Case Studies: Winston Salem, NC – WBFJ Radio Station Fixes their Sinking Sidewalk

Thursday, February 25th, 2016 By Jaimie Hooker


The sidewalk outside of the WBFJ radio station in Winston Salem, NC had been sinking for years. The middle of the sidewalk had settled so severely, large cracks had formed along the sidewalk. During extensive heavy rains, water would collect on top of the sinking areas of the sidewalk and seep through the cracks causing the basement to flood below. The radio station had put off getting the issue fixed because of the drastic expense and disruption of total concrete replacement. When a member of the radio station discovered the PolyRenewal process, Tar Heel Basement Systems was called immediately.


Upon finishing a full inspection of the problems the radio was experiencing after heavy rains, System Design Specialist, Matt Wagoner, created a flawless design that would remove the worry of water intrusion entering the basement and correct the sinking slab problem without disruption to the parking lot or slab.

Before the installation process could begin, the PolyRenewal team removed the old, failing caulk that was installed as a quick fix to keep the sidewalk from sinking and the entire area was swept clean. Once the sidewalk was cleaned and prepped for install dime-sized holes were drilled every four (4) feet along the sinking sidewalk. During this process, the PolyRenewal team could tell the exact measurement of void that would need to be filled. The fill soil had failed so severely there was a two (2) foot void underneath the slab that would need to be compressed and filled before raising the sinking sidewalk would be possible.

Now that the small, dime-sized holes had been drilled, PolyRenewal inspection ports were fastened in the holes to allow for the polyurethane foam to be installed correctly. The high-density, waterproof polyurethane foam is then patiently injected under the slab, compressing the soil to create a stable base. Once the fill soil has been compressed, the polyurethane foam raised the sinking sidewalk slab. As the sidewalk slowly began to rise, the large open crack also began to close, no longer becoming a trip hazard for those visiting the radio station.

Once the slab had become stabilized and raised, the dime-sized holes were then sealed and grouted to match the rest of the sidewalk. The now closed cracks were also sealed with the Nexus Pro waterproof caulk. The Nexus Pro caulk is resistant to weather, ultraviolet rays and ensures no water can seep through the closed crack. The sidewalk at the WBFJ radio station now has a welcoming stabilized and level sidewalk thanks to the PolyRenewal team at Tar Heel Basement Systems.

Project Summary

Installing Contractor: Tar Heel Basement Systems

System Design Specialist: Matt Wagoner

Products Installed: PolyRenewal

About the author
Jaimie Hooker is the Assistant Marketing Director at Tar Heel Basement Systems; authoring case studies, technical papers, creating and captioning photo albums and managing website content. She also oversees the organization of video testimonials, shows and events, Jaimie lives in the small town of Madison, NC with her husband, Paul, and 3 year old son, Franklin.