What happens after you notice the cracks?

In Residential Blog Posts by John Topa


Knowing the early sinkhole warning signs around your property can save you thousands in foundation repair costs down the road.  The sooner you can identify your potential foundation problems, the easier it is to fix them. Sinkholes can appear to have opened overnight, but the majority of them evolve over time, developing long before any surface evidence is detected. Areas where there is a lot of underground rock and clay soil are ideal for sinkholes. A common misunderstanding is that a sinkhole is an actual hole in the rock. But in reality, the sinkhole is what we see on the ground surface because of the hole in the rock below. If you are experiencing a number of these signs, here is what you should know and what to do.


 Houses settle over time, and a little unevenness isn’t caused for panic.  At the same time, you’ll want to be alert to these warning signs that more dramatic changes are taking place:

•      A door begins to jam or fails to latch

•      Cracks appear in walls, especially over doorways, windows or where walls meet ceilings.

•      Cracks open in vinyl or ceramic tile over a concrete floor

•      Windows that used to open and close easily suddenly begin to stick or won’t close completely

•      Cracks in interior joint areas

•      Uneven kitchen cabinets and drawers

•      Slanted floors

•      Water leaks or flooding when it rains

•      Stairs begin to slope

•      Nails begin to pop

•      Displaced moldings

•      Wet crawl space

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Ultimately, there are many different methods geotechnical firms use to test for sinkholes.  Our team is extremely familiar for all the different means used to test for sinkholes and have handled cases involving all of them so we can be relied on to be your trusted ally to ensure you peace of mind.

Standard Penetration Testing (“SPT”) – involves hammering and drilling a boring into the ground and actually sampling the earth below the drill. The strength of the soil strata are calculated and measured using “N” values. These “N” values are essentially attempt to measure the strength of soil by measuring the number of times a known force is utilized to force its way through unknown soils. It is often considered the most reliable and accurate manor of testing because it is considered “ground trothing” the actual soils and rock formations beneath a residence. The sinkhole attorneys of Hackworth Law have often compared SPT borings to a doctor performing an exploratory surgery after identifying something on an X-ray or MRI. Many firms are moving to automatic SPT rigs, which eliminate the potential for human error in pulling the cad head hammer by hand. It is important to confirm automatic SPT drilling takes into account the proper mathematic conversion to the cad head system. Unfortunately, it is the most destructive, time consuming and expensive of the forms of testing for sinkholes. Often times, many insurance companies will only authorize their geotechnical firms to conduct three (3) test borings.

Geophysical testing (like ground penetrating radar, multichannel analysis of sound waves ,etc.) – generally used to identify locations to conduct SPT drilling. This form of testing does not actually take physical samples or actually penetrate the ground. Working off of our previous analogy concerning X-rays or MRIs, geophysical testing is essentially the X-ray or MRI, that is confirmed by SPT testing.

Floor Elevation Survey – utilizes different measuring tools to measure relative changes in the floor elevation through a residence. This is extremely effective at identifying alleged movement of the floor slab between initial testing by the carrier to Insured’s later testing. Generally, slabs aside from the living slab are sloped away from the living slab to facilitate drainage in areas such as porches and garages. Often times, insurance companies will argue the floor slab was laid improperly, but they often run into issues as they have little proof concerning same.

Cone Penetrometer Test (“CPT”) – identifies the strength and/or density of surface soils without the time, expense and destructive nature of SPT borings. This is extremely critical in cases where residences have poorly embedded foundations because loose surface soils create conditions and damage mimicking sinkhole activity. CPT testing provides more raw data than SPT testing, but does not collect actual samples. This prevents this form of testing from enjoying the assurance of ground trothing that SPT borings offer.

Test Pits – measure the thickness of the foundation and the depth of embedment of the foundation. The Florida Building Code requires certain thickness for residential foundations. Ultimately, it is necessary to check the specific year of the construction of your residence and the relevant building code at the time.

