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mathew stouffer
07-07-2008, 08:10 PM
The ceiling of this storage area was sagging significantly. Above the area is a concrete patio. Is this from a lack of support when the conrete was poured.

Rick Hurst
07-07-2008, 08:16 PM
I would sure think so. Where are the supports?

Don't think I would have stood under there that long to even get the photo.

rick

Jerry Peck
07-07-2008, 08:16 PM
Is this from a lack of support when the conrete was poured.

Could be, but I doubt it, that would have been caught and corrected.

I'm guessing the supporting structure is over spanned for the load placed on it.

"Above the area is a concrete patio."

Concrete patio for what? A bar? Night club? (Thinking that it may be overloaded at special occasions.)

One question, though, was the patio above flat or dipped at that area?

If dipped, my guesses might be correct.

If flat, has the slab been "leveled" from time to time? If yes, each "leveling" simply adds more weight, causing it to sag more, which requires "leveling" again, which simply adds more weight, etc.

If flat and not leveled, then it might be from original construction - but that would be at the bottom of my list of things to try to figure out about it.

mathew stouffer
07-07-2008, 08:22 PM
Above is a "step up patio" with a canopy entry. No cracking, sag, or sign of previous repairs were noted. The house is two years old. The sag in the ceiling was enough to deflect that 2x4 in the left of the photo. The ceiling in the photo is under the canopy entry. There was also some problems with the suspended garage slab.

Jerry Peck
07-07-2008, 08:41 PM
Oh, single-family front porch. Why didn't you say so in the first place? :)

Yes, it could have been from original construction.

Now, though, the question becomes:

- was the metal 'just' serving as a form for the concrete pour, or,

- was the metal 'also' serving as structural support for the concrete?

I don't know. You would need to look at the engineering. I think there is a problem, but ...

... calling Brandon ... Brandon ... are you out there?

mathew stouffer
07-07-2008, 09:17 PM
Thanks Jerry. I think the metal was used as a form but it also appears some late movement may have occured. We will see what the contractor says.

Thanks

Gunnar Alquist
07-07-2008, 10:35 PM
Matthew,

DId you bang on the underside of the metal? If it has a solid sound, it would indicate that the weight of the wet concrete during the pour caused the sag. Like JP implied, is it going to stay put?

mathew stouffer
07-07-2008, 10:41 PM
Gunnar,
That was the first thing I did and it was "rock solid" just like the show.

Jim Luttrall
07-07-2008, 10:44 PM
Could be, but I doubt it, that would have been caught and corrected.



Jerry, think about that statement, then tell me what planet that happens on:D

Brandon Chew
07-08-2008, 06:34 AM
Oh, single-family front porch. Why didn't you say so in the first place? :)

Yes, it could have been from original construction.

Now, though, the question becomes:

- was the metal 'just' serving as a form for the concrete pour, or,

- was the metal 'also' serving as structural support for the concrete?

I don't know. You would need to look at the engineering. I think there is a problem, but ...

... calling Brandon ... Brandon ... are you out there?

There's not much for me to add. That is the key question. My GUESS is that the steel serves as the form and support for the slab. On a residential job like this one, I doubt that the slab would be engineered to be self-supporting over that span. The sag in the corrugated steel weakens that support.

It would be beyond the scope of a HI to determine whether it is ok as is, or if repairs are necessary. I would document my observations, explain why I'm concerned about them, and recommend evaluation of the slab and its support by a structural engineer. As a potential buyer, I wouldn't accept an opinion on something like this unless it was stamped by a PE. That written opinion and PE stamp will be very valuable when it comes time to sell the home to the next buyer.

Based on the comments in the thread I was ready to conclude it was probably built with that sag, but then Mathew also made the following comment, which I put in bold.


Thanks Jerry. I think the metal was used as a form but it also appears some late movement may have occured. We will see what the contractor says.

Thanks


What were the observations which lead to that conclusion?


Above is a "step up patio" with a canopy entry. No cracking, sag, or sign of previous repairs were noted. The house is two years old. The sag in the ceiling was enough to deflect that 2x4 in the left of the photo. The ceiling in the photo is under the canopy entry. There was also some problems with the suspended garage slab.


What kind of problems?