Viden offers a range of seismic assessments & strengthening services designed to help commercial property owners protect their investments & ensure the safety of occupants
New buildings are built to meet robust seismic standards, but older structures often need extra protection.
Strengthening an existing building has many potential benefits:
Regulatory compliance
Better protection for occupants
Improved property value
Extending the life of the building
Lower insurance costs
Faster business recovery
Appealing to prospective tenants
We have successfully delivered a wide range of seismic strengthening projects throughout New Zealand and work closely with property owners/managers, real estate agents, architects and contractors to ensure that each project meets our client's unique needs and is delivered on time and within budget.
The ISA (Initial Seismic Assessment), DSA (Detailed Seismic Assessment), and design process are key steps to understanding and improving a building’s earthquake performance.
Below is a breakdown of what each stage involves and how Viden can help improve your building’s safety and resilience:
An ISA is an evaluation used to estimate a building's seismic performance.
It identifies the structure’s potential vulnerabilities and how it might perform during an earthquake. This assessment is often the first step in determining if a building meets acceptable safety standards for seismic events by comparing a building's % of structural earthquake strength relative to the NBS (New Building Standard).
An ISA does not typically involve detailed calculations or in-depth analysis. Instead, it gives a brief overview to confirm whether a DSA is required.
Stage 1: ISA
An ISA is often followed by a DSA, which is a more detailed analysis. However, some of our clients choose to bypass the ISA stage and move straight to the DSA and/or strengthening design phase.
The DSA determines the building's earthquake-prone status by assigning a New Building Standard (NBS) rating. In New Zealand, buildings that score less than 34% NBS are classified as ‘earthquake-prone’ and may require strengthening to meet compliance.
If a building is found to be earthquake-prone, the DSA will include recommendations for seismic strengthening to raise its NBS rating. This is essential to ensure the safety of occupants and meet legal obligations, especially for buildings in high-risk regions like Wellington and Christchurch.
Stage 2: DSA
After completing a DSA, the process of improving a building’s %NBS rating begins with a concept design. This outlines potential design solutions and provides enough detail for cost estimation. Once approved, the design is developed further into a detailed design, ready for construction. The final step is submitting this design to council and preparing for the construction stage.
Stage 3: Concept, Detailed Design and Consent
Throughout the construction stage, we are on-site, working alongside the contractor to ensure works are carried out according to the approved design and specifications. Once construction is complete, we provide a detailed report of all our inspections and a Producer Statement (PS4) confirming the works have been completed in accordance with our design.