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I am working on two old houses, one my own, the other is a job remodeling a 200 year old log house. As with most old houses, the floors tend to not be level, and in the case of the log house I’m working on, the floor is out of level about 3 inches across 11 feet. My task is to level the floor, but how? Whatever method I use, it must be every bit as strong as a good solid floor. I thought I might have to cut wedges of 2x and put 3/4 subfloor over them to level it. But if I do that, then how do I make sure the floor is level both ways and stays level? I need to do this in my own house also and have been putting it off for a year because I don’t know how. In both the log house and my house, the rooms are large, and the entire floor of the room must be leveled out. Thanks in advance for help.
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Rich,
A floor that isn't level is held up by joists that arent level because of one or more of the following reasons:
1) the foundation has settled
2) the sills have rotted
3) the posts and other midspan supports have settled or rotted or been crushed over time
4) the joists or beams are undersized for the load
5) upper floors can suffer from all of the above causes plus missing or compromised support from badly remodeled bearing walls.
The reason(s) for your crooked floors needs to be determined and the underlying condition stabilized. Then you need to decide whether it is feasible or desirable to lift the floors back to their original positions, or whether you should leave the framing where it is and merely shim the floors as you were thinking of doing.
If you just shim up the floors that are sitting on top of a rotting sill or sinking post, they will only give you more trouble in the future. It is usually more than just the floors that are moving. You need to think about the house as a whole unit, and visualize its support system from the bottom up.
Steve
*Rich,Steve's right, there are any number of causes you could be facing with different solutions for each. I did notice you jumped right to shimming techniques in your post, so let me share what I would do if it were the foundation out of level and the sills (etc.) in reasonable shape.I'd use a sight level (we have a self-leveling one whose accuracy I trust) to mark a level line around the whole building and at intermediate supports (center posts or foundation walls within the perimeter). Measuring down would let me know where the high point was and how far to go up to meet it at the lower points. A water level or laser level would work for this purpose.Then I would adapt a technique I learned in a Bob Syvanen book for leveling new sills. Basically one shims the sill level (using any technique--more on this later) and fills beneath with mortar. The mortar is strong enough to hold up a house where shims are not--not unless they fill the whole space below the sill anyway, and then they'll still shrink some and crush under point loads. As for tying sills to foundation, in a 200-year old log house I wonder how common or necessary that is anyway, but I'll let someone else (probably from an earthquake zone) take a shot at retrofitting that.To lift the house, opposing shims of 2x material could do it. I think I would be tempted to use a house jack and a header that could lift 4 or 6 feet worth of sill at a time. Even a big bottle jack could do this. You'd work your way around the house lifting about a half inch at a time, leaving most of the house on the foundation (or shims) at any given moment. You may damage finishes this way though.I have seen some house movers at work--they used lots of big & small steel beams and house jacks, 4x4 cribbing as temporary posts, and about 20 people. It looked easy and only cost $10,000. They made no guarantee about finishes but claimed never to damage anything but old, unsound plaster.Hope this helps. BTW, if there are no drastic changes over a short distance, a house that's an inch out of level (over 24 feet or so) would feel level--in fact, many of the houses I've remodeled are that far off or more and it's undetectable until I go around checking in preparation to add on or install a kitchen. Do you suppose that limited shimming of the worst areas would eliminate the problem?Good luck,Doug
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I am working on two old houses, one my own, the other is a job remodeling a 200 year old log house. As with most old houses, the floors tend to not be level, and in the case of the log house I'm working on, the floor is out of level about 3 inches across 11 feet. My task is to level the floor, but how? Whatever method I use, it must be every bit as strong as a good solid floor. I thought I might have to cut wedges of 2x and put 3/4 subfloor over them to level it. But if I do that, then how do I make sure the floor is level both ways and stays level? I need to do this in my own house also and have been putting it off for a year because I don't know how. In both the log house and my house, the rooms are large, and the entire floor of the room must be leveled out. Thanks in advance for help.