Hand Auger Borings “HA” – identifies the condition and characteristics of surface soils and detects buried debris. This is critical to determine whether surface soils are causing damage to structures that mimic sinkhole conditions. Again, this form of testing permits geotechnical engineers and geologists to actually physically examine the samples recovered. These borings are often very effective at identifying buried debris or roots which may be effecting a residence.

Publically Available Sources (like USDA, published soil maps, Florida Geologic Survey) – review of these sources is important to identify the soils at property and the characteristics of the specific soil types, height of the water table and confirmed sinkholes in the immediate area. Experts hired by insurance companies often attempt to explain that neighboring sinkholes are not an indication of sinkhole activity at a residence, but they are unable to provide any specific scientific support of same. Additionally, it is nearly impossible for them to guarantee that the confirmed sinkhole is not affecting the neighboring residence in anyway. Additionally, sinkholes are often found in clumps or packs, where similar subsurface conditions are occurring.

Dynamic Cone Penetrometer “DCP” – calculates “N” values by using a smaller, mobile probe is hammered into the ground similar to SPT. In many instances, DCP may provide more accurate testing as it eliminates the potential human error and subjective elements of SPT borings. Unfortunately, though, it does not provide actual samples of ground recovered during the testing.

The testing process can consist of many different tests but the core process is Test Boring. This method involves the engineering firm bringing either a truck mounted or trailer mounted drill rig to your property and drilling into your yard to determine the nature of your soil. Soil samples are taken every 5 ft., independently packaged and sent to the lab for analysis. From this data, the engineers get a good idea of your soil conditions. This is important information for them and you.

Once testing has been completed within 3-5 weeks your adjuster should notify you of the results of the engineers’ report and have a copy forwarded to you.

If the report indicates that your property does have sinkhole activity, the insurance will then go to work to come up with a solution and determine how to handle your claim. No two insurance companies will handle a claim or resolve the claim the same way. Needless to say, some are better than others.

If the report shows that there is no sinkhole activity but some other type of settlement issue they are not liable for such as clay issues, organic material, muck or general subsidence then you as the home owner are stuck with the problem because as Florida insurance stands the only foundation issue that is covered in your homeowner’s policy is for sinkhole damage.

If you do not agree with the engineer’s findings you have a few options that are available to you.

A.      Hire an attorney. Negotiating this type of claim on your own is difficult at best outright impossible at worst.

B.      Hire another engineering firm to come out and retest your property. This usually costs around $4,000-8,000 so you should have a good basis for doing this such as multiple sinkholes within a reasonable distance from your home. PLEASE NOTE!! You must exercise caution with this option as you will be liable for the cost of the testing whether sinkhole activity is confirmed or not. This means that even if you find out that there is sinkhole activity, you will have to pay for the testing until your insurance company either reimburses you or pays the engineers themselves. You can resolve the situation on your own.

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Helicon is the premier geotech construction company in Florida. Based out of Tampa, FL. we are a licensed general contractor leading the industry in full-service geotech construction work.

We are experts in pre-construction, soil and structural stabilization, & sinkhole repair. As the premier provider of geotech construction services throughout the state of Florida for nearly 15 years, Helicon prides itself on providing high quality service, for both insurance companies and private customers with handling all repairs and pre-construction work for both residential and commercial projects. We strive to exceed everyone’s expectations.

Helicon has successfully completed thousands of projects in the state of Florida with a focus on the Tampa Bay metropolitan area, including the surrounding counties of Hillsborough, Pinellas, Pasco, Hernando, Polk, Citrus and Marion counties. Our professional Helicon Teams are trained and equipped with the tools and expertise needed to execute a flawless and professional experience using the latest technology to repair or prevent for your particular project.

We invest in our teams ensuring they remain up to date on the latest industry technology and training. Our Office Teams will answer all your questions, provide professional service, give knowledgeable advice, and execute a project that will fully satisfy our customers.