Thread: I Beam Pockets in Poured Concrete Foundation

I just want a sanity check to see if my concern for the structure of the house we are building is justified. I have two seperate I Beam concerns with the current construction.

1. The first concern is that an 8 inch wide steel I beam is resting approximately 1 and 3/4 inch outside of the poured concrete foundation pocket. Said differnetly the beam is not centered on teh pocket, but instead is pushed to the edge of the pocket, such that 1 and 3/4 inches of the bottom of the I is hanging as a lip. The reason that the builder (who is generally doing a good job, has an excellent reputation and who I generally trust) said that the reason for the overhang is that they moved from a thinner wood beam to a larger steel beam. There is room to move the beam futher in the pocket, but I assume this is not being done b/c the load of the house should be centered. My question is whether it is generally acceptable to have 6 1/4 inch of the beam resting on the foundation while the other 1 3/4 inch is hanging off.

2. I have attached a picture of this one to make it easier, but in this case, the beam, a thinner beam that the one used in #1 above, is not "deep" in the pocket. It is resting on steel shims, which I believe is acceptable, but my concern is that it is not deep enough in the pocket to be safe. There appears to be approximately 2-3 inches of overlap on the concrete pocket.

I understand that I can't get a definitive answer here, but really just want a gut check as to whether a stamped letter from our builder's engineer should be enough, or whether I should seek indpendent review. I don't want to create an issue where there shouldt be one, but I also want the house to be safe. Any thoughts would be appreciated.

beam.JPG

Others may have different standards that they can quote, but I think it generally accepted that the minimum bearing should be 3 -3.5 inches.

Originally Posted by Raymond Wand

Others may have different standards that they can quote, but I think it generally accepted that the minimum bearing should be 3 -3.5 inches.

Thank you, Raymond.

Originally Posted by Don Shelkey

I just want a sanity check to see if my concern for the structure of the house we are building is justified. I have two seperate I Beam concerns with the current construction.

1. The first concern is that an 8 inch wide steel I beam is resting approximately 1 and 3/4 inch outside of the poured concrete foundation pocket. Said differnetly the beam is not centered on teh pocket, but instead is pushed to the edge of the pocket, such that 1 and 3/4 inches of the bottom of the I is hanging as a lip. The reason that the builder (who is generally doing a good job, has an excellent reputation and who I generally trust) said that the reason for the overhang is that they moved from a thinner wood beam to a larger steel beam. There is room to move the beam futher in the pocket, but I assume this is not being done b/c the load of the house should be centered. My question is whether it is generally acceptable to have 6 1/4 inch of the beam resting on the foundation while the other 1 3/4 inch is hanging off.

2. I have attached a picture of this one to make it easier, but in this case, the beam, a thinner beam that the one used in #1 above, is not "deep" in the pocket. It is resting on steel shims, which I believe is acceptable, but my concern is that it is not deep enough in the pocket to be safe. There appears to be approximately 2-3 inches of overlap on the concrete pocket.

I understand that I can't get a definitive answer here, but really just want a gut check as to whether a stamped letter from our builder's engineer should be enough, or whether I should seek indpendent review. I don't want to create an issue where there shouldt be one, but I also want the house to be safe. Any thoughts would be appreciated.

beam.JPG

Since the load on beams can be quite large the concern with either of these conditions is that there could be a shear failure in the concrete below the beams. That is where the concrete would break off at about a 45 degree angle from somewhere below the bear out to the inside face of the wall. If you receive a stamped letter from an engineer than he is putting his (or her) license on the line stating that it is o.k. I would accept that.

Alternatively a steel column could be installed and bolted to the beam with a proper footing for the column.

It is wrong. I can understand why they set it and why the beam is short. But it is still wrong. I would agree that cracking the floor and setting a footer with a column would be a cost effective solution, though possibly not for the owner since it will be set into the room on the wall facing.

Originally Posted by Garry Sorrells

It is wrong. I can understand why they set it and why the beam is short. But it is still wrong. I would agree that cracking the floor and setting a footer with a column would be a cost effective solution, though possibly not for the owner since it will be set into the room on the wall facing.

Why not just weld on a piece?

Originally Posted by Vern Heiler

Why not just weld on a piece?

You would still need a SE Letter with that as a remedy, the beam and everything on it would need to come down to weld.

Originally Posted by Billy Stephens

You would still need a SE Letter with that as a remedy, the beam and everything on it would need to come down to weld.

SE letter yes. Everything come down, maybe not. I've seen mig welds done in some pretty tight and flammable locations. To weld on a flat plate to the side of the beam with steel shim under the end that lands on the concrete would not be all that difficult.

Originally Posted by Vern Heiler

SE letter yes. Everything come down, maybe not. I've seen mig welds done in some pretty tight and flammable locations. To weld on a flat plate to the side of the beam with steel shim under the end that lands on the concrete would not be all that difficult.

If the SE signed off on it.

Originally Posted by Billy Stephens

If the SE signed off on it.

Thank you for all of the replies. Your expertise is greatly appreciated.

I requested that the builder bring his structural engineer to the site and prepare a stamped letter stating that the design, as built, is structurally sound and meets all applicable codes.

I measured the bearing on the beam shown above when I got home and it was 2.5". Today, when the SE and the builder was on site, they moved it back into the pocket a bit. I will measure when I get home, but I almost guarantee, they moved it to 3" to be up to code. For that issue, everything that I read (including the applicable code) seems to indicate that 3" is acceptable. If I get the SE Letter + it is at least 3", I will drop the second issue going forward, although I may alert the township building inspector to get a second look.

