House with Foundation Cracks 6

[Logan82]

Hi,

I am shopping for a single-family home. There is a house about 50 years old that interests me. However, it has a 5mm wide crack at the front and back. The crack may go from one side of the foundation to the other, but it is not possible to verify this without removing the floor, drywall, and insulation. The crack has spread on the exterior brick siding about 2 feet high, both at the front and back of the house. However, the crack has not spread to the interior drywall.

- What does this type of defect imply?
- Would it be relevant to request a quote to see if it would be appropriate to consult with an expert about underpinning the foundation and injecting the cracks? If so, is underpinning + crack injection a durable solution, or is it a temporary fix ("band-aid")?
- Could the fact that a house has been underpinned and injected scare off buyers? I am thinking about resale value in the future.

Sketch:

Photo of the crack at the front:

 

[jerseyshore]

One photo from a potato isn't going to be useful even in the slightest. It could be a failing foundation or nothing or someplace in between.

If you feel there is a structural concern you have to hire an structural engineer.

A potential buyer of a home sent me a few photos from a home inspection report last week, looking just like this. The photos showed a crack in the two blocks above a crawlspace vent opening. The buyer said what do you think? I said it looks like they took a block out to make the crawlspace vent and the block above cracked, not uncommon, they never put a lintel or any reinforcement over those things. They were in a rush to close and didn't really want to spend the money to have me go out there. I said listen I have to be in that town for another visit the next day, I'll give you a little discount, not really much I can do looking at two text message photos of screenshots of the inspection report. They said fine.

I walk around the side of the house and guess what, it wasn't just a crack over the vent opening. The entire left side of the foundation was broken and failing. The crack over the vent just so happened to be in the area where the foundation was falling into the lagoon. The buyer didn't know that. The home inspector didn't know that, but that type of failure I see weekly around here. I called him right up and said this was the best money you ever spent because you're going to need helical pile underpinning all around the left side. They took my report, got a quote for the repair, and got that money off on the house. Needless to say they were very happy spending a few hundred for my time and saving tens of thousands on that house.

Get an engineer.

 

[GEE8B]

Retain a licensed engineer to help navigate the issue, or have the homeowner retain one.

There is no way to know the extent or cause from what little you’ve shared, so any conversation about underpinning is premature and potentially irrelevant.

 

[phamENG]

Be nice to Logan. Check his profile - unlike the numerous freeloaders who make an account to get free engineering, he's been around a couple years. Looks like his specialty (if he has one yet) is industrial/ heavy civil. Probably a junior engineer in that space.

But Logan, if what I surmise is true, you wouldn't seek the advice of a residential SE to help you design a steel conveyor tower. Hire somebody who does this work daily. Since you are an engineer, they'll probably teach you along the way.

 

[Logan82]

Thank you jerseyshore for your answer. Your intervention gave an interesting outcome!

Thank you phamENG. You are correct, I am a structural engineer, and I have worked mostly in heavy civil. I have no experience in residential structural engineering. However, I am interested to learn more about this field. If you have any reference book to suggest, I would be really interested to take a look.

Being in a region with a housing crisis, houses sell in overbid. I have been advised that the seller may refuse my promise of purchase if I ask for advanced investigations.

I am leaning toward not purchasing this house after having seen this flaw, but before doing that, I want to investigate this flaw as much as I can to understand the magnitude of this problem. Also it is a learning experience for me.

Also, would it be useless to hire an engineer specialized in this field without opening the walls (gypsum and isolation)?

 

[phamENG]

the seller may refuse my promise of purchase if I ask for advanced investigations

Logan - I don't care how bad the market is, paying too much for a house you can't even investigate before you buy is not a smart move. Rent until the market is at least reasonable. That way, if the house purchased was a lemon, it's your landlord's problem.

 

[jerseyshore]

I hear a similar thing all the time because like many places in the US, the market is ridiculous in my area. People have to choose whether to waive all inspections or do their due diligence. I go to these houses with terrible foundations daily and regardless of what I find there is almost no negotiating room. I understand that because we searched for 2 years to buy a house around here.

Too risky for me to buy a house without getting it looked at thoroughly. Just too much money invested not only into the house, but also in potential repairs. I get the "we knew it had some issues when we bought it" all the time, but it turns out it's a $50k issue.

But back on topic, you can definitely hire an engineer to look at the foundation and anything else in the house. Seeing behind the sheetrock isn't going to help much when it comes to foundation issues.

 

[dik]

The crack appears to be uniformly wide, and likely extends below grade. Can you check the interior basement walls? The wall appears to be light coloured. In some areas, higher strength concrete has a more grey colour. Could be a weak concrete mix. Crack is vertical, which is generally much better than horizontal ones.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Logan82]

Logan - I don't care how bad the market is, paying too much for a house you can't even investigate before you buy is not a smart move. Rent until the market is at least reasonable. That way, if the house purchased was a lemon, it's your landlord's problem.

Considering that immigration in my region will triple by next year, I'm not sure that the market will become reasonable in the short term. If I can't inspect it, I think that one way to see it, is to check if this a good investment even if the worst case scenario happens with this flaw. In my case, this worst case could maybe imply the following:
- replace the basement interior due to molds caused by the the presence of water due to the cracks
- underpinning due to settlement issues
- injecting the cracks to seal the foundation

But back on topic, you can definitely hire an engineer to look at the foundation and anything else in the house. Seeing behind the sheetrock isn't going to help much when it comes to foundation issues.

