Peterson Geotechnical Group

11/19/2025

PGG was recently hired by a homeowner who was trying to sell her home. Prior to listing the home, they replaced the carpet in the master bedroom and found a crack in the floor slab. The realtor recommended that this homeowner consult with a "foundation specialist" and see if repairs were needed. A sales company that does foundation repairs visited the home and recommended a $30,000 repair. The homeowner was floored and very concerned because they felt they needed to disclose this report to potential buyers. My office visited the home and noted that it was a 30 year old home, there were zero drywall cracks, the levelness of the floor was within tolerances for new homes (around 0.6 inches), and the crack in the concrete floor slab was a normal shrinkage crack (around 1/8 inch wide). The home did not need any repair. We looked into this "foundation specialist" and found that they are nothing more than a sales company. They have zero engineers in their Arizona office and unfortunately, they push for these repairs all the time. If you believe you have issues, contact an engineering firm. Do not agree to foundation repairs from a foundation repair contractor without consulting an engineer.

12/16/2020

One tool that is used to evaluate whether soil movement has occurred is a floor level survey. With this tool, we are able to measure the current elevation differential across the home. I use the word "current" because this tool is only a snap shot in time. It measures the current elevation level but it is impossible to use that tool and know what the differential was at the time of construction. Foundation/floor slabs are not built perfectly level. In fact, studies show that they can be between 0.5 and over an inch out of level at the time of construction. I recently worked on a home that was poured 1.6 inches out of level and it was new. The differential was noticed immediately by the contractor and we helped them to address it.

Although this floor level survey is a tool, it MUST be used in conjunction with crack patterns inside the home. In addition, it is often wise to do repeated floor level surveys over time in order to understand how much the home is actually moving and if (and what) repairs truly are necessary.

I have found that some repair contractors and engineers will use the floor level survey and make conclusions about the current differential by assuming the slab was poured perfectly level at the time of construction. That is completely inappropriate. In fact, I was called yesterday by a gentleman that had received a forensic report by a contractor which was stamped by an engineer. The contractor had performed a floor level survey and determined that the home was 1.3 inches out of level. The home was about 6 years old. This is not a significant differential for a home of such an age. In addition, this contractor and their engineer even concluded that the foundation had "failed" because the slab had an angular distortion of 1 inch over 24 feet. This is a reckless conclusion because 1) they assumed that the slab was perfectly level at the time of construction, 2) a foundation does not fail even if he had that kind of differential, and 3) they proceeded to give very expensive repair recommendations based on this conclusion.

I looked at the performance of the home and I only observed one drywall crack that was possibly soils related. I concluded that the home was performing very well from a geotechnical standpoint and was surprised that this contractor and their engineer would come to such a ridiculous conclusion. The homeowner was very concerned and felt this contractor had used fear tactics to try and push expensive and unnecessary repairs on them.

This is just another reason to use an engineering firm to evaluate such problems that is not trying to sell you an expensive repair. It is also important to select a company that has engineers on staff or consults with engineers that understand basic construction and when repairs are even required. A good engineering company will never use fear tactics and conclude that a foundation is failing based on reckless conclusions and data.

11/04/2020

PGG has been involved with a school that has experienced significant soil movement and damage. We worked with the school district during litigation and were able to determine that there were numerous design and construction deficiencies. We also worked with a local structural engineering firm to evaluate the problem and to design a repair. The school has now selected a contractor to make the repairs and we are working with them to finalize the design and oversee the repairs.

08/19/2020

Peterson Geotechnical Group recently consulted with a homeowner to evaluate some damage to her home. The homeowner had already spoken to 3 different specialty foundation repair contractors. One of the repair contractors told her that the soil movement was so severe, that her roof could collapse unless she did something immediately. Another repair contractor tried to tell her that an extensive foundation stabilization repair was necessary. The third repair contractor told her that there was some minor movement but she should contact an independent geotechnical engineer.

We evaluated the home and there was some minor soil movement in the kitchen. A floor level survey was performed but the floor was relatively flat in that area. Drainage was poor right outside the kitchen area so we recommended fixing the drainage and monitoring the home. Drainage is the most common catalyst of soil movement. If you address the drainage, the problem most often goes away.

The home is 25 years old and the cracking is minor so there was zero need to spend thousands of dollars to pier and stabilize the home. And there is ZERO evidence the roof was going to collapse.