I havent found anything with respect to the second issue as to how much "horizontal bearing" there must be. I took a picture of the other issue to make it a little easier to explain. The bottom line is that if a SE is saying its OK and it passes inspection, I think that will have to do. I may request that the pockets be filled in with concrete so it doesn't look like ****, however. Picture of the first issue is attached for those that are curious.

other beam.JPG

Attached is a picture of the same beam that I originally posted, but this time after it was pushed back further into the pocket by the builder. Looks to be > 3 inches.

update.JPG

Originally Posted by Don Shelkey

Thank you for all of the replies. Your expertise is greatly appreciated.

I requested that the builder bring his structural engineer to the site and prepare a stamped letter stating that the design, as built, is structurally sound and meets all applicable codes.

I measured the bearing on the beam shown above when I got home and it was 2.5". Today, when the SE and the builder was on site, they moved it back into the pocket a bit. I will measure when I get home, but I almost guarantee, they moved it to 3" to be up to code. For that issue, everything that I read (including the applicable code) seems to indicate that 3" is acceptable. If I get the SE Letter + it is at least 3", I will drop the second issue going forward, although I may alert the township building inspector to get a second look.

I havent found anything with respect to the second issue as to how much "horizontal bearing" there must be. I took a picture of the other issue to make it a little easier to explain. The bottom line is that if a SE is saying its OK and it passes inspection, I think that will have to do. I may request that the pockets be filled in with concrete so it doesn't look like ****, however. Picture of the first issue is attached for those that are curious.

other beam.JPG

Attached is a picture of the same beam that I originally posted, but this time after it was pushed back further into the pocket by the builder. Looks to be > 3 inches.

update.JPG

If the top steel shim plate does not extend to the end of the I' beam, the bearing is still less than 3".

The biggest issue I have is, without proper concrete reinforcing steel that beam seat will likely shear off, especially one located at a corner.

Also would I be correct in stating that the shims are supposed to be welded to the beam? I have never seen shims welded, but that is what I have read somewhere.

Originally Posted by Raymond Wand

Also would I be correct in stating that the shims are supposed to be welded to the beam? I have never seen shims welded, but that is what I have read somewhere.

Shims do not need to be welded. The beam should be restrained from movement in some way. With a typical pocket the pocket is usually filled with cement. With a corner pocket that does not provide much support, but if the beam is properly attached to the floor system and columns then additional attachment may not be needed (that would be the engineer's call).

As I stated before, if the engineer calculates that the beam has adequate bearing to prevent a shear failure, then the bearing may be fine. If not, welding a thick shim to the bottom of the beam and extending the shim past the end of the beam may be a simple fix. Someone mentioned welding a short piece of I beam to the end. That would likely be difficult and not needed.

Originally Posted by Mark Reinmiller

Shims do not need to be welded. The beam should be restrained from movement in some way. With a typical pocket the pocket is usually filled with cement. With a corner pocket that does not provide much support, but if the beam is properly attached to the floor system and columns then additional attachment may not be needed (that would be the engineer's call).

As I stated before, if the engineer calculates that the beam has adequate bearing to prevent a shear failure, then the bearing may be fine. If not, welding a thick shim to the bottom of the beam and extending the shim past the end of the beam may be a simple fix. Someone mentioned welding a short piece of I beam to the end. That would likely be difficult and not needed.

In the last pic the I' beam has been extended into the pocket but the shim beneath it leaves 1" of the beam in the air. The simple solution now is to move the shim to the end of the beam.

I just happened to see my local "guru" and he said if it was his house he would reject it, but if he was hired for someone else's home he would engineer a fix for it.

Without knowing all the details such as how much weight, point loads, span, etc. here are some comments.

The beam shall rest a minimum of 3.5" into the pocket and have full bearing the width of the beam when on concrete. The outside inch of the concrete is worth nothing, so if the beam overhangs 1.5" it is really 2.5" of overhang. The problem with adding lumber on the edge to support the beam, second picture, is the possible lack of proper footing below, and wood also compresses differently compared to concrete.

Looking at the picture it appears the beams sits outside the middle 1/3 of the bearing surface, in this case, due to a corner pocket, causing more concern and some type of fix, or move the beam. Moving the beam should not be that big of a deal as the joists seem to extend past the beam to the right.

Also, don’t be surprised when you see a vertical crack in the future from the beam pocket to the floor.

Originally Posted by Mike Kleisch

Also, don’t be surprised when you see a vertical crack in the future from the beam pocket to the floor.

Vertical cracks at beam pockets are pretty common (not that common near a corner though). These cracks are typically shrinkage cracks that occur at this location due to stress concentrations at corners (similar cracks are common below windows). I mention this so that someone does not think that these cracks are due to the the weight of the beam.

Thanks so much for the replies. Everyone's guidance is really appreciated. My thoughts are to do the following:

(1) Review the SE Letter to ensure that "as built" the construction is sound.
(2) Alert the county building inspector of my concern so that he can take an appropriate look at the structure.

If the SE letter and the county inspector are both OK with the construction, I will defer to their judgment. If the inspector has an issue or if the SE Letter comes back with significant qualifications, then I will hire an independent SE to analyze the situation and make a recommendation to reject or repair the issue.

If the SE sends a letter, there is little the building inspector can do about it. He cannot override a SE; he can ask for calculations and documentations but cannot override a SE.

Originally Posted by Darren Miller

If the SE sends a letter, there is little the building inspector can do about it. He cannot override a SE; he can ask for calculations and documentations but cannot override a SE.

At least the SE is accountable for his opinion. Generally building inspectors are not accountable for their opinions.