They are sustainable. They are portable. They are biophilic. And they can maintain a comfortable indoor temperature all year around. They are s.e.e.d. – sustainable environmental education spaces – designed by architectural firm Betti & Knut for the German International School Sydney (GISS) in Terrey Hills, NSW and built using cross laminated timber (CLT) to the international Passive House standard.

Based on biophilic design principles, the three new classrooms were conceptualised by architect Knut Menden as an interim solution involving portable classrooms while working on the GISS masterplan.

“We saw this as a challenge to rethink the much established ‘demountables’, which are a common feature of nearly every school in Australia, and achieve a modern solution aligned to our strong advocacy for sustainability,” Menden says.

“The goal was to build sustainable portable classrooms at a cost and time-frame equivalent to traditional portable classrooms, whilst also aiming for the international Passive House standard and use of timber as the primary construction material.

“The result of our design is s.e.ed. - a prototype for a new sustainable environmental education space as the antidote to traditional demountables,” he adds.

German International School Sydney

Each mass timber classroom measuring 85 square metres was prefabricated and preassembled offsite, and craned into place in 5 modules in less than 90 minutes per building.

The students enjoy fresh, clean air and thermal comfort year-round in the airtight Passive House classrooms, with heating and cooling demand reducing by 90 per cent, compared to a regular building.

According to the architects, the use of timber