MONOLITHIC ACOUSTIC CEILING SYSTEM ENHANCES HERITAGE BUILDING

Chancery House, Perth

Project

Refurbishment of Chancery House, cnr Howard Street & The Esplanade, Perth

Architect

Oldfield Knott Architects

Builder

Finlay Group Constructions Pty Ltd

Construction

2017-18

Products

USG Boral Ensemble System – including 220m2 acoustic plasterboards, DONN® Drywall Grid system, Fletchers 90mm-thick, 14kg/m3 glasswool and Ensemble Spray-Applied Finish

MONOLITHIC ACOUSTIC CEILING SYSTEM ENHANCES HERITAGE BUILDING

One of the Perth CBD’s most impressive heritage buildings, National Trust-classified Chancery House, has been refurbished as an office building. Originally constructed in the late 1920s, it’s Esplanade Street frontage housed the West Australian Turf Club. On the Howard Street side, retailers included a Rowntrees confectionary shop and several office suppliers, among others. Tenants of the three upper stories included the Naval & Military Club of WA, The Shakespeare Club, University of WA adult education services and a number of pastoral companies. In 1988-92 Chancery House was remodelled and additional stories added.

During 2017 its magnificent ground floor was renovated again, to provide an imposing foyer for office tenants and visitors. Obviously, the marble floor and atrium skylight would remain outstanding features. The question was, how to create the ambiance required in such a large open space filled with hard surfaces?

“To get a monolithic ceiling looking like that, and it’s also acoustic – we are very, very pleased with it.” - Roger Gregson, Oldfield Knott Architects

ACOUSTIC QUALITIES, HERITAGE APPEARANCE

Roger Gregson of Oldfield Knott Architects says, “We were looking for an acoustic ceiling material for this project, but it had to have the uniform appearance of a heritage ceiling.”

Heritage listing puts restrictions on altering a building’s interior as well as its exterior – which presented a real challenge, as acoustic ceiling products typically have a ‘modern’ perforated tile look. Roger says, “Given the heritage listing, we needed a smooth plasterboard appearance – but acoustic absorption involves perforations.” Fortunately, USG Boral was about to launch a new acoustic ceiling system in the Australian marketplace, which offers a cost-effective solution to achieving a monolithic appearance.

The Ensemble system enables architects to achieve a monolithic look in a ceiling in addition to a high level of acoustic qualities. It comprises several elements– all designed to work together to maximise NRC and CAC performance. Ensemble panels are uniformly perforated to absorb low- and mid-frequency sound upwards into the plenum space. Porous acoustical veils laminated to both sides of the panel help absorb high frequencies.

Another benefit of Ensemble for Roger Gregson was its speed of installation – the Chancery House project demanded a ceiling system which could be completed in a short timeframe.

The Ensemble panels are screw-attached to a ceiling suspension system such as Rondo KEY-LOCK® or Drywall Grid. For maximum sound absorption to fulfil the most demanding requirements, insulation such as glasswool is recommended for above the grid layer.

After panel installation, the system is completed with USG Boral Ensemble Spray-Applied Finish using a Graco GTX™ 2000 hopper – creating a monolithic appearance with tiny irregular perforations which allow sound to pass through.

“Once USG Boral showed us the possibilities of the Ensemble™ system, we realised the entire surface had the necessary acoustic properties. We could then apply a finished product over everything that’s up there to make it uniform and achieve the monolithic look we were aiming for. Ensemble fitted the bill perfectly.”

SIMPLICITY OF INSTALLATION

As Site Supervisor for the building firm, Finlay Group Constructions, Barry Milne seconds Roger Gregson. “The reason we chose Ensemble is for the simplicity of the installation, as it still gives the same acoustic qualities as a tile-and-grid ceiling system.”

As the refurbishment had to take place over the Christmas period when the building could be closed for a short period, the Finlay Group team was working day and night. This made the Ensemble six-step installation process preferable to comparable systems which involve 10-14 steps. The short drying time of 10-20 minutes between Ensemble finish coats (compared to a typical drying time of 4-24 hours) was another distinct advantage.

That said, Chancery House was the first project in Australia to use the new system, and the USG Boral team worked with the Finlay Group to smooth the process. “We were working with tools and a product that we’d never used before. The training that was provided on surface preparation, spraying and finishing by USG Boral was invaluable. After two days of training, we had no problems putting it into action on site,” Barry says.

MISSION ACCOMPLISHED

Standing in the impressive heritage Chancery House foyer on a busy afternoon, you can hear the difference. Roger Gregson says, “To get a monolithic ceiling looking like that, and it’s also acoustic – we are very, very pleased with it. You can just hear the difference in the voices; they just quietly get lost. The sounds of people coming in and out of the lift fall into the background, whereas before they were very resonant. That was the intention.”

“We chose Ensemble for simplicity of installation, as it still gives the same acoustic qualities as a tile-and-grid ceiling system.” -
Barry Milne, Finlay Group Constructions

 

For more information on the USG Boral Ensemble System visit usgboral.com/au/ensemble

Download the full case study here.