Structural timber takeaways from our second Knowledge Breakfast

The impressive structure known as the Young Hunter House in central Christchurch was our venue for the second Joseph & Associates Knowledge Breakfast, which focused on structural timber design.

Joined on a frosty morning by building owner Tony Merritt, our guests were warmed by great coffee before heading inside the ground floor Matisse showroom to view the beauty of the raw timber construction. Here we listened to architect Jasper van der Lingen of Sheppard & Rout as he reflected on the challenges of erecting this unique building.

Speaker Jasper van der Lingen with Joseph’s Linda Lodetti

What makes it unique?

Well, as the structural engineer explained, this 3 storey, 1,900m2 commercial office building embodies two key engineering objectives: first, it is self-centring, and second, it dissipates energy.

• The structure uses PRESSS technology applied to laminated veneer lumber (LVL), meaning that should earthquake damage occur, it will be concentrated to replaceable ductile links.
• It is designed to experience repairable damage at code level seismic events.
• The building is capable of withstanding drifts associated with a 1 in 2,500 year seismic events.
• The outer tension and compression zones, externally mounted mild steel energy dissipaters, have been designed to hit first yield at a 1 in 500 year seismic event.
• Surprisingly, the cost of construction came in at less than $2,400 per m2.

Whilst these feats are innovative engineering principles, it is the pioneering determination of the building’s owner that should also be recognised. After the devastating events of 2011, Tony realised the importance of building a structure that could withstand earthquakes, or move and yield with their forces. He wanted a structure that would limit damage to essentially cosmetic repairs and minimise interruption, ensuring business could return to normal as quickly as possible.

Beautifully safe

It was late 2012, while we were still experiencing aftershocks, that the LVL structural post tensioned frame of the Young Hunter House was erected.  The building remains an exemplar project today due to the design principles, rapid erection, lighter weight and sustainability in the form of New Zealand harvested and manufactured building materials.

The result is an aesthetically pleasing ‘new heritage’ building that Tony Merritt’s grandson, who attended the breakfast, can be truly proud of; as indeed can Christchurch.

Looking to the future

As Jasper explained, the era of heavy-weight ‘muscle bound wrester’ structures is over. Moving forward we must focus our efforts on light-weight ‘ballerina-esque’ structures that can move and flex, so that we may work and play in the knowledge that we are safe.

To talk to the Josephs team further about timber construction in the implications from a project perspective, please feel free to contact Linda Lodetti via linda@josephs.co.nz

Thanks to Jasper van der Lingen and Tony Merritt for sharing their knowledge and experience, and to Matisse for sharing their elegant showroom. Joseph & Associates has created the Knowledge Breakfasts as we believe in sharing our passions and knowledge, new techniques and interesting ideas with our business community. To get involved or contribute, please contact us.

Warming up with coffee

Beautiful raw timber inside Young Hunter House

The striking exterior of Young Hunter House