Retaining wall failing 1

[minnesippi]

New here - not sure if I’m in the right area or not but need assistance please.
Have retaining wall on residential property. “2 blocks high” at one end, 9 ft high at the other - curves around corner of house – double deep in one area (on a slope). I do not believe drainage was done properly. There are no “weep holes” and there is not an area below that allows water to exit from behind the wall. There is a culvert below the ground that it might be tied into. Retaining wall is separating in two areas with gaps of 5 to 6 inches between upper and lower block. Cap blocks are disintegrating as well.
Due to drainage and wall failure, corner of house is "dropping" and creating cracks in walls and ceiling inside the home as well as the cinder block in two different areas outside.
There is no record of a permit from the city (required) and the company will not reply to my emails to even a general inquiry about the wall or even the manufacturer of the block. Former home owner had it built, and rebuilt at least one time. Wall is 12+ years old.
Wondering if contractor would be responsible being a permit wasn’t pulled for the damage that is being done to the house as well as rebuilding the wall properly. I live in MN.
Appreciate any help provided – or a direction I can go. $20,000+ for a new wall, my insurance won’t even look at it unless we dig the wall out and expose the corner of the house that is sinking.
Please help! Thank you in advance

 

[msquared48]

I agree with Hokie here. Use the pin pile as that is the best option, short and long run. However, you will still need a geotech to tell you the allowable value for the pin pile to use, and a structural engineer to get it past your local jurisdiction.

Considering what happened, the jurisdiction should be willing to work with you.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[cvg]

since you are in Minnesota, you must have a basement. Based on the photos and my pitiful attempt to figure out the layout and elevation of your site, it appears that the basement is cut into the side of a hill. Top of retaining wall is approximately level with your first floor? And where you are standing in the photos would be just about basement floor level? so if my assumption is correct, the house is not built on fill. The fill was placed against the front of the basement wall and retained to create a flat yard? If so, then could the retaining wall failure and the basement wall failure be un-related? However, I do see a downspout at the corner of the house. I do not see that pipe exiting over the side of your retaining wall. It appears it is draining right below your cracked section and right behind the part of the wall where it is failing. Almost certainly, that is a contributing factor.

 

[concretemasonry]

After looking at the photos provided, the installation should have been engineered instead of arbitrarily breaking the wall into different portions and just applying some information based on low "gravity walls" to make it look good at first. The drainage systems are obviously poor and not maintained.

Looking at the geography and trees surrounding the home (and living in the area for many years), it appears that as earlier posters commented on, are correct that this was a hillside site the was excavated for the foundation and basement and later filled. The wall construction followed later without any real engineering and using segments to partially get around some unenforced permitting requirements and neglecting the upper wall segment loads that allowed the settlement/distortion and possible loss of support for the home foundation.

I was involved in the early use of segmental retaining walls and later, during international travels (Europe, China, Australia, South America, etc.) and saw some amazing engineered walls in harbors or along a freeway with set-back walls and individual walls over 40' high. All of the major product developers/ franchisers/licensors have good engineering support for all engineers to consult with, but because of the rash of firms being able to produce similar units there have been many poor examples due to miss-use or poor quality control. I was also a part of a durability study on the problem of the caps that involved many DOTs, etc to arrive at a standard, which hopefully has been corrects by ASTM product and testing standards. One of the big problems was the acceptance of silicone to provide an attachment of the solid cap block to the wall.

In our area, the counties and municipalities have standard construction and use standards for use in the field regarding the routine use of low gravity gravity walls (under 5' high) for road realignment/widening, sidewalk construction, but rely on the approved suppliers to assist in the engineering.

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[Ron]

Agree with other comments. The two issues are not necessarily related, although there is certainly evidence that points to a relationship.

The segmental block wall quite possibly does not have filter fabric or a drainage layer behind it. It appears, as Mike noted, that the foundation for the wall has failed at least in an isolated location. Considering the gaps there is likelihood of some lateral material drift, which reduces or changes the density of the material under the house, thus might be a contributor to the observed settlement.

