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Forced Floor Truss

I have a hump in my floor that was caused by whoever framed the stair well in my basement. The issue is, when the framing was done to form the stair way, the plan called for a door at the bottom of the stairs to our basement. So, the framer framed up a door opening, angled it in under the floor truss, and forced it into place. The problem with this door frame is, it was built at 3/4" too tall, and the framer actually lifted up the floor truss 3/4" where that door frame is. So now, my floor has a hump in it at the bottom of the stairs that go to the second floor bedrooms. I have since cut the door framing down 3/4" hoping that the floor would settle, but it hasn't in 3 years. Anyone have any ideas how to get rid of this hump?


Re: Forced Floor Truss

If there is a 3/4"gap between the header of the door frame and the floor truss above, and the door frame and header are solidly connected to the surrounding framing, you may be able to use a couple lag bolts to "pull" the floor truss towards the header. Depending on the how the header/frame is oriented (parallel or perpendicular) to the truss, you could place one to three lag bolts through the header. Drill a hole through the header that is larger than the lag bolt shaft, and follow up with a corresponding pilot hole in the center of the truss. Using a couple of fender washers (you may need to counter-sink the washers and the lag head if your door frame wont clear them when installed), tighten the lags gradually over a few days. This worked well for me a few years ago during a renovation project several years ago. The key is, the header and framing must be VERY solidly bonded to the surrounding wall framing. If its not, use long deck screws to secure it. You don't want to simply lift your wall off the floor!

Re: Forced Floor Truss

Thanks JMP. I took an LVL and some clamps down there to try and pull it down and secure it to the top of the door frame and as I was releasing the clamps, I could see that it was going to pull the top of the framing up. The framing is secured to the cement floor, but I cannot guarantee that it will not pull up there either. And when I had the bottom of the truss pulled down to the framing, the top of the truss was still bowed. It probably only dropped 1/4" or so at the top of the truss. Plus, I think it may have affected one or 2 of the adjoining trusses slightly. Plus, this thing has a lot of memory and wants to spring back to it's warped position.

I would like to try and pull it down from the top of the truss, but have yet to figure out how to get a good grip on something solid to pull down from. If I had a wood floor in the basement, I believe it would be much easier to bolt something down and start pulling. I will keep digging, and appreciate any suggestions that anyone can give.

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