Penetron Liquid Sealer Keeps Moisture and Water out of Olympic Pool Concrete Structure

Penetron Liquid Sealer Keeps Moisture and Water out of Olympic Pool Concrete Structure

St Joseph’s College in Hunters Hill (NSW), Australia, inaugurated the school’s new Olympic class 50m swimming pool and two-story pool house to the campus at the commencement of the 2023 school year in January. Penetron crystalline technology, a Penetron liquid sealer, was applied to provide a permanent waterproofing solution – to seal hairline cracks and protect concrete pool structures against water penetration.

Approximately 7.5 km (4.6 miles) northwest of Sydney’s Central Business District, Hunters Hill is a suburban community known as “the French Village,” thanks to its heritage of Frenchmen first settling the area, with grand homes, public buildings – and a beautiful sandstone boarding school for boys. The story of the school began in 1872, when four Marist Brothers arrived from France to open Australia’s first Roman Catholic boarding school.

St. Joseph’s College, Hunters Hill accepted its first students in 1881 when a steamer dropped 44 boys at the Fig Tree Wharf, which was a mere four-minute walk up the hill to the new school. Since then, the school has seen Hunter’s Hill grow from a bushranger refuge in the 1840s to a uranium refinery early in the 20th century, and now, to a beautiful tree-lined suburb. Today, St Joseph’s College is an independent Roman Catholic school and Australia’s largest boarding school for boys, with over 1,000 students and over 200 staff and teachers.

“In addition to a tradition of academic excellence, physical education plays a central role in the development of St Joseph’s College students,” explains Steve Hodkinson, General Manager of Penetron Australia. “To enhance this aspect of the school’s curriculum, the school recently decided to replace its existing outdoor pool originally built in 1957.”

More about the project

The St Joseph’s College Memorial Pool Redevelopment project to upgrade the school’s aging 50m swimming pool to an Olympic class facility began in 2020. The $30 million project included construction of an 8-lane, 51.5m pool ranging from 1.1m deep to 2.0m deep, which can be converted to a 25m outdoor recreation pool and FINA-standard water polo pool (with a dividing movable boom), a pool perimeter deck, a two-story building (to accommodate multipurpose areas, offices, storage rooms, and basement pool plant), and landscaping.

“A standard Olympic size swimming pool holds about 2.5 million liters (660,430 gallons) of water, which translates into 2,500 tons of weight. That creates an immense level of hydrostatic pressure on the pool’s concrete structure,” adds Steve Hodkinson. “Obviously, the sheer amount of pressure demanded an equally robust waterproofing solution to keep water and moisture out of the pool’s concrete structures and enhance durability.”

FDC Construction, the general contractor, asked Penetron Australia to provide a durable waterproofing solution for the outdoor, below-grade concrete pool structures. Penetron is a topical crystalline waterproofing material. Contractors mixed it into a layer of slurry. Then Firmstone Flooring, a specialist flooring company and Penetron-approved contractor, applied it over the concrete pool surfaces. This sealed the hairline cracks and protected concrete against water penetration. They also treated the pool’s construction joints and penetrations with Penecrete Mortar, a crystalline waterproofing repair grout, to complete the waterproofing system.

Penetron products used

Once applied to the prepared concrete surface, the proprietary chemicals in the Penetron slurry (and PENECRETE MORTAR) react in a catalytic reaction with the moisture in concrete to generate a non-soluble crystalline formation throughout the pores and capillary tracts of the concrete. This formation becomes an integral part of the concrete matrix during the service life of the concrete – to self-heal and seal micro-cracks, pores, and voids (up to 0.5 mm / 1/51″ wide) against the penetration of water from any direction.

“Even when topically applied, the crystalline growth generated by the Penetron application penetrates deep into the concrete structure and grows throughout the concrete matrix from the point of application. This protects the concrete from the enormous hydrostatic pressure of the pool water and will last for the service life of the structure,” concludes Steve Hodkinson. “It’s a permanent – and cost-effective – protection for the pool structure.”

About The Penetron Group

The Penetron Group is a leading manufacturer of specialty construction products for concrete waterproofing, concrete repairs, and floor preparation systems. The Group operates through a global network, offering support to the design and construction community through its regional offices, representatives, and distribution channels.

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