By opening the wall, it could maybe tell me if the crack continues in the slab. Another thing is that if there is a crack, and the water goes through, maybe there is mold behind the sheetrock. I would see that by opening the sheetrock.

Can you check the interior basement walls?

Here is an image of the concrete foundation, but from the inside. Note there is efflorescence.

Here is a photo of the concrete balcony at the front of the house. The balcony is just on top of the crack I have shown in my first post. The cracked propagated through it.

But the crack didn't stop there, it went through the brick.

Here is the crack on the other side of the house (at the back of the house). The crack was repaired 10 years ago, but the buyer gave me no bill (so I have no warranty).

 

[dik]

Efflorescence is generally a moisture related issue; what is the groundwater table like?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[JAE]

Hire an engineer if you are sincerely interested in this.
Answers given here, by good engineers mind you, could be very wrong as they are based on a few photos.

 

[Logan82]

How can I get information on the groundwater table? I would say that the groundwater table was fairly high before the construction in this neighborhood, judging by how the forest land looks like not so far away. But I feel that the residential development drained the land quite a bit. There is a small river at about 500 m from this house. The basement floor is about 10 meters higher than the top of the water in the river in normal condition according to Google Earth.

The ground in the region has a lot of clay in it.

 

[jerseyshore]

Oh I thought you meant sheetrock like on the first floor.

Even with those additional photos, it's just hard to get any idea of what's going on. Could be some shrinkage cracks, some minor settlement, or something more serious.

The only thing that I can tell you for certain is that this was previously patched and those cracks have opened back up, which would seem to indicate continuing movement.

Like I said above, you have to decide between just wanting this house no matter what and dealing with the potential consequences later on or get the structural evaluation and risk being passed over. For me structural issues can be such big money that it's not worth the risk, but I deal with people in your similar situation constantly that are buying the house regardless of what I find/recommend.

 

[jhnblgr]

Concrete appears to be deteriorating based on the colors and texture. If allowed I would check to see if it flakes off or breaks easily. I have found some houses were built with poor quality concrete that you can pull bits off by hand and with a hammer easily break chunks out of. Look at the old aerial photos see what the are looked like before the house was built, was there a wet land or a low spot where they might have paced fill. Differential settlement could be the cause or lack of reinforcement. I looked at a foundation for a town because a home had over a hundred cracks in the foundation without even having a building on it yet. On Instagram the builder had posted videos of their work and in that case they built on topsoil, stripped the walls too fast and likely had too much water in the mix. On top of all that the engineer had provided a design that did not meet code and failed to specify construction joints. Do your homework and ask questions. Foundation issues are hard to fix and expensive.

 

[CrabbyT]

Vertical cracks are usually a result of differential settlement (i.e. one side of the crack settled more than the other, foundation cracked to accommodate). The question is, has the settlement stopped? That's not for me to say, but you could contact a geotechnical engineer and ask them what it would cost to look at it and to provide recommendations to stabilize the soil if necessary.

Horizontal cracks are bad news. They imply that the wall isn't capable of withstanding the pressure from the soil bearing inward.

 

[Logan82]

Look at the old aerial photos see what the are looked like before the house was built, was there a wet land or a low spot where they might have paced fill. Differential settlement could be the cause or lack of reinforcement.

There was a wetland there before the construction.

The question is, has the settlement stopped?

I agree, that's the 100 000 $ question. But I would say that jerseyshore has good take on it, see the quote below: ↓

The only thing that I can tell you for certain is that this was previously patched and those cracks have opened back up, which would seem to indicate continuing movement.

Is it possible that the foundation would have not fully settled after 50 years? While I know that the crack at the back of the house was fixed in 2012, I don't know when the crack at the front was repaired (the crack through the foundation wall, the balcony and the brick). The crack at the back was repaired by a professional according to the seller, but it looks like the crack at the front of the house was repaired by an amateur by the look of the repair.

I wonder how an engineer specialized in residential house foundation would evaluate the situation, without simply saying: there is not enough information, more expertise is required. This is what the building inspector did for this house. He was a good building inspector, but they almost all write that additional expertise are required, or that he could not access X and Y components. Engineers need data to evaluate, but in this situation, there are no more information than what we have here:
- There is no geotechnical drilling data available
- There is no concrete resistance information.
- I don't have a lot of history of the cracks.

 

[jerseyshore]

Don't feel too bad because that's 90% of the jobs we look at when evaluating existing foundations. There's usually not much info. We go based on what we see, our past experiences, and the dreaded engineering judgement.

That's why hiring someone is the most common recommendation on here because getting an engineer that knows the area can help fill in a lot of those missing data points. Local engineers may know the soil, adjacent properties, maybe even the original builder.

 

[bhiggins]

This is a serious crack if it is propagating through deep concrete walls. The cracks are symmetric and are located at the geometric center of the foundation. The foundation may be settling parallel with the observed cracks. The soils can be heaving if you are in an area with expansive clays. Like the others have said, I highly recommend hiring a local competent engineer to evaluate the foundation. Someone needs to go measure floor elevations to decipher the pattern of settlement and determine a root cause.