Should I jack up the joists to be flush with the beam or just shim the beam to avoid drywall flexing during installation?
Asked by Ludvig Reyes 
3 months ago
Last Updated: June 18, 2024
Hey, remember when I mentioned those cracks in my ceiling a while back? Well, I finally got around to checking them out and it turns out one side of the crack was pretty loose. I tried screwing it back in place, but the screws kept popping through the drywall. After a few failed attempts, I decided to just open it up. Now I see that there’s a beam there that’s higher than the joists. Not sure if the joists have sunk over time (my house is from the 70s) or if it was always like this. Do you think I should try to level the joists with the beam or just shim the beam so the drywall fits better? The gap looks wider than the difference between the joists and the beam. I included a pic with a lighter for size comparison. Any thoughts?
If you attempt to lift things up on the lower level, you might end up with cracked drywall on the upper level. I suggest gluing the drywall/screwing it, adding extra glue to the beam to allow the drywall to move freely.
Try shimming it. If the joists are sagging, you would see cracks in the walls, floors, and doorways. Shim it and you’re good.
There are some other cracks. They’re just smaller.
Apply shims/furring strips to the beam. There may have been some settling, but if you don’t notice any cracked drywall or sagging floors in other areas, this is the approach I would take.
As long as the ceiling above is stable with no bending or fractures elsewhere, I would simply use shims as others have recommended. I am interested in the type of hardware chosen for hanging the floor joists.
Just leave the bottom of the beam as is, it might have been intentionally built that way by the rough framers. No need to mess with it.
Especially during the housing boom of the 70s. I can definitely say that about southern CA. That’s when a significant shift occurred in the industry.
Framing contractors began using framers from south of the border who were still learning. Things have improved a lot since then, but the houses framed in the 70s are pretty bad. I work as a door hanger and finish carpenter, and I’ve encountered some really bad stuff when installing crown moulding.
I’d shim it, I wouldn’t mess with anything on a structure that’s 50 years old.
Take a look at the floor above. There’s a 6′ level and some marbles.
What’s on the floor above?
Dropped joists at a beam are a pretty common problem when they’re just nailed. Using joist hangers can prevent this issue. Even if you don’t raise them, I would still recommend installing them to prevent further dropping.
Looks like somebody did a rushed job with 90⁰ simpsons at one point, hangers needed.
Yep, just shim it
You can easily bypass that with drywall, but avoid nailing into it – focus on hitting the joists instead
While the area is open, it would be a good idea to make sure each joist is securely fastened.
It is worrisome that the joists on both sides of the beam have dropped down. I am curious if the tops of the joists align with the top of the beam.
I would suggest checking the floor above to see if there are any signs of sagging. If not, consider installing proper joist hangers to prevent any further movement and shim under the beam. If the floor above does show signs of sagging, you could try jacking it up slightly and then installing the joist hangers. Ultimately, the decision is yours to make since it’s your house. Do you know what is located above this area?
Remember to check where the joists are located before reattaching the sheet rock and only secure screws at the joists. The beam is narrow, so you can go a certain distance without needing a screw. The only reason screws were used was because they had to be secured into the beam itself. Otherwise, everything seems to be in order.
Shims are definitely the best option. Using jacks could cause additional cracks in different spots.
Drywallers should have been able to handle that job. It may have been better to use a solid member beam.
If there’s a joist that’s not level with the others, jack it up and attach it with lag screws.
‘ lag screws won’t be able to handle that weight. You’ll need joist hangers instead.
Hey , Lag Screws are sturdy fasteners specifically for connecting heavy lumber or materials under intense loads.
You’re absolutely right. The beam is responsible for carrying the load, not the lag screw. They’re not meant to handle shear loads.
I’d definitely use shims and call it a day at this point. If you start jacking without opening up more to fully understand what’s happening, you’ll likely encounter even more issues. This is especially true if the area under where you’re jacking isn’t able to support a continuous load to the ground. The same applies to joists and beams – if you lift one end, the other end will lower, causing issues like cracking drywall in various areas.
Oh, before you seal it up, it might be a good idea to reinforce the beam with some nails/screws.
It seems like the hangers you have are not the right ones. You should use a “beam hanger” or a “flange hanger” that wraps over the top of the beam. The ones you have appear to be joist ties, which are not meant for supporting joists. The nails in them don’t offer much shear strength, which is likely why your joists are sagging. I would suggest getting a licensed contractor to inspect it.
I wouldn’t bother with jacking it up, I’d just slip a piece of plywood in there and secure it with screws.