Home>Discussions>INTERIORS>Molding & Carpentry>wall dropping due to inadequate floor joist
8 posts / 0 new
Last post
Gma Bee
wall dropping due to inadequate floor joist

My kitchen wall has dropped an inch causing a dip starting 4 feet from the wall. The wall sit parallel to the joist. I am redoing the original kitchen and need that taken care of. I have had no kitchen now for 3 months while trying to figure out the floor issues. The joist under that wall is only a single joist. Plus when the house was built that joist was patched. The joists there are 2x10 on 12" center and span 18' which is the garage area. About 7 feet of the wall sits over the garage. The rest of the wall sits on the center main beam and then over a double joist in the basement area. The rest of the house has 16" centers. The area with the patched joist and dropped wall above is right in front of the door from the garage to the basement and also has the main AC/heat duct work in the area. I've had many companies here for other issues with floor joists in the rest of the house and have different opinions as to how to fix this. I can do a lot of repairs myself but this I know is beyond my abilities. Dealing with all the 'opinions' I ask - why do I have to be the expert. Any help or advice would greatly be appreciated. Thanks!

I have pictures but not being accepted....

Re: wall dropping due to inadequate floor joist

One of the easiest and strongest fixes for a sagging joist is to sister it with ΒΌ" steel plate.


Gma Bee
Re: wall dropping due to inadequate floor joist

Would that be a steel plate sandwiched between original joist and new joist? Problem would be accessing it. Have main vent trunk line there and further down lots of electric wires running through holes in joist. Interesting no professional who has been here suggested that. Most just said if was their home they'd leave it alone... In general is this something I should really get a structural engineer -- heard they too may have differences of opinions. I'm probably over cautious now cause had someone beef up joists in other areas - and he added partial length and depth wood to joists (glued and screwed). And added a floor jack post from Home Depot in couple of places - used doubled 2x8's flat on top that spanned 3 joists - to lift and stabilize where was issues on main floor too. Every company who has been here now has looked at that and just shook their head - saying it's a 'band-aid' at best. I had trouble getting in contact with that guy who did work this summer - had not addressed other joists that had cracks like he was supposed to. He did call now and when I told him what everyone else said (structural specialty companies, general contractors, construction companies) he couldn't believe it and still stands behind what and how he did work.
I've seen been trying to learn as much as I can -- but I know I'm not the expert. Saw this forum and thought I'd try here for advice and to learn.

Gma Bee
Re: wall dropping due to inadequate floor joist

But would think have to do something about the inch drop in kitchen floor (from wall to 4 feet out) and sure don't want any further drop! I understand the ridge in the middle of the floor that is over the center main house beam can be plained/sanded down and feathered from on top. But would be concerned about the drop. Thoughts...??

Re: wall dropping due to inadequate floor joist

With a span of 18' you may be border line or even over the allowable span, depending on the live load.

I recommend talking to an engineer.

The posts and jacks are just temporary, you know. They will prevent further deterioration, for the right now.

Re: wall dropping due to inadequate floor joist

The 'Flitch plate" JL mentioned is probably the easiest solution so long as there is nothing in the way. Sistering with enough added one-piece lumber may do as well, or adding a ripped-to-fit LVL beam. You will want to jack everything back into it's proper place before adding anything to ensure it stays in position. If it makes the job easier and looks like it will work, you could split the new 'beam' material at the supporting wall, you may have to reinforce the studding in it though. It's hard to recommend one method over another from here- I'd base that decision on how strong the sag tendency is and what kind of room I have to work within. I've dealt with lesser loads by blocking tightly to the joists on either side being sure they were well-secured from top to bottom everywhere, but I think you need more than that here.

Kind of makes you want to punch the framer who didn't properly double the joist under the wall to start with, doesn't it? :eek:


Gma Bee
Re: wall dropping due to inadequate floor joist

Thanks for the advice. The part of the wall under the single joist is over garage and not at all clear to work on -- naturally.

Someone last week asked if the wall had dropped why hadn't ever been damage or crack or -?- on the drywall or at the ceiling or .... Can't answer that. It had been a doorway (with door) there and we closed that off 18 years ago and made a double door opening (no doors) further down the wall. That opening area has no floor problem but that's where there has been a 2nd joist full size joists sistered to the original single one - also 18 years ago. It's to the other side of the center beam.

I have no idea if there was a problem with floor and wall dropping there when we closed off the doorway years ago. My late husband was in charge of all that... I'm getting a real education now and want/need to know.

Thank you everyone!

Gma Bee
Re: wall dropping due to inadequate floor joist

Yes - - about being upset with builders who only used single joists - and a compromised at that! Have found lots of 'short cuts' done with other things. Like NO brick ties. Discovered that when L beam over garage door was bowing and pulling bricks off side of house. Now there is an I-beam - and lots of brick ties! At least brick ties on that wall area. - - - Where were and who were inspectors - - who knows! Codes shouldn't have changed that much over 40 years - I would think!

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.