0

The structural engineer says I need to shore up the ceiling here on the first floor of a two-story home, In order to repair the sole plate on the exterior wall to the right. However the joists run parallel to that wall up to a point then there are some cross joists near our entryway door. How do I sure up the ceiling in the area where the joists are completely parallel? Do I reverse the direction of my shoring wall support so that it runs perpendicular to the wall, and then switch the support wall back to parallel once the joists are running perpendicular again, if that makes sense?

enter image description here

1 Answer 1

2

Your Situation I assume:

I assume you mean to replace the plate which is in contact with the concrete foundation or slab below your main story walls? This is typically called the "sill' plate but I have heard some refer to it as "sole". I assume there is an issue where it rotted due to bad landscaping, water/insect issues, bad wood selection (not pressure treated?) and/or no vapor gasket between the wood and the sill plate? It sounds to me like the plan is to take the load off the outside wall (from the upstairs and / or trusses), so that the sill plate can be removed.

Typical Plan for Me anyway:

First, this is very ballsy project to DIY. I have removed weight from bearing walls DIY for various reasons, my first time I had an engineer and GC helping me. Example, to open up a floor plan / put in a beam, and yes to replace a sill plate. My approach - which sounds like from the request, is theirs's as well, is to make a temporary beam for inside your house as close to the outside wall as you can get. I normally just use some 2x12s maybe doubled or tripled with overlapping seams. I have guessed in the past as to the loads (cause i'm not an engineer) and then just did double that to be safe. I then make half a dozen or so posts out of doubled up 2x4s and attach them to the beam, again if you want to be safe, every 16" - I normally don't do that / depends on my estimates of upper story or roof loads. Drill small notches in the butts of posts, place bottle-nose jacks under each post, stand the beam and posts up under the wall and start jacking them all evenly till weight is removed from outside wall. I then nail or lag the beam (temporarily) in place and go about the work. In order to do this, you also have to be 100% certain that the joists under your main floor can handle this load and main story joist configurations of course matter greatly! I have been able to get away with hardwood planks that span your main story joists and place the bottle nose jacks on the planks. But, depending on joists, you might need a main story bottom beam as well.

Ask the structural engineer!

Assuming their plan is similar, you would require supportive structure in your ceiling that supports pushing the ceiling up in that spot, taking the load off the outside wall, without breaking floor/ceiling truss webbing. In your case, since the joists run parallel to the outside wall, and from your sketch it appears you have webbing. I would assume they want you to take out the drywall, and start "shoring up", firmly securing webbing or sister joists to the outside wall of the second story. This would be so that a beam underneath could have something to push against / support and push up the second story of the house. I assume by "shore up" that is what they mean.

If you've hired a structural engineer to help with this, ask him/her specifics about how they want it shored up before the upper story gets re-supported.

5
  • Can I put a temporary wall underneath webbing?
    – Chris
    Commented Jan 15, 2022 at 22:17
  • 1
    @Chris I've been fortunate in the past that my joists all ran perpendicular when doing an outside wall. If I was to try this without my structural person being more specific, I would reinforce the webbing with upside down hangers and/or gussets. No, webbing won't hold IMO without reinforcement. You're tearing into your drywall and crown molding no matter what IMO. And those windows are in danger as well. Just to reiterate, this is extremely ballsy without someone who's done this before. I had help in the beginning and would still seek out pro advice even now before doing this.
    – maplemale
    Commented Jan 15, 2022 at 23:50
  • Copy. Will seek professional construction support.
    – Chris
    Commented Jan 16, 2022 at 0:25
  • 1
    @Chris you've been here long enough to know that a helpful answer deserves an up vote and check mark.
    – FreeMan
    Commented Feb 15, 2022 at 15:27
  • 1
    Thanks take care of that. While these comments were helpful the contractor recommended going in a different direction for the final repair everything turned out great
    – Chris
    Commented Feb 16, 2022 at 16:55

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.