Services: Fire Protection

Isaac Theatre Royal

The Isaac Theatre Royal is one of Christchurch’s most iconic heritage buildings, and the Grade-A heritage listed theatre was badly damaged in the 2010 and 2011 Canterbury earthquakes. The project included the rebuild of a large portion of the structure while retaining the historic unreinforced masonry façade, ornate plaster ceiling dome and the entrance feature marble staircase.

Two major constraints on the project were the fixed $40M budget and the opening date for the first show. The theatre needed to be open for the 2014-2015 summer show season to keep key staff on. This required the design and construction to occur in two-thirds of the time of a conventional project. Holmes were the structural and fire engineers for the rebuild, and it became the first major entertainment venue to reopen for business in the CBD following the 2010 and 2011 earthquakes.

Fire Engineering

Holmes was brought into the project during construction to review the existing Fire Engineering Strategy provided by another consultant. Through performance based design we were able to present a robust solution on schedule and on budget.

The new Fire Engineering Strategy was produced within three months of engagement. The fire engineering design process also included:

  • Collaboration with the University of Canterbury to develop a new egress modelling tool for Holmes Fire use, which could undertake the buildings comprehensive egress assessment of merging crowd spaces;
  • Development of a fire strategy which considered an alternative compliance with the New Zealand Building Code in order to maintain the original architectural vision of a building designed over 100 years ago;
  • A hands-on approach to proactively integrate the Fire Strategy with the operational needs of the Theatre.
  • Consideration to Safety in Design, which included the physical practicality of installation and maintenance of the proposed fire strategy; and
  • Implementation of a complex fire and security interface which included multiple tests and training of theatre staff.

The design team had a vision of reviving the building to its original design including several key heritage features such as the auditorium dome and plaster detailing, marble stairs, and Edwardian façade. The dome and plaster detailing, in particular, relied heavily on our assessment.

Using smoke modelling tools, we were able to eliminate the need for the existing motorised smoke curtains covering the full width of the theatre adjacent to the dome. This also allowed the client to remove all of the access gantries and maintenance of the system.

Throughout the project, we were able to work collaboratively with the client to provide a unique, performance-based solution tailored specifically to the needs of the heritage building.

Structural Engineering

The tight construction period was achieved through the use of information sharing with the contractor and other consultants in the form of 3D Revit models, a close working relationship with the contractor, and looking outside the box in terms of materials (such as shotcrete) and construction sequencing.

The Theatre’s fixed budget consisted of insurance money and various grants and fundraising commitments. A key part of managing the budget was cost certainty during the design phases. The use of 3D drawings allowed the quantity surveyors to more easily identify pinch points and difficult areas, especially with regard to conflicts with heritage fabric. This helped to identify, manage and reduce these high risk cost areas throughout the project.

Nearly all the unique heritage features of this building were saved and carefully restored by skilled craftsmen—leaving the theatre in a better condition than it was pre-earthquake.

Auckland Art Gallery Toi o Tāmaki

The Auckland Art Gallery is an iconic and much-loved part of the city’s cultural heritage. When the gallery needed to seismically strengthen and refurbish the buildings, including fire safety design—which were built in 1888 and 1916 respectively—they trusted the challenging work to Holmes’ expert engineers. The final part of the work was to design new space to host an ever-growing number of exhibits. This project required the technical expertise to cope with a challenging seismic ‘retrofit’, combined with the ability to match the character and style of the new space with the existing structure. The existing building – one of the oldest in Auckland – was the first municipal art gallery built in New Zealand and contains the most valuable public art collection in the country.

Retaining the building’s heritage features, sensitive refurbishment and upgrading fire safety was of utmost importance. Key features of the architectural design include the impressive four storey north atrium and the three storey south atrium. The new and refurbished parts of the building required large, interconnected open plan spaces with a high degree of openness and visual connection to adjacent galleries and atria.

Fire Safety Design

The fire safety design involved a challenging mix of conflicting aspirations. As the building has to deliver specific performance requirements, the fire safety engineered solution was equally performance-focused: innovative to suit this client and this architectural design. The regulators expressed concern about the number of design issues that were required to vary from ‘standard fire approaches’ and insisted on an extreme level of engineering justification. Holmes responded with engineering design solutions that addressed the significant challenges of this unique architectural masterpiece.

The fire engineering brief evolved over five years, with contributions from art curators, gallery event managers, international exhibition advisors, architects, security consultants, structural and mechanical services engineers, Fire Service and Auckland Council regulatory reviewers. The final fire safety strategy successfully achieved the outcomes required by the fire engineering brief.

