Basement walls in a Flipped house

[Ben29]

I got a call from a guy last week who is selling a house that he remodeled. He was flagged by a home inspector because there is a horizontal crack in the CMU wall in the basement. So to clarify, the client said that the basement was finished 'poorly' when he bought the house. He said he gutted the basement and redid everything. It does look great. There was only (2) areas of the basement that didn't get drywalled: the area under the stairs and a corner where they keep the water heater.

The area under the stairs is where the inspector saw the crack. So I tell the client that I would need to remove portions of the drywall throughout the basement to inspect the entire wall. He is OK with that. So the area under the stairs is where the crack is the worst (1/4 inch). I checked several other areas in the basement. The CMU wall is moist and the mortar is dark-colored and crumbling in some areas. But the horizontal wall crack dissipates to 1/16".

There is no drain tile or sump pump in the basement at all. And like I said, this basement is totally finished. The house was built in 1969.

I am really struggling with this. The area that has the 1/4" wide horizontal crack is only about 4ft wide. I was going to specify W4 steel I-beams (installed vertically) to reinforce the wall. Normally I would tell them to install an interior drain tile and a sump pump, but this guy would need to rip up the entire basement that he just finished!

 

[SWComposites]

What is the drainage situation on the outside of the house where the crack is? Downspout there?

LOL, and I've owned and sold houses with far worse cracks in the basement walls.

 

[Ben29]

The homeowner told me that the previous owners did not have gutters and it was just a mess. The current owner installed gutters and downspouts that move water away from the foundation.

The photo in my first post is where I picked out the existing mortar with a screw driver. Here is the photo of the crack under the stairs:

 

[RPGs]

I sympathize with you--this is not an easy choice on your part. The basement looks great. It's really tough to come across these horizontally cracked CMU walls--it always feels like I'm telling homeowners they have a terminal illness.

I usually spec the vertical steel section foundation wall reinforcement, particularly for wall sections with larger cracks, as opposed to smaller cracks dispersed along the wall's height, which may be an indication that some wall reinforcement is present and carbon straps may be an option.

I would likely agree that more investigation should be undertaken to determine the extent of cracked foundation walls. The extent and severity of cracks may also inform you of how exterior drainage work should be targeted to prevent excess stormwater-related water from coming saturating the retained soils & coming into contact with the foundation walls.

Barring groundwater flow conditions, I don't think an interior drainage course is necessarily required as part of the foundation wall reinforcement work, assuming all exterior regrading and downspout drainage efforts to convey surficial stormwater away from the foundation are exhausted. Of course, if the existing finished basement walls do not have an air gap or other moisture barrier, they can likely expect moisture from the foundation walls to adversely affect the interior finishes.

 

[Ben29]

RPGs: Thank you SO much!

Here is a photo of the wall encapsulation method used. Thin plastic sheeting.

 

[Ben29]

I don't want to make him do more than he has to. But, I have seen block walls fail before and I don't want to be on the other end of that phone call. I don't know what I need to specify in order to legally cover myself.

 

[RPGs]

Ben29, your concerns about the block walls are warranted--I too have seen them fail. I recommend you focus on structural integrity and safety over all other considerations.