approx. 16" on center.

What is the distance the floor joists span without any support?
This is a tough one, and I'll have to get you precise measurements when I can, but I'd have to say at least 12 feet.

What is the species of the floor joists?
Pine... specifically, I couldn't tell you. the house was built in '64, and it looks like it started out as a summer cabin

 

[RyanUsesThis]

Well, I figured it out. I figured I'd post the answer so that if anyone else is search for something like this they'll have something to go on.

The board that is connected to the beam that the joists sit on must have sagged over time. It stands to reason that the joists were originally cut to the proper size, and over time the board that they were sitting on, since it was only bolted to the main beam, sagged causing the joists to drop about 1/4. So the subfloor just sagged with it causing the bell.

The solution is to jack up each individual joist at the beam so that it's even to the beam again, and tack it in place, or better yet use a joist hanger to keep it up.

Thanks to everyone that responded!!