Holmes used computational fluid dynamics analysis to model smoke movement and also evaluated the movement of people in a fire emergency, using a variety of engineering building use scenarios for safety and robustness. The primary public circulation routes are also used as principal fire egress routes (allowing fewer dedicated egress stairs than prescriptive regulatory requirements). Holmes coordinated a detailed review of fire protection requirements in all areas storing and displaying art. Holmes designed the systems controlling fire and smoke spread to protect the building, the art collections and the building occupants. ‘Standard’ solutions for exit signage and security on exit doors were modified to suit the specific requirements for this building.

Seismic Strengthening

The seismic strengthening work started rigorous assessment of the building’s structural needs, drawing on market-leading modelling technology to identify potential weaknesses. The strengthening solution focused on minimising the impact on existing heritage features, creating a robust, resilient structure for the future. The new space included three galleries and two new roof level sculpture terraces, and the addition of a three storey glass atrium structure with a tension rod façade system and tree-like canopies that define and cover the entry forecourt, atrium and gallery areas.

B:Hive Smales Farm

B:Hive is taking commercial space to a new level offering shared office space that is fresh, vibrant and architecturally impressive! This new build construction has seven levels in total. One basement level (below ground) for car parking, one on-grade ground floor level which provides hospitality tenancy spaces, meeting room and breakout spaces, entry foyer and reception for the offices above. Above this are four levels of serviced office space leased on highly flexible short term and long term basis. The top-most level is dedicated for plant and building services.  

The 11,000 square metre building incorporates a diverse mix of office uses, with a mix of dedicated and shared spaces. It has the ability to house businesses from 10 to 310 employees per floor: from small startups to established corporates. 

Two features key to the design flexibility and interactive working environment are the open atrium and stair interconnecting all office levels and the ability for tenants to use flexi-space with up to 50% more occupants than a standard office building design. Using a novel smoke control strategy developed collaboratively with the day-to-day ventilation design, Holmes justified a fire safety solution which avoided the need for fire curtains or smoke separations around the atrium.

Pier B Extension, Auckland International Airport

Auckland Airport has a number of expansion phases planned and underway on its International Terminal. The expansion of Pier B added two new gates (17 & 18), increasing the number of international aircraft using the airport. The 190-metre extension enables Pier B with the flexibility to accommodate a total of four A380 or eight smaller A320 aircraft at any time. In addition, the Pier B bus lounge was expanded from two boarding gates to four, to allow greater ability to board flights using aircraft located away from the terminal.

The project challenge for Holmes was the delivery of the construction phase in five stages, whilst maintaining the continuous operation of the airport for commuters and staff alike. Construction involved temporarily relocating the principal three main egress stairs for Pier B and then reinstating these into the permanent design. All of this needed to be undertaken without adding significant cost through temporary works.

Working with interim strategies is a frequent request of our clients, where we need to strategise closely with our project stakeholders, ensuring smooth transition of construction through to operation whilst meeting adequate safety requirements through the entire process. In doing this we take to time to understand the constraints and provide options to ensure the most workable solutions are adopted.

Using performance-based design solutions for the project provided a more efficient egress design including reduced construction costs for the client where we enabled the elimination of stairs that were part of previous fire strategies.

Feature New Zealand landscape artwork and sculpture is also incorporated to the design, welcoming guests to this area of the international terminal which has also been fitted out with a new retail store and food and beverage outlet. Feature ceilings provided challenges to our fire protection design to ensure that sprinklers were installed to operate effectively, and without compromising the aesthetics.

ASB Waterfront Theatre

Located in Auckland’s popular Wynyard Quarter, ASB Waterfront Theatre is the first theatre in the Southern Hemisphere to be targeting a 5 Green Star rating for efficiency and sustainability. Offering a 650 seat theatre, it features a glass walled air bridge linking the theatre to the ASB Bank. The public artworks within the theatre have become a major attraction of the building’s design with one of the works featuring 10,000 LED lights, creating an image visible through the theatre’s glass wall.

The building was redesigned in 2012 after an initial preliminary design phase was put on hold. The new design was one of the first buildings in New Zealand to adopt the new C/VM2 Verification method for quantified performance based design. This new design approach was significant, as it allowed Holmes to develop a solution that did not require smoke detection nor a dedicated smoke extract system. This is of huge benefit to a performing arts theatre as it eliminates the risk of false activation of smoke detectors and smoke control systems as theatre effects use haze, dry ice, and artificial smoke. This solution also avoids the need to have an ‘isolate’ facility on the smoke detection and fire alarm system eliminating the need for the stage manager to monitor haze effects and other theatre-created environments which typically play havoc with smoke detection systems. Designing a fire compliant solution without a dedicated smoke extract system, activated with hatches and doors, avoided the inevitable potential compromise into what otherwise needs to be an acoustically sealed auditorium.

Key parts of the steel structure were assessed for adequate fire resistance without the need for passive fire protection, saving on construction cost.