Alchatek Blog

An old farmhouse with a wrap-around porch in Lake Orion, Michigan, presented a unique challenge. Beneath the porch lay an old cellar, initially used for coal storage but now serving only as a conduit for a well line into the residence. The primary concern was the inward buckling of the cellar walls, which posed a significant safety hazard. Many contractors suggested demolishing the porch and excavating the cellar, a solution that would have incurred substantial costs for both demolition and reconstruction.

Initial Assessment

Suburban Basement was engaged to address this issue. Upon evaluation, the team identified a more cost-effective and less invasive solution. The cellar, measuring 12 feet in length, 5 feet in height, and 5 feet in width, could be filled with foam to mitigate the risk of further wall collapse. This approach would spare the property owner the expensive and disruptive process of demolition and reconstruction.

Proposed Solution

The team proposed filling the cellar with Alchatek’s AP Lift 430 foam. This material was chosen for its extensive expansion rate, superior compressive strength, and lower application temperatures. These properties allowed for quicker application intervals while maintaining optimal temperatures between applications and minimizing ignition risks.

Procedures

1. Encapsulated the well line with sonotubes elevated above the cellar floor, ensuring future accessibility.
2. Installed OSB sheathing to define foam boundaries and prevent overflow.
3. Applied AP Lift 430 in layers, allowing cooling intervals between applications to optimize expansion and stability.
4. Coordinated with masons to prepare for CMU block installation at the containment boundary, ensuring seamless alignment with the existing foundation.

Results

The foam-filling solution successfully stabilized the cellar walls, eliminating the collapse risk while preserving functionality. Compared to traditional approaches, this method saved the client approximately $25,000 and maintained the home’s historic features. Completed in just five days, the project significantly outpaced conventional methods. Homeowners were highly satisfied with the noninvasive approach, cost savings, and seamless integration with their property’s historic character, demonstrating the effectiveness of innovative techniques in addressing complex structural challenges in historic properties.

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Suburban Basement was contracted to address a multifaceted water intrusion issue on a Rochester Hills, Michigan property. The basement had water ingress from both the furnace ductwork and the foundation. The ductwork, extending through the foundation wall into a garage-adjacent wall cavity, had sections below grade behind a garage curb. The root of the problem was water pooling under the back curb, caused by settled garage slabs from the main vehicle entrance.

Initial Assessment

The project was divided into two phases: first, addressing the leaking foundation and furnace ductwork, and second, void filling and concrete leveling of the garage floor and curb. The complexity arose from the undermined garage slabs and the need to prevent water intrusion while ensuring the safety of the furnace ductwork.

Proposed Solution

For the initial water intrusion, Suburban Basement proposed using Alchatek’s Spetec PUR Highfoamer for curtain grouting, given the limited accessibility and its fast reaction time. For the concrete leveling and void filling, AP Lift 430 was selected due to its expansion rate, soil stabilization capabilities, water displacement properties, and quick curing time for vehicle traffic.

Procedures

1. Applied curtain grout to the positive side of the wall to stop water intrusion and encapsulate the dual wall furnace ductwork
2. Commenced void filling and leveling at the garage curb, progressing toward the main vehicle entrance
3. Filled all voids beneath the garage curb and leveled the concrete across all areas of concern
4. Conducted water tests to ensure all leaks were addressed before proceeding to phase two
5. Performed void filling and concrete leveling, displacing significant amounts of water near the main vehicle entrance

Results

The project was completed successfully in two phases, with the curtain grouting finished within hours and the void filling and concrete leveling taking approximately half a day. All leaks were effectively stopped, and the concrete was successfully leveled. The homeowner expressed high satisfaction, notably as previous repair attempts had failed. Suburban Basement’s solution not only resolved the immediate water intrusion problems but also extended the lifespan of the garage concrete and driveway, providing a comprehensive fix to a complex issue.

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The owner of a gas manufacturing facility contacted a Georgia-based contractor regarding significant floor settlement issues, with a warehouse slab dropping approximately 3-4 inches. The settlement made issues for the forklift traversing in and out of the warehouse and posed a risk to the workers.

Initial Assessment

Upon arrival at the site, the team conducted a thorough investigation. Using a probe, voids were identified beneath the slab, with the probe sinking up to 2 feet in some areas. A Dynamic Cone Penetrometer test revealed large voids 2-4 feet below the slab.  Poor drainage was evident, with improper crowning causing water to flow towards the building instead of away from it. Interestingly, a layer of unusually hard clay was noticed outside the building, suggesting possible prior remediation attempts.

