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Our contractor suggests that we use steel beams restraints when we implement our egress window his explanation is:

"Because your foundation is so tall, I don't want to cut the egress without putting a vertical steel beam restraint on each side of the new window. Your foundation will be weakened after the cut. The foundation will break within 5 years because of the hydrostatic pressure on the west side. "

Does this make sense ... Our basement ceilings are 12 feet tall ...

Thanks

Paul

closed as off-topic by isherwood, Daniel Griscom, Machavity, ThreePhaseEel, Retired Master Electrician Apr 4 at 12:47

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    So, your contractor can see the whole job on site and you want us to make a decision or give relevant advice without even a photo or fag-packet drawing.... – Solar Mike Apr 1 at 15:58
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    You haven't told us what sort of foundation we're talking about, nor where you are (what earthquake risk you face). – isherwood Apr 1 at 16:05
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    Hello, and welcome to Home Improvement. A diagram might better help us help you; would you edit it into your question? Thanks. – Daniel Griscom Apr 1 at 18:00
  • I live in MIssouri/Kansas border and I was told heavy clay type soil I also live on a sloping lot which slopes down to a hill ... The house is very well built confirmed by a Structural Engineer ... – Paul Apr 1 at 21:03
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I agree with your contractor. A 12' pour is extreme (and awesome) for residential. You could take this to an engineer but why? It is really an opinion thing as the force on the wall is a relative unknown to the engineer. Some things that will effect or pressure basement walls -

  1. The dry and wet cycle of your soil. Soils like clay hold a lot of water and can expand.
  2. Given #1, the drainage right next to your foundation. A lot of foundations don't have a proper way to deal with #1. There are lots of systems that can funnel water by the house a few feet away.
  3. How packed the soil is.
  4. The amount of water pressure from underground water sources. I had a house where if you dug three feet down on one side of the house there was a stream and it would run for days after a rain. I simply diverted it with a faux wall before house corner.
  5. Frost cycles. With a rain and then weeks of freezing can probably do more damage than the reasons above.
  6. Earthquakes/movement.

My point is this isn't an exact science unless there is a deep analysis of your exact situation. An engineer is probably going off of local guidelines or load charts. Meaning he is giving an educated guess. The other thing is - given this opening what engineer would say don't support it? It is his/her butt on the line if it fails.

I treat this type of situation the exact same way I treat opening up load bearing walls. Over-engineer, and spend less money on engineers. To me adding vertical supports is a no-duh thing. You have a 12' pour and you want to ruin that by not putting in a few vertical supports? The cost not to do it will probably be half the cost of the beams/anchors. Also if basement doesn't have a door I would think about it given these costs.

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In my area, qualified engineers are required to review modifications to building structures. From my experience, if the contractor is worried about the strength of something, there is probably good reason to have it reviewed by an engineer.

Also a 12' high basement wall is no small item, openings place in it can cause issues if not done properly.

As Joe and others have mentioned, often times when placing new openings in existing concrete or cmu walls, two different load carry elements are compromised.

  1. Vertical Carry Capacity. This is where steel lintels are used to carry the wall above that was previously carried by the wall that is being removed.
  2. Lateral Load Carry Capacity. Basement walls are designed to carry pressure perpendicular to their surface. Be it from wind, soil, water, or seismic. Openings (full height or partial height) create a weakness that must be compensated for. Steel beams (running vertically from foundation to floor system above) can be used to support the weakness created by placement of a new openings.

Personally I would insist that a qualified professional review any modifications of this type. They can gather the necessary information (something we cannot do here), and make the correct judgement call. This way you can get your second opinion, check the contractor, and rest easy knowing that your home is going to be safe.

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Sounds like he's (your contractor) talking about lintels. In order to pick up the load of the brick or concrete above the opening steel lintels are installed.

Here's an example of a lintel installed at the time of the wall being erected

enter image description here

Allied Steel

A beam can be use instead of a lintel.

Edit, possibly lateral bracing with beams placed as posts?

enter image description here

Acculift Foundation Repair

If a contractor was suggesting that this should be done, it must be for a good reason. I could see how it can be precived as overkill, but as long as the price is reasonable I'd be good with it in my house.

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    OP specified "vertical", so I don't think this is about lintels... – Aloysius Defenestrate Apr 1 at 17:00
  • He said beams, beams are a horizontal member. Posts are a vertical member. I think the "vertical" he's talking about is the vertical load, which is addressed by a horizontal beam. I'm not sure as the question is a little unclear. I answered to the best of my ability based on the question and the above is my logical pathway to arrive at the conclusion. – Joe Fala Apr 1 at 17:08
  • Agree that the question isn't 100% clear. Maybe the OP can clarify. (BTW, Joe, I appreciate your contributions here. Please don't take my comment as criticism.) – Aloysius Defenestrate Apr 1 at 17:33
  • My initial thought was a lintel, as well, but, according to the OP's post, "vertical", "beam", and "each side of the window". 2 outta 3 says this is post-like, 1 outta 3 says beam-like. All in all, kinda confusing. – FreeMan Apr 1 at 18:55
  • Seems there may be a loose soil or high water table issue posing threat of damage from lateral pressure. In that case lateral bracing would be required. Still not a beam. I'm in a earthquake safezone so I don't know anything about how such a system would be integrated. I think maybe that's what the OP is referring to. Now I'm really interested in this question. Maybe they use I-beams placed vertically and fastened to the wall, slab and joists as bracing. I could see using maybe a w4 I-beam on either side tied in top and bottom. – Joe Fala Apr 1 at 19:14

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