Agree that you need to fix the house foundation. Pin piles or helical anchors would likely be the better options. Both can be installed with relatively portable equipment.

The wall can be disassembled and rebuilt on a proper foundation. You have some obvious freeze-thaw damage to some of the blocks. Be sure to consider that when you re-purchase.

 

[minnesippi]

Thank you all.
cvg - you are somewhat correct. The house (duplex)is built into a hill, but to the best of my knowledge, it was not filled. The house to the west was excavated to be flat, and has a cinder block retaining wall from the end of my wall to the back of the property line - all others around are level with our back yard - and my street (front yard) is level with the street and neighbors to the west. Swampland to the north, neighbors retaining wall to the east. So there is a defined hill that the house was built into - not saying there wasn't some sort of fill being it is "3M swampland" in the front. Correct - drain pipe leads directly into the wall with no exterior exit - but possible tie into culvert draining into swamp.
House built in 1976 - by an electrician who cut every corner he could from what we have see thus far. Yes - thank you former in-laws so much for the money pit. Now I know why they did a "by owner" sale. Ugh...what a headache. So if I understand correctly, I need to contact a geotech and an engineer to have them come take a look-see. And they should be able to help determine what is causing what? Recommend anyone in MN - twincities area?

 

[cvg]

just thinking outside the box here:

since the basement wall was originally built at grade and then later soil was placed against it and retained with a wall, additional load was placed on the concrete basement wall. that wall may or may not have been designed to handle the additional soil load. Could that additional loading be causing additional stress on the basement wall which is then transferred to the structure above? - thus causing the cracking that is being atributed to foundation settlement?... Will the insurance policy cover that and can you prove it?

 

[bridgebuster]

The only party you can sue is the seller. Since you're no longer related to them, don't feel bad about it. You may have an uphill battle assuming you were given the opportunity to inspect the property. If no problem was visible but the owner knew of a problem you could have a case for negligence. On the other hand - and granted, laws vary among the states - "As Is" doesn't necessarily mean a house can be sold "As Is." Ugly paint & carperting is one thing but a structural problem or non-functioning heating, etc is different.

Also, if you could identify the manufacturer of the wall, a technical rep might be willing to give you some free advice on a remedy. No one likes to see their product get a bad rap.

 

[csd72]

To be frank,

I would recommend you get a structural/civil engineer involved that has experience at underpinning/subsidence surveys. It is like sherlock holmes detective stuff sometimes and it is often the minute clues that you find on site that tell the true story.

Compared to a proper survey, the comments on this site are mere educated guesses.

Not sure that you could sue the previous owners as houses are usually sold 'as seen' but we are not really the people to ask. From my experience a non legal solution usual has a more predictable outcome (can you afford for 50k plus of legal fees if your case fails?)

Focus on ensuring that the house is adequately supported first as this is the most expensive structure.

Not sure where the 20k sum comes from but I imagine that the damaged parts of the wall could be rebuilt and the capping stones replaced for considerably less.

Dont stress too much about the cracks, I have seen much worse, and most cracks are really an aesthetic issue rather than a structural problem in themselves.

 

[chicopee]

I would contact Holme on Homes which is a TV show and find out if he could help restore the retaining wall. I don't believe he charges since the repairs would be televised nationwide.

 

[minnesippi]

Chicopee - I've looked into that - he only does work in Canada Would be great though! He would have a hay day with this house! It would have to be a mini-series, not just one episode! LOL!

Again, thank you everyone. I was just at a trade show in Vegas for ICPI and tossed around many conversations. Heard a lot of the same things there as I did here...which didn't surprise me.

I will keep you updated.

City got back to me - they have no record of any permits being pulled for this property except for the roof we replaced last summer. That didn't make me very happy. She even had the IT Dept go through archives...nothing. Wish I would have known these things 8 years ago. Hind sight...