joistsold-housesubfloor
My house is about 118 years old and I can tell from all around the house that there seems to be a sagging on my floors in one specific area. This sagging is obvious in the first and second floor. Now I just want to make sure that this is normal and if it needs to be fixed who should i call and for what price.
The sagging goes down to about a max of 2 inches and the floorboard feel loose throughout the entire second floor because of it. Any help would be greatly appreciated!
A properly sized floor joist should never deflect. Is your bed a water bed?. Joists are supposed to be sized to handle a minimum of 60 to 80 pounds per square foot, which is actually a lot, since loads are distributed across the entire span. If you are seeing ridges, cracks, or movement under load, you have a problem. I have seen joists wain, crack or even fracture at a fault in the wood grain. If this situation has gotten worse, or happened suddenly, I would seek a pro to take a look. Don't want to scare you, but this is not normal and warrants further investigation. This is not a job for an amateur.
Since you can get to the floor from underneath, you can shore up the flooring by adding new joists between the existing ones. This will not be a FUN process, but the process is simple enough, just labor intensive.
First, add cross braces between each joist at each end, of the same dimensions as your existing joists. You'll want them to be snug fitting between each joist, and well supported with joist hangers.
Now, between each brace, halfway between each existing joist, hang new joists to fit between the cross braces you added. Before you permanently hang the joists, prop them up from beneath with 2x4 temporary posts to force the tops up to be level with the tops of the existing joists (pushing the flooring above back into shape), then secure them permanently in place with joist hangers.
Add blocking between the old and new joists as well, to ensure the new joists don't warp/twist.
See the pic attached to help clarify what I mean
Best Answer
The short answer is call in a structural engineer to get a grasp of the problem and the scope of work necessary to fix it. I have a similar situation with a 170 year old home. The 1st floor foundation work was done by a licensed foundation company from the area. The 2nd floor sagging issues are being tackled by a licensed general contractor with a background in structural engineering. We contacted 5-6 companies for estimates on the repairs and got 6 different solutions. It's hard to compare quotes when the scope of work is different from quote to quote and we are not qualified to know which is the right solution. With a structural engineer on board, the engineer sets the scope of work and the companies bid on doing it exactly the way the engineer's report states. It's the only way to be sure the structural solution is the correct solution and compare quotes fairly.