Proposed Solution

AP Lift 430 was chosen for this project, providing an excellent injectable polyurethane grout solution. With its impressive 22x expansion capability and 7,200 psf compressive strength, it’s ideal for warehouse slabs that support heavy equipment. The grout’s hydrophobic properties ensure long-term stability by blocking water infiltration that could otherwise lead to void formation.

Procedures

1. Deep Injection (Void Fill)

• 32 injection points were established in a grid pattern (16 on each side) at 4 ft apart.
• At each point, the team injected 15-20 pounds of material at about 5 feet depth.
• A slight lift (approximately 1/16 inch) during this phase indicated successful void filling.

2. Slab Lifting

• Additional holes were drilled next to the wall, 3 feet from the wall, and 9 feet from the wall (6 feet from the first row).
• Injection began from the holes nearest to the wall and moved outward.
• Multiple passes were made, with some areas requiring 3-4 injections.
• Gradual lifting was employed to prevent slab cracking.
• Dial indicators were used to ensure even lifting across the warehouse floor.

Results

The project successfully stabilized the warehouse floor and restored it to its proper level. Effective void-filling addressed the underlying instability, providing a solid foundation for the slab. Success was evident in the restored functionality of the warehouse space and the elimination of safety hazards posed by the uneven floor. The property manager was pleased with the work and requested additional slab lifting services for their other facilities.

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The owners of a college apartment complex in Georgia reached out to a local engineering firm after discovering a large void underneath the northwest end of the building. The issue was caused by stormwater collecting and flowing beneath the building's foundation. Over time, the foundation became exposed and now the grade has lowered by a foot from the original design.

Site Investigation and Initial Attempts

A dynamic cone penetrometer test revealed the soil was fragile, with two to three blow counts for the tested areas. Underpinning piles had been installed by the previous owner, but did not did not adequately stabilize the building's foundation. The shifting foundations caused the ceiling and wall in one of the top-level rooms to begin to crack and showed early signs of separation.

Proposed Solution

The engineering team recommended using injectable polyurethane grout. AP Lift 430 was selected for the job because of its high expansion of 22x and compressive strength of 7,200 psf. This polymer is also hydrophobic, which prevents water from causing further erosion of the void.

Implementation

1. Rod Placement: Injection rods were inserted horizontally into the void’s back, spaced 4 feet apart.
2. Foam Injection: Foam was injected through the rods until emerging from the exposed void area. This step ensured that the foam reached the farthest areas of the cavity.
3. Free-Shooting: The remaining exposed void was filled by direct foam application, ensuring comprehensive coverage.

Results and Conclusion

The end result was 658 gallons of expanded AP Lift 430 injected underneath the void. The polyurethane injection, combined with regrading work done in collaboration with a local engineering firm, successfully solved the issue and prevented further void formation underneath the student housing.

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A broadband provider in Alpharetta, Georgia, contacted a local leak seal contractor after discovering water infiltration through a crawl space wall during heavy rainstorms. Over time, cracks had developed, allowing not only water but also sediment to enter, creating substantial voids outside the fissures upon inspection. Given the sensitivity and high value of the equipment housed within the facility, eliminating all potential leaks in the crawl space became a top priority.

Powerful Polymers

The technicians chose Alchatek’s Spetec PUR HighFoamer to address this leak. This highly expansive polyurethane grout creates a robust, waterproof barrier, effectively sealing a wide variety of leaks without extensive excavation. Spetec PUR HighFoamer’s remarkable expansion capacity (40x-50x) ensures comprehensive coverage and a tight seal, making it ideal for projects requiring minimal downtime. Its NSF 61 certification guarantees safety for potable water applications, positioning this product as a versatile and cost-effective choice for leak sealing projects across various industries.

Painless Procedures

The repair process consisted of three efficient steps. First, the crew drilled through the concrete wall, installing zerk fittings into each hole for subsequent injections. Next, they used an electric airless sprayer to inject water into each fitting, ensuring proper activation of the foam. Finally, they injected Spetec PUR HighFoamer through these fittings. This created a curtain wall of polyurethane foam that effectively sealed the cracks, prevented further water ingress, and filled voids in the soil substrate.

Rapid Results

Within 24 hours, the technicians successfully sealed all leaks in the underlying crawl space. This injection process was completed in a fraction of the time required for a full membrane replacement. Months after the repair, following several heavy rainstorms, the facility manager confirmed that the crawl space has remained completely dry, with no recurrence of leaks.

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