Harbour Royal Apartments – Aamsko’s Weathertightness Documentation & Diagnostic Process

Project: 88 Anzac Avenue, Auckland CBD
Client: Body Corporate 170878
Consultants: Aamsko (NZ Property Practice Ltd) and Zenith Facilities Services Ltd

At Harbour Royal Apartments—an eleven-storey residential complex in the heart of Auckland’s CBD—the passing of time had begun to reveal early weathertightness vulnerabilities. Built in 1995 under the Building Regulations Act 1992, the building featured a direct-fixed EIFS cladding system (Insulclad), which had reached the edge of its expected service life. Following initial investigations by KRT Building Consulting, the Body Corporate engaged Aamsko and Zenith Facilities to document the condition of the building envelope and perform a detailed diagnostic analysis of water ingress at apartments 10C and 11C.

Background & Initial Observations

KRT’s preliminary building inspection in late 2022 had noted that the external cladding and joinery had met their 15-year durability requirements under the Building Code but showed signs of aged repairs and deterioration. Cladding joints had been repeatedly patched with sealant—a short-term fix that had ultimately failed under long-term weather exposure. KRT identified a lack of critical components such as air barriers and wall underlays, raising concern about internal damage hidden behind the cladding. Their invasive inspection at apartment 10C revealed water damage related to weak horizontal joints, with leaks tracking through the EPS (expanded polystyrene) panels and into the wall structure. These findings set the stage for Aamsko’s more detailed investigation, which aimed to define not only where water was getting in, but how and why—and to establish a repair methodology that would be fit for purpose over the long term.

External Survey & Rope Access Inspection

Zenith Facilities conducted a rope-access survey of the entire external façade in March 2023. This identified widespread issues with cladding alignment, sealant failures, corrosion around panel joins, and poorly executed historic repairs. Most notably, the original design drawings showed that head flashings and parapet cap flashings had been specified—but never installed. This omission left critical areas of the building exposed to uncontrolled moisture entry. Misalignment at panel joints, rust bleeding through surface coatings, and deteriorated silicone joints were particularly evident on the north-west and southern elevations. Apartments 10C and 11C were flagged for detailed inspection due to repeated water ingress reported by the residents and building manager.

Invasive Inspections at Units 10C & 11C

On 15 May 2023, Zenith performed targeted invasive inspections in units 10C and 11C. Wall linings were removed to access internal steel framing and confirm the source and extent of moisture damage. Key findings included:

• Unit 11C Lounge (Northwest):
  • Water damage at the upper corner of the corbel ledge framing.
  • Flooding and rust in horizontal steel C-sections inside the EPS cladding.
  • Historic repair foam and staining showing long-term ingress patterns.
  • No damage to the slab-to-panel fixings, suggesting ingress was travelling behind the cladding and pooling within steel framing channels.
• Unit 10C Second Bedroom (Northeast):
  • Water damage and historic staining around the concrete slab beam.
  • Moisture trails suggested water was running down from the floor level above (unit 11C), through voids between the slab and panel frame.

In both apartments, the steel framing met minimum standards for EPS cladding support, but the overflow and pooling of water due to poor drainage and detailing was clearly evident.

Balcony Cavity Borescope Inspections

Using a borescope, the underside of the A4 balcony and parapet walls was also investigated. Moisture droplets, corrosion to joist welds, mould on the tile backer board, and laitance to the internal cementitious lining all pointed to balcony membrane failure and ineffective guttering. The original detailing had created conditions that allowed moisture to collect and remain trapped, contributing to corrosion and potential structural damage.

AAMA 511 Water Ingress Testing

Two rounds of forensic water testing were conducted on 14 June and 8 September 2023. Aamsko and Zenith followed the AAMA 511 testing protocol—based on ASTM E2128—which is designed to simulate real-world water exposure and trace active leak paths.

Key Findings from Testing:

• Unit 11C Lounge (Northwest Elevation):
  When water was sprayed at the top of the decorative corbel ledge on the floor above, immediate water ingress was observed. Water ran down the EPS board, pooling in the mid and lower horizontal steel framing.
  • Water droplets formed quickly inside the cavity.
  • Historic run marks and corrosion confirmed long-standing leaks.
• Unit 10C Second Bedroom (Northeast Elevation):
  Testing the same corbel detail from above (Unit 11C), water ingress occurred within two minutes, appearing through the ceiling of 10C.
  • Water overflowed from the C-section framing at 11C and tracked along the face of the concrete slab to present as drips below.
  • Importantly, no water ingress occurred through the window joinery, even though this had previously been suspected.

Photographs and diagrams captured the precise ingress path—starting at poorly detailed ledges and ending in rust-stained internal steel framing and saturated insulation materials.

Conclusions

This investigation confirmed that the majority of water ingress was not caused by vertical or horizontal panel joints, as initially suspected, but instead by the corbel ledges and EPS panel fixings that had been penetrated during historic installations or repairs. The problem was compounded by the absence of critical flashings and inadequate balcony drainage detailing. The invasive inspections and AAMA 511 testing eliminated guesswork. They provided clear, evidence-based findings that allowed Aamsko to develop a tailored remedial specification designed to resolve the building’s issues permanently—not patch over them.

Remedial Recommendations

Aamsko’s final recommendations included:

• Waterproofing the corbel ledges with a latex-based liquid-applied membrane (e.g. Tankit), with reinforcing mesh and sealants compliant with NZBC E2/AS1.
• Rebuilding the balcony gutters and falls to eliminate pooling and improve stormwater discharge.
• Recoating the entire cladding system with a crack-bridging elastomeric membrane (e.g. Dulux Acratex 968) to extend service life.
• Replacing rusted steel starter tracks and damaged EPS panels at lower floor levels, with careful use of EPS-safe adhesives and waterproofing.
• Installing the missing parapet cap flashings or equivalent waterproofing solutions to meet NZBC B2 durability requirements.

Final Thoughts

Aamsko’s role at Harbour Royal was not only to document the current state of the building, but to give the Body Corporate clarity and confidence. By combining architectural insight, forensic testing, and practical remediation design, we transformed assumptions into evidence—and guesswork into actionable plans. This is the heart of our service: helping Auckland’s apartment communities protect their assets and extend the life of their buildings, one careful diagnosis at a time.

📞 Contact us today to discuss a site-specific solution for your commercial building.

Aamsko New Zealand – Experts in Leaky Building Remediation Design, Contract Management, and Weathertightness Consultancy.