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Post in Concrete Door Opening

Post in Concrete Door Opening

Post in Concrete Door Opening

(OP)
My family is looking to install a new back sliding door. Upon removing the paneling, we've discovered a column that was unforeseen within the wall. I am investigating the plausibility of removing the post so the door can be installed.

This is a basement door, so it is below the house within the foundation wall. It's difficult to tell but it looks like this was a poured opening and not a saw cut, and we aren't sure about the rebar within the header. I am most concerned with the crack that is directly above the post, as it appears the previous owner could have noticed it and installed the post after the fact although we have no way of knowing. Throughout the majority of the house (and in a different foundation wall) more than enough rebar has been used. The span of this opening is about 8'.

1. I would assume so, but is it dangerous to remove the post without knowing the rebar presence in the wall above the opening?
2. Does it even seem worth it to investigate removing the post in the first place, or is it a lost cause?
3. What would be a ballpark cost to receive a 'seal of approval' from a single practitioner in the area, assuming it would be deemed safe? Located in OH, USA

I appreciate your help. These are the only photos I have at the moment, but if there are any requests I can get more photos.









RE: Post in Concrete Door Opening

Great questions and a great topic to cut your teeth on as a new member of the structural engineering profession.

In short answers to your questions:

Quote (cec17)

1. I would assume so, but is it dangerous to remove the post without knowing the rebar presence in the wall above the opening?

1) Yes. While catastrophic failure is unlikely (but not impossible) I agree that crack and the span length gives me pause. Removing it could likely cause a deflection in the the wall opening causing issues to finishes and openings above, or other issues (more cracking, etc.). In short, someone put that column there for a reason. Until you know why I wouldn't remove it.

Quote (cec17)

2. Does it even seem worth it to investigate removing the post in the first place, or is it a lost cause?

2) It's never a lost cause, the only limits are time (both the clients and yours, thankfully those people are the same person in your case), money (it's always money), and your abilities. Shouldn't cost much money to investigate and resolve, your time I assume is available as needed for this project, and it sounds like you'll farm out any work that's beyond your abilities, which is wise.

Quote (cec17)

3. What would be a ballpark cost to receive a 'seal of approval' from a single practitioner in the area, assuming it would be deemed safe? Located in OH, USA

3) Depends on the cost of your local engineers but if it were me I'd bill no more than an hour on site, an hour or two of calcs and report writing, plus travel time and other expenses. Say not more than $400 at most, possibly even less as working for an engineering grad would eliminate 99% of the common hassles I'd expect from a typical small residential job. Make sure you mention that to anyone you get a price for, it will make a difference in the cost. Find a small engineering firm, big firms will just give you an inflated cost as they likely don't want to deal with such a small residential project.

If it were me in your place I'd find a single person structural engineering firm or concrete specialist who has a high-end rebar scanner. One that can roughly determine bar size and depth. If this isn't available (or even if it is) get a cheap rebar locator (good tool to have anyway), find any rebar running horizontal above the opening, and demo a very small access hole under mid-span to confirm the bar location and determine the size. Take dimensions of the opening and try to determine the spans and dimensions of any framing or load bearing walls that put load on this opening. Take plenty of pictures and bring all this to a local structural engineer. Get written prices from at least 3 of them and pick one you think is best (not always the lowest cost). Work with him or her to determine the capacity of the wall (reinforced or not) and determine if it's safe to remove or if a new header needs to be installed.

If a new header is needed you can actually install a temporary header first. The way I've done it is get two scrap steel channel sections that can span well past the opening. Drill holes through the wall and matching holes on the channels. Bolt the channels up on either side above the opening as high as possible. Sawcut the wall and install a new header of either channels or steel angles with the flanges into the cuts. Grout the new header in place and remove the temp. header. Obviously, you'll want to have the structural engineer help you run the numbers on the header sizes and install procedure.

When you're all said and done you've hopefully impressed the structural engineer you hired. Submit a resume and job application.

Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
https://www.facebook.com/AmericanConcrete/

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