A new beam question

Originally Posted By: dfrend
This post was automatically imported from our archived forum.



Hope you all can give me some help on this one.


I went out yesterday on a new home being built. The framing is mostly done, some rough electrical, some plumbing, etc. While inspecting the basement, the support beam caught my attention. It is a steel I beam spanning about 35 feet. One end rests on a notch in the right side foundation. the other rests in a notch on a part of foundation sticking out that appears to be there just for the beam. By notch I mean It looks like a cut out of the foundation above ground level just for the beam.

What caught my eye was ate the one end you could walk behind the wall holding it in an offset of the basement and the end of the beam was not supported by the wall. It was resting on some broken brick pieces and they were just filling in some concrete patch to make it look as if it runs right into the wall. Now the middle of this beam is solidly held by two steel post spaced equally apart. My question is, does this beam need to be supported at the ends or is it sufficient to have it supported only in the middle?

At this point my recommendation to my client is going to be to either get a building engineer to see it or have the builder sign off on it saying it is structurally sound to put the burden on them. Please offer your advice. Sorry no picture to help. ![icon_question.gif](upload://t2zemjDOQRADd4xSC3xOot86t0m.gif) ![icon_question.gif](upload://t2zemjDOQRADd4xSC3xOot86t0m.gif) ![icon_question.gif](upload://t2zemjDOQRADd4xSC3xOot86t0m.gif) ![icon_question.gif](upload://t2zemjDOQRADd4xSC3xOot86t0m.gif)


--
Daniel R Frend
www.nachifoundation.org
The Home Inspector Store
www.homeinspectorstore.com

Originally Posted By: jpope
This post was automatically imported from our archived forum.



Daniel,


Typically, steel beams have much greater strength than wood beams. In many cases, mid-span supports are an acceptable practice. However, you have no way of knowing where the intended bearing points should be unless you are an engineer. A blue print review may give you an indication of the required support if this is within the scope of your inspection.

Not having a picture to look at leaves me in the dark as to the potential load on this beam, but in any case, your recommendation for evaluation by a structural engineer is prudent. At the very least, I would recommend a qualified contractor to review the blue prints to verify proper support to the beam.


--
Jeff Pope
JPI Home Inspection Service
"At JPI, we'll help you look better"
(661) 212-0738

Originally Posted By: mpetner
This post was automatically imported from our archived forum.



Most house main beams are designed, for the most part, to be simply supported beams. That is, to have each end of the beam resting on a support, usually the foundations walls. And of course, there are intermittent columns to provide additional support and to limit deflection. If what you?re saying is that one end of the beam doesn?t look like it?s being adequately supported at one end, then it probably hasn?t been built the way the designer intended it to be. It?s difficult to say if whether or not this might be a problem because the homeowners may never load up that section of floor to the point that excessive stresses would be introduced in that part of the beam.


Then again, this may have been designed to be some sort of cantilever beam. Hard to tell without having the contract documents (plans and specs) . In any event, lateral support for the beam to prevent rollover may not be sufficient from what you?ve described.


Originally Posted By: rmeyers
This post was automatically imported from our archived forum.



Dan,


From the scenario you are describing, I would say that yes, the end of the beam should be supported. The issue of shimming the beam to the proper height with an appropriate materials is often a problem. The use of masonry components in conjunction with a non shrink grout is probably one of the more common practices found in residential construction and in general is acceptable. Lateral support can be gained by building up masonry or grout around the beam but care needs to be taken as with wood beams to leave room for movement of the beam so it does not damage the wall when it's length expands and contracts. ( This is with respect to simple residential beam systems. If rigid connections are required due to a special design criteria, then by all mean, the architect's or engineer's details should be strictly adhered to!)

Steel shims are also often used for support. In all cases, there should be at least 3-4" of beam bearing over the wall and at least a 4" masonry or concrete wall thickness. (I'm sure there are probably a wide assortment of items that some of our fellow inspectors have seen used as shims.)

