load-bearing wall question

gbrady

Hi,
Last weekend I opened up 9.5 feet between my family room and living room, removing that much of a load-bearing wall between them. My joists are spliced and span 15 feet on either side of the room. The wall is on the first floor of a two-story house with a truss-built roof.

I consulted with a structural engineer who did calculations and said 2 2 by 12 inch lvls would be more than enough for the application. He also suggested doubling up the king studs and resting the header on 4 by 4 posts. I did all this. I also provided 2 by 10 blocking in the basement directly below the posts. The wall is directly above a steel beam that runs the length of the house.

Anyway I put up two temprary walls, one on each side of the wall and went to work. I secured the header to the king studs and 4 by 4 posts with 8 inch bolts and 16d nails. Everything is level and plumb. I removed the temporary walls and everything was fine.

Then later that night I noticed that one ceiling joist appeared to have moved down a little, actually bending the drywall, causing a crease. Not a crack, but a crease. Since Sunday the joist hasn't moved at all. the other joists appear to be fine. This joist just happens to be supporting a second floor wall.

I talked to the structural engineer who said nothing is structurally wrong. tHe house was built in 73 and he says the joists have just conformed to the load-bearing wall and changing the structure causes the joists to settle a little. He said this particular joist has a little more load on it and may be warped or something and that's it. He says it's purely aesthetic and not to worry. He said the header I used is more than large enough to handle the load and if the joists are indeed resting on the header that's all that matters.

Anyway, have any of you had this problem? Does this settling explanation make sense? I've jumped up and down up there, no squeaking, and the joist hasn't moved in 5 days. I just want to make sure the structural integrity of the ceiling is still in tact.

Thanks!

Gary in WA

“I consulted with a structural engineer who did calculations and said 2 2 by 12 inch lvls”--- it’s either 1-3/4” LVL x 2 = 3-1/2” or 2- 2x12’s solid lumber joists ganged together. This is from an Engineer?

“He also suggested doubling up the king studs” ---- He said that?

“I secured the header to the king studs and 4 by 4 posts with 8 inch bolts and 16d nails.” ----Where, exactly, do the bolts go?

So far, all the info sounds bogus. 15’ joist span (X) 50# per ft. = 750#
(X) 9.5 span= 7125# Plus c.j.s, framing and drywall plus the 7125 = 8300# total dead/live loads 6x10 solid beam, #2, Df 1500fb carries 8500#, no way will 2-2x12’s work (they carry 5400#). 2- 1-3/4” x 9.5 = -12,000# http://www.parr.com/PDFs/LP%20LVL%201.9E.pdf

Either you or I need to check the figures again.......


And, Welcome to the forum!


Gary

__________________

gbrady

The engineer was from the company who actually designed the lvls. He didn't say 2 by 12 inch but I was simplifying. I know it's 1 3/4 by 11 7/8. Anyway I gave him the information he needed and he concluded that two of these beams would be plenty for a 9.5 foot span. The house is brick and it's got a truss-built roof.

I can't understand a lot of your response, but what do you think about the joists settling a little? Is this possible? What size header do you think I should have installed?

gbrady

Just got a response from Tim Carter who says the engineer is "spot on. No issue here." Who's correct, you or Tim?

Talbot3

The engineer's design is ok.

Using Gary's loading of 874#/ft:

M = 9860 # ft
V = 4150#
Using (2) 1.75x11.875 lvl
bending stress= 1350
Shear stress = 150 psi
Both of these are below the allowable in Gary's link

Daniel Holzman

I assume you paid the engineer for the report, and I am not interested in second guessing a professional engineer's report given that he presumably saw the site, and nobody on this forum has. As for settlement of joists, this is certainly possible. You removed a wall which the joists were presumably resting on, and replaced the wall with an LVL header, which was presumably straight.

It is entirely possible that the joist in question was originally shimmed against the top plate of the wall, and when you removed the wall, the shim is gone. When you installed the LVL's, there could have been a small gap between the joist and the top of the LVL where the shim used to be, and if you did not shim the gap between the LVL and the joist, then of course the joist would settle until it contacted the LVL once the temporary supporting walls were removed. When I did a similar project, I left the double top plate of the old wall in place, and installed a steel beam underneath the plate. The plate was far from flat, so I shimmed the gap between the plate and the beam, which eliminated any movement of the joists above the beam.

In some cases, especially if you do not have the room to keep the old top plates, you are likely to encounter movement of the joists when they settle against the support beam. Generally not a problem if the beam is properly sized, except that you can crack some plaster.