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Some background: previous owners poured a new foundation and moved the house over to the new basement about 14 year ago.

I've been in the house about 8 years and just noticed today while starting to re-do our basement that one of the main beams is resting on an angle iron because it was too short to reach the other end of the foundation.

I have 2 main beams in the house. I'm not sure if that makes this OK. What can I do here? This seems insane. How could anyone think this was the right thing to do?

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    The cheapest would probably build a footing under it(structural engineer job) and place a post.
    – crip659
    Commented Jan 28 at 21:22
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    Are there epoxied anchors, wedge anchors, etc. on the opposite side to stop it from rolling down at least? Even then, that's still a problem.
    – popham
    Commented Jan 28 at 21:25
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    The worst part is when someone does something like that, everything they did now must be examined. Commented Jan 28 at 23:20
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    Thanks @crip659 - most likely the direction we will go. Calling an engineer tomorrow morning. Commented Jan 29 at 1:18
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    It looks like the bottom wooden block has been thinking about splitting. If it did it would all collapse instantly. It's lasted 14 years BUT knowing how Murphy works, adding an ACRO JACK while the engineer prognosticates may be wise. Commented Jan 30 at 0:24

1 Answer 1

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That's a job for a local engineer. He'll need to figure out the demand on that connection based on whatever is going on above its joists (load bearing walls, columns, etc.). He'll probably extend the beam by 3" or 4" with lag screws and a chunk of steel or wood. A chunk of 4x6 lumber sounds easiest for installation if it has the strength, but that could be suboptimal if you want to finish the space later.

Throwing two chunks of 2'-0" L3x2x3/8 steel angle at it (one chunk on each side of the beam), a 10,000# strength is easily obtainable with correct detailing. L3x2x1/4 actually works for the 10,000#, but it's close enough that I would spend the extra 10 USD. I can't say if 10,000# strength is enough, but supposing it is, my biggest worry would be getting adequate quality for lag screw installations (and, if you're stuck with Hem-Fir or SPF, getting sufficient bearing capacity for the steel on top of the wall's 4x4). As insurance against poor quality, I would want a couple bolts plus plate washers through the beam's plies in the neighborhood of critical lag screws.

That 10,000# is an Allowable Stress Design number, where you would compare it directly with the load derived from dead load plus live load (and hopefully no additional loads from the roof, for instance). Optimistically, the check is just Area×(10psf + 40psf) ≤ 10,000#. There's an alternative design framework called Load Resistance Factor Design that has a higher strength (and higher demands) to reach similar designs in your case, otherwise I wouldn't bother qualifying the 10,000# as an Allowable Stress Design number.

If you're interested in where the 10,000# came from: https://i.sstatic.net/FFBYy.jpg

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  • +1 for the work sheet :-). At least. Commented Jan 30 at 0:18

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