Australia’s first engineered timber office building has opened its doors at Sydney’s Barangaroo, just one year after construction began on site.

Developed by Lend Lease as the ‘front door’ to Barangaroo South, International House Sydney is built entirely of the industry’s ‘rising stars’ – Cross-Laminated Timber (CLT) and Glue-Laminated Timber (Glulam).

Project architects at Sydney practice Tzannes say the design and construction of the building, as well as the choice of building materials, were born from a big picture and first principles analysis – the project’s siting in the masterplan meant it had to demonstrate leadership in environmentally sustainable design and foster wellbeing for users.

“The architecture of International House Sydney reflects a new form of beauty,” says Alec Tzannes, the principle architect. “Beyond shape and surface, it is deep design renewing architecture’s role to serve the greater social purpose of lowering carbon emissions.”

Building with wood was a natural choice, with CLT and glulam both known to be highly sustainable materials from production through to construction.


The timber used for the project was sourced from certified, sustainably-managed forests, and prefabricated in a factory by Stora Enso in Austria. Prefabrication offers several benefits, such as sophisticated detailing, accurate fabrication, the creation of minimal material wastage, and the minimisation of schedule delays due to weather changes.

The engineered timber was then shipped to Australia and assembled on site.

“Even the construction was sustainable,” Barangaroo's managing director, Rob Deck, told Fairfax Media. “[Being] timber, it did not require drilling or concrete pouring, which made it a very quiet building site with minimal wastage.”

The speed of construction also meant less impact on neighbouring occupants and communities. 


CLT, also known as ‘pre-cast timber panels’, is created by stacking and gluing together kiln-dried timber boards laid at 90 degree angles to one another. These boards are hydraulically pressed to form solid structural wood panels, which can be used for floors, walls and roofs. More than 2,000m3 woth of CLT boards were used for the floors and cores at International House Sydney. 

Meanwhile, 930m3 worth of Glulam was used to construct the building’s columns and beams. Glulam is manufactured by gluing together smaller pieces of stres- graded and seasoned laminates, which are dressed to exact and uniform thickness. Because of the use of multiple laminates, glulam is usually stronger than solid timber. 

Reclaimed eucalyptus wood (Ironbark) was also used for the project’s striking two-storey wooden pilasters, which supports the slabs of prefab CLT construction.

“We have turned the structural limitations imposed by the use of timber to advantage and celebrated them, forming a unique colonnade form evocative of a forest of trees which gives the building its distinctive character,” Tzannes described.

“The result is a poetic and dynamic celebration of the building’s structural resolution, forming the street edge and undercover pedestrian network.”


As well as allowing faster construction times and lower carbon footprints, timber is also highly recyclable and can be made into other products at the end of a building’s lifecycle. Furthermore, engineered wood has great fire-resistant characteristics, with large timber beams proven to be able to retain their integrity even after being exposed to a fire.

On top of this, studies show that timber actually makes building occupants feel good. A 2015 report by Planet Ark found that being surrounded by wood at home, work or school has positive effects on the body, brain and the environment.

“The studies examining the effects of wooden rooms and furnishings clearly demonstrate that the presence of wood has positive physiological and psychological benefits that mimic the effect of spending time outside in nature,” Planet Ark said.

“The feelings of natural warmth and comfort that wood elicits in people has the effect of lowering blood pressure and heart rates, reducing stress and anxiety and increasing positive social interactions. Wood products within a room have also been shown to improve indoor air quality by moderating humidity.”



International House Sydney is not the first engineered timber building in the country – it is Lend Lease’s third after the Forte Apartments and Library at the Dock – and it certainly won’t be the last. In fact, there are several other projects underway that are also pushing the boundaries in the use of the material.

BVN, for example, made headlines in March for its plan to transform the old Telstra training centre building at North Strathfield, Sydney, with Glulam and CLT.

The 1970s concrete building, which is being converted for Our Lady of the Assumption Catholic Primary School, is expected to be the first “Australian school of the timber age”. It will be fit with a new Glulam portal frame, CLT walls and a unique CLT slab/acoustic ceiling system.


Lend Lease is also continuing to drive engineered timber innovations, delivering 5 King, the first engineered timber building in Queensland and the tallest in Australia, with Bates Smart. They are also confirmed for the Community Hub at Jordan Springs in Western Sydney, which is set to be the first public building in New South Wales to be built from CLT.


Although many of these projects continue to look outside of Australia to source for their engineered timber products, the market for wood is also burgeoning, with news of the opening of a local manufacturing plant.

New Zealand-based company, Xlam, is the first manufacturer of cross-laminated timber in the Southern Hemisphere. It is expected to open its first CLT manufacturing plant in Australia this year. The Albury Wodonga factory will be producing panels for construction by the close of 2017.

The facility will produce 60,000m3 of CLT each year and at capacity production will produce enough to build a project the size of Lend Lease’s Forte Apartments each week. The CLT will be made from local pine, and is expected to increase demand for the plantation industry, as well as shorten delivery times and distances for architects, developers and builders.


“For the first time, Australian builders will be able to choose a CLT product that is designed and made in Australia from Australian timber, meeting a significant demand in the current market,” XLam CEO Gary Caulfield said.

“It’ll also mean the jobs and proceeds stay in Australia, rather than going back to Europe.

“By building this facility in Albury Wodonga we’ll be in easy reach of Melbourne, Sydney and Canberra via the road and rail networks, and from there Australia-wide.”

Operational in mid-2017, the new facility will be the sole manufacturer of CLT in the country. Xlam currently has a number of Australian projects underway, including a CLT house designed by Fitzpatrick + Partners director James Fitzpatrick.