In this instance, the first repair contractor was utterly reckless. The second repair contractor was also reckless because they tried to push for a major repair to address a minor issue. The third repair contractor was the most honest and gave the best advice to the homeowner. There really are some good repair contractors out there that give good advice like this on a regular basis. In fact, we currently work with about 5 different ones and most do great work. There are just a few of them that push ridiculous repairs, use pressure sales, and/or misdiagnose the problem.

The best thing a homeowner can do is to get an independent assessment from an engineer or engineering firm not associated with the repair contractor. The assessment may be a little more money, but an independent engineer is not trying to sell you a commissioned repair. Good engineer consultants will educate you, explain the problem, and the give you options for a solution. In addition, I find that they will nearly ALWAYS save you money because they do not push for unnecessary repairs. In the instance discussed above, had she not consulted with us, she may have been convinced by one of the first two contractors that a $20,000 to $30,000 repair was necessary. It was not.

03/09/2020

PGG was recently hired by a homeowner to look at soil movement and damage to a home due to a water leak. The water leak occurred outside the home and ran for a few days. Water leaks are common triggering mechanisms of soil movement. In this case, the leak was adjacent to the rear of the home, which resulted in water migrating into the foundation bearing soils.

After evaluating the pattern of cracking, the floor level survey results, and the location of the water leak, it was very clear that the water loss had triggered clayey soils that expanded and caused the foundation to rise. The movement was not extreme and was concentrated along the rear of the home. The best remedy is to fix the water leak, give the soil time to dry out, and then monitor the home to see if additional movement occurs over time.

Found out that prior to hiring PGG, the homeowner had hired a foundation repair contractor to evaluate the damage. The foundation repair contractor also did an "engineering evaluation" and concluded the foundation had settled. They then tried to sell the homeowner $55,000 in foundation stabilization repairs. In essence, they wanted to install piers on the foundation to lift the foundation to the same elevation as the high area. I think they missed the fact that the high area was next to the water leak and was where the damage was located. It was an expansive soil issue and NOT a settlement issue. Completely inappropriate repair by a contractor that is either untrained in soil related issues, or is just trying to sell an expensive repair. Furthermore, their proposed repair would have done more damage than good to the home. Can't believe how often we find a certain repair contractor in town selling repairs that are completely inappropriate.

02/14/2020

Once again I was called by a homeowner that had hired a repair contractor to look at drywall cracks in their home. This repair contractor had done an "engineering evaluation" of the home and recommended extensive repairs (over $40,000). The problem is that the contractor completely misdiagnosed the problem and was recommending the wrong repair. Getting really tired of repair contractors trying to sell repairs that are completely unnecessary or the wrong repair. And as most of you know, I am not a repair contractor. I am an engineer that diagnoses these kinds of problems and provides repairs. This is the same repair contractor that I have run into on multiple occasions and seems to get it wrong on a regular basis.

12/16/2019

Working on a two story apartment complex that is experiencing significant settlement. Performed soil borings and found the building was built on undocumented fill soil (that was not compacted). The building has settled about 3 inches.

09/13/2019

My office frequently gets hired to visit homes and evaluate engineered repairs being recommended by specialty repair contractors. The repairs typically address some type of perceived soil movement and damage to the home. I am regularly shocked at the repair recommendations some of these contractors will offer. I have literally seen homes with normal drywall cracks but yet, the specialty contractor is recommending $30k or more in foundation stabilization and repairs. My advise to anyone that gets such a quote from a repair contractor is to get a second opinion.

07/31/2013

Check out the current issue of Attorney at Law Magazine featuring an article written by Curt Peterson "What are Earth Fissures?"
http://digitaleditions.walsworthprintgroup.com/publication/?i=167391&p=28

What Are Earth Fissures? By Curt R. Peterson, P.E. Curt Peterson is the founding engineer of Peterson Geotechnical Group, a forensic geotechnical engineering consulting rm. He holds a bachelor’s and master’s degree in civil and geotechnical engineering and has observed thousands of structures throug...

11/02/2012

We are happy to share an article written by Curt Peterson and published in Attorney at Law Magazine.

Geotechnical Engineering Why is my building settling and who is responsible? By Curt R. Peterson, P.E. R ecently, I received a call from the owner of an apartment complex in Arizona. The owner was concerned because one of the 5 year old apartment buildings had settled approximately 4-inches. The set...

10/15/2012

Homeowners: Be aware how to stop foundation deterioration

10/12/2012

There are areas in the arid southwest where salts are found in the soil. Some of these salts are water soluble and can migrate into concrete foundations, flatwork, and masonry fences and cause scaling/flaking of the concrete surface.