Wood shims, although least desirable, are also often seen. They tend to crush and compress, and may contribute to settling problems if they are too thick and have compressed excessively. The wood shims are often not properly protected from termite access and may be subject to moisture exposure.

As is so often the case in our profession it is a judgement call as to the adequacy of a detail unless blatant failure is in progress. With this in mind , when issues like this arise sometimes it may be wise to question the contractor and/or consult with the local authority in order to substantiate if our concerns are valid before alarming the homeowner with additional professional analysis.

I recently did a new construction inspection where several trusses were improperly used and some additional wood gusset plates were applied in questionable locations. With a couple of calls to the contractor and the truss manufacturer I was able to document that the adjustments were actually re-engineered by the truss company and the repairs made on site by the truss company personnel. (Copies of the stamped documentation were forwarded with my report.)

As an inspector it doesn't hurt to have a good working relationship with the local authority and be willing to communicate with builders.

Just a few additional thoughts from an old contractor / inspector!!! ![icon_biggrin.gif](upload://iKNGSw3qcRIEmXySa8gItY6Gczg.gif) ![icon_biggrin.gif](upload://iKNGSw3qcRIEmXySa8gItY6Gczg.gif)

Have a GREAT DAY!!


--
Russ Meyers

Originally Posted By: roconnor
This post was automatically imported from our archived forum.



rmeyers wrote:
Dan, As an inspector it doesn't hurt to have a good working relationship with the local authority and be willing to communicate with builders.


Excellent statement Russ! Add building designer to that list.

Usually steel beams always count on the end walls for support. So it's pretty likely that beam isn't adequate without end supports ... but, unless there are signs it's deflecting, it's still a shot in the dark. IMO, there is no need to call in a design professional at this point (contractors shouldn't be evaluating framing), since you could talk to the builder, or ask the AHJ or designer real quick.

But talking to builders about what you observed first goes a long way towards reaching the ultimate common goal ... a quality house for your client. Builders usually appreciate the oppurtunity to correct something, instead of reading it in your report or hearing it from your client.

Quote:
Example: Observed apparent inadequate end supports for main steel floor beam ... bla bla bla. Builder indicated beam supports were already scheduled to be corrected. Verification of beam support corrections recommended.


Mike ... nice to see another PE on the board.


--
Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee

I am absolutely amazed sometimes by how much thought goes into doing things wrong

Originally Posted By: psabados
This post was automatically imported from our archived forum.



Mike & Robert


Concerning the beam pocket formed by the foundation walls, how wide should the width of the pocket be in relation to the beam itself? I've seen pockets almost three times the width of the actual beam.

Also how should the beam pocket be treated or finished?

I've seen beams sitting tight in a small pocket, centered in the pocket with 2x4's to bricks installed to prevent roll or like in my home, the pocket filled with an epoxy type mortar fill. And, of course, just open and exposed pockets with no support to prevent roll. Any preferrences?

This is steel beam construction and not wood.

Paul


Originally Posted By: roconnor
This post was automatically imported from our archived forum.



The size of the pocket isn’t really important, as long as the beam is braced from rolling … which is required. The best thing is to fill in a conc wall pocket with brick and mortar.



Robert O’Connor, PE


Eagle Engineering ?


Eagle Eye Inspections ?


NACHI Education Committee


I am absolutely amazed sometimes by how much thought goes into doing things wrong

Originally Posted By: psabados
This post was automatically imported from our archived forum.



Hey Robert


Do you have a code to reference that, or is it just a judgement call? Im seeing more and more new construction without anti-roll bracing.

This would be a recommendation to fix on a regular resale inspection, but something that should be performed on a warranty to construction inspection. Unfortunately I do not own a current set of book

Thanks again

Paul


Originally Posted By: roconnor
This post was automatically imported from our archived forum.



IRC R301.1.2 sends you to IBC 2204, which sends you to AISC-ASD specifications for steel design. Section B6 of the AISC-ASD specs states:


"At points of support, beams, girders and trusses shall be restrained against rotation about their longitudinal axis"

Hope that helps.


--
Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee

I am absolutely amazed sometimes by how much thought goes into doing things wrong