Small team delivers large scale waterproofing for hospitals

New Modern Hospital Outpatient Surgery Center

Danrae Group began decades ago as a family business, and we’ve grown to become an industry leader in comprehensive waterproofing solutions for commercial, strata, civil and government projects.

While we have a small team of waterproofers and trades specialists, we’re equipped for large-scale waterproofing, diagnostic, solution design and remediation… thanks to exceptional expertise and capability.

Our clients include several Sydney hospitals. Here’s how we provide first-class and large-scale roof waterproofing for clients including RPA, Concord, Campbelltown, Camden, Bowral, Marrickville, St Vincent’s and Westmead Hospitals.

Truck crane lifting an equipment to the rooftop

Expertise in large-scale solutions

Last year we completed a major project for Westmead Hospital, laying around 5,500m2 of waterproofing membrane. It involved solution design, waterproofing, remediation… and expert coordination.

To prepare the site, lay our choice of Sika Sarnafill and G410 20L PVC sheet membranes and complete full remediation, we appointed a head supervisor to remain on-site permanently and coordinate the teams.

Our skilled team completed all detailed work including hand welding, the installation of walkway pads and liquid membrane application.

We also organised cranes to haul materials onto and off the roof, an electrician to install temporary power, fire safety technicians to relocate fire sprinklers and height safety experts to secure the location and install railings. Our team is already height safety certified, so we didn’t require any additional training.

We completed the project smoothly and within the timeframe – thanks to our expert team and expert coordination.

Plenty of stones

Capability for full project management

At Danrae Group, we oversee every project from concept to completion – no matter what we encounter. At St Vincent’s Hospital Clinic, we met several challenges that we needed to address as part of our roof waterproofing and remediation solution.

The hospital had water seeping into the MRI theatre, which is home to highly specialised technology. We had to fix the issue as quickly as possible to protect the expensive equipment, and ensure there was minimal disruption to patients and staff.

In addition to the noise and time constraints, we discovered the roof was covered with a rock garden containing stones up to 300mm in diameter – and a restricted area with exhaust pipes that could potentially release toxic gases from the MRI equipment. We organised high-reach cranes to remove the stones, liaised with air conditioning installers to remove rooftop units (and reinstall afterwards) and outfitted our team with breathing apparatus in order to complete the work.

With the site clear, we laid a light-grey long-lasting PVC membrane, specifically chosen to help with temperature control inside the hospital. Our final step was to triple test the quality of our waterproofing with internal, brand representative and independent testers.

Rooftop view of a building

Processes for long-term waterproofing solutions

At Danrae Group, we have proven processes to ensure we deliver permanent waterproofing solutions.

In 2019, we completed a 2000m2 roof refurbishment at Campbelltown Hospital for South Western Sydney Local Health District. We removed the existing membrane, which had deteriorated causing leakage into wards, craned materials onto the roof and we glue fixed and heat welded the waterproofing membrane using robotic welders. We then installed walkway pads for foot traffic to ensure the roof membrane would remain clean and in good condition over the long term.

We chose a Sika Sarnafil system, which is ideal for flat roofs that need to withstand weather extremes… and, which if looked after, will last over 20 years.

We also designed a preventative maintenance plan to clean the membrane and catch any potential issues immediately. It’s the best way to preserve the structural integrity of the waterproofing membrane, to protect your warranty – and to preserve your property.

A group picture outside the office

Our large-scale waterproofing solutions

Danrae Group’s small team goes to great lengths to deliver large-scale waterproofing for hospitals, high-rise apartments, government buildings and even botanic gardens.

And we have the expertise, capability and processes to ensure our waterproofing is high quality, industry compliant, efficient… and always permanent.

If you need large-scale roof waterproofing from an expert and dedicated team, please contact us.

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