Jack posts on basement slab

Hello all,
Did a mock inspection today on an older home. “temporary” Jack posts on double 2x4 blocks another directly on the basement slab and another on a brick. In other words no poured concrete footing for them to be resting on. In that case a permanent steel post (Lally column) would be better to use if a footing were to be poured. You see these so called temporary jack posts a lot in basements in older homes here. Temporary becomes permanent it seems.
Calling out temporary jack posts directly on the slab or on blocks without footings in the report and recommending a structural engineer further evaluate?
Working on my reporting narrative.
Thank you.

Pictures would help A LOT. Some steel posts are temporary and some are rated to be permanent.

Footings under a slab? Yeah, that’s always the million dollar question. My contract specifically states I can’t identify the presence of sub-grade footings. This is one of those examples of where we are there to evaluate performance. Is the post (or metal column, etc.) breaking into the slab? If not, it’s performing as intended and I generally move on and don’t cite a defect.

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Personally, I will only call them out if they’re being used as part of the primary support system, such as under a beam. In many older homes the posts were wood that were/are subject to moisture and or WDI damage and were subsequently replaced with “temporary” posts.

On the other hand, many times they are installed to add extra support if there is excessive bounce in the floor in an area, or if someone is planning on installing something heavy on the floor above that area.

It’s your call if you want to recommend an SE for further evaluation, but I would be recommending a qualified Contractor to make corrections as needed only if they were being used as part of the primary support system. But it’s important that you stay within your comfort zone when writing inspection reports.

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Thanks Matt.


Holding up in part, a beam next to the basement stairwell opening which is up against the foundation wall.

Thanks Kevin, it is in part holding the beam next to the stairwell opening. This being a mock inspection and knowing the person, I’m going to go back and take photos of each jack post and the beams. I know 2 jack posts holding the center floor beam are on foundations and 2 have been seemingly added for extra support that aren’t. There isn’t any visible cracking of the slab or supports under the posts at this time. Apart from the attached photo of the post on 2x4’s the slab has some cracks around it.

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Be sure to get some “overview” photos of the full area these posts are situated in, the full area supported by these posts. Close up pics are helpful, but mean little by themselves in the scheme of things.
Remember, we’re not there in person, so you need to show us what we can’t see.

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Thanks Jeffrey, this being a mock inspection I’m going back to take wider photos of the beam for context. I find these posts to be frustrating because you see them here a lot and they’re usually not supported, in my opinion properly. If it were supported on a bigger concrete pad I would be better with it as opposed to 2x4’s that are susceptible to moisture etc… I honestly don’t know why they even bother to do it like that.