Case Studies

Thunder Bay Builders

Florida's premier sinkhole experts

In 1993, William McDonough founded Thunder Bay Builders (TBB) as a small residential and commercial remodeling business. Over the years, the company grew, serving customers in central western Florida. When the economic downturn destroyed the housing market, however, the company found new ways to stay afloat. Now, the company serves as one of only a handful of successful sinkhole remediation businesses in the state.

Matt O’Brien, president of TBB, has been with the business since 2007. “I had opened a furniture store in Stewart, Fla.,” O’Brien explains. “I became involved when TBB decided to start a new division. Sinkhole work was a revision for the company. Since the beginning of the division TBB has experienced growth year after year.”

O’Brien purchased the company in September 2013. He works with a team of 37 dedicated employees, including more than 25 in the field who take on the dangerous task of repairing sinkholes that threaten homes and communities. The crew operates from a main location in Spring Hill, Fla., which houses office space and a 5,000-square foot warehouse. TBB also has a satellite office in Largo, Fla. The team performs sinkhole remediation work in the area known as “Sinkhole Alley,” encompassing Citrus, Hernando, Pasco, Hillsborough and Pinellas counties along the state’s central Western Coast.

Dirty work

“Some jobs you are drilling and the yard next to you disappears,” O’Brien explains of his team’s projects. “You just have to wait until the ground stops dropping out. If it is disappearing at the surface, then sand and soil has been disappearing from the under the ground for some time, spreading the void upward to the surface. A homeowner may have been walking on nothing but grass.”

There is a dangerous aspect to the company’s work. O’Brien explains that once a hole forms, it will eat its way back until it stabilizes. “We have never lost anyone and I have never known of anyone in our industry who has fallen in and died,” he notes, “Though our vice president fell into a sinkhole while working for a different company. They had to dig him out. He was quite a bit younger, working on a project and standing on a drill rig that fell in the hole.”

Normally, homeowners see cracking and call an insurance company. Customers may not see a void or hole, but O’Brien says there are definitive signs. Engineers test the soil and if weak soil or a void is found, TBB comes in. To repair the sinkhole in the ground, the team pumps a concrete mixture called grout through casing to fill the void.

“Our projects range from 10 cubic yards to 800 cubic yards,” he continues. “Often, we’ll find a decent sized hole under a house. We bring our drill in, implanting a three-inch casing using a water drill so we can tell when we lose circulation. We leave the casing in the ground and pump grout, pulling the casing out of the ground until we get to grade. We have an engineer on-site all the time. Hernando County is best known for these sinkholes, though we see them throughout our service area. I have seen one that was 4 feet wide and so deep I could not see the bottom.”

Shifting focus

The sinkhole market has become increasingly difficult market in Florida over the last few years. In regions that have sinkholes, the only insurance that will cover these issues is the state-run Citizens Insurance. “They control the market and they have passed some legislation that makes it much more difficult for homeowners to file for claims and see them through,” O’Brien explains. “In a few years, we anticipate having to be ready to change course again to keep growing. Sinkhole work will diminish. We don’t do commercial work now. We would like to stay with residential contracting.”

While sinkhole repair has been the bread and butter of TBB’s business for several years now the team is getting back into residential construction. “We are just getting our feet wet,” Obrien notes. “We haven’t built anything yet, but we have brought on a person to run our homebuilding division. We have obtained proprietary plans from architects to get started.” The crew has just started building the first spec home that will hopefully segue into a larger market share in residential construction.

O’Brien estimates that 2014 will be the company’s biggest year yet. “By 2015 we’ll be looking to have the next division operational,” he explains. “We will concentrate on making that profitable. As sinkhole work declines we are confident homebuilding will go up.”

The company’s strong commitment to quality and safety will help the business remain stable throughout the transition. Whether filling sinkholes or building new homes, clients find Thunder Bay Builders a reliable, service-oriented contractor.

Published on: November 10, 2014

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