Wilkie + Bruce Architects
Christchurch, New Zealand
Knox Presbyterian Church was severely damaged following the 2011 Christchurch earthquake, which knocked down the walls of the church leaving only the ornate timber ceiling in place. The church has a rich cultural history, with some parts of the building dating from 1880. The rebuild required a carefully considered heritage sensitive restoration, combined with an earthquake-resistant design, whilst retaining its distinctive peaked roofline.
The pre-earthquake Knox Church did not provide ideal acoustics for unamplified music. Marshall Day Acoustics was given a clear brief:
- Excellent acoustics for the performance of unamplified music was the priority, however, music would occur as part of the liturgy and the space also had to be suitable for congregational singing
- Speech intelligibility, although an important requirement, was a secondary consideration to the performance of unamplified music
- Amplified music was to be acknowledged as a potential use, however this was not to form the primary focus of the acoustic design
A particular challenge was that there were no reliable room acoustic measurements of the pre-earthquake church. The amount of diffusion and absorption provided by the ornate ceiling was also uncertain. To overcome this, we drew upon measurements we had conducted at similar churches and cathedrals and we were able to accurately determine these effects within our model. Recommendations were also made with regard to bracing and wall construction to increase the low frequency reverberation time as much as possible.
The end result is a lightweight, modern interpretation of the original design, which fulfils the brief and provides seating for up to 400 people, with improved insulation, better accessibility and a new sound system.
- 2014, Canterbury Architecture Award
“Christchurch concert a success! We had a full house, the restored Knox church had such beautiful atmosphere, the acoustics were incredible and the musicians played with such enthusiasm, musicianship and virtuosity”.