CASE STUDY
POOL SURROUNDS - WELLINGTON POINT QLD
PROJECT OVERVIEW
A detailed survey of the site revealed significant subsidence and settlement issues on the eastern pathway access to the rear of the property. The easternmost edge had subsided by 40mm, causing the path to the exterior wall joint to open with a nominal width of 35mm. Additionally, the lateral pathway joints were misaligned, and the path exhibited incorrect longitudinal fall (40mm over 7.0 lineal meters). Further investigation uncovered separation and subsidence of the inground pool apron slab from the coping by -10mm to -70mm over approximately 15 lineal meters.
SCOPE OF WORK
The scope of work involved utilising a Zip Level Pro 2000 precision altimeter to measure all heights accurately. The primary focus was on addressing the subsidence issues in the eastern pathway, the misalignment of lateral joints, and correcting the longitudinal slope of the pathway. Additionally, the solution aimed to raise the pool apron back to -10mm of the pool coping and implement suitable sealants to address joint concerns.
PROPOSED SOLUTION
Slab Jack Industries proposed a solution involving the use of Structural Polyurethane Lifting Foam (chemical underpinning) for the raising and re-levelling of problematic areas. The selection of this solution was based on its relative cost-effectiveness, non-destructive installation techniques, and minimal asset downtime of less than 8 hours.
Through careful analysis and the clients communicated requirements, the criteria for success was to be measured against the following benchmarks;
Closing the house to path joint to – 10mm
Lifting the eastern edge of path way + 35mm to ensure slight fall from house
Achieving re-alignment of lateral path way joints
Correcting longitudinal slope on path way
Raising pool apron back to -10mm of pool coping
Installing suitable sealants to joints as required
OUTCOME
Upon installation and application of Structural Polyurethane Lifting Foam, all success criteria were not only met but exceeded expectations. The house-to-path joint was successfully closed to -10mm, the eastern edge of the pathway was lifted by +35mm to ensure a slight fall from the house, lateral pathway joints were realigned, longitudinal slope correction was achieved, and the pool apron was raised back to -10mm of the pool coping. Furthermore, suitable sealants were installed to address joint requirements, showcasing the effectiveness of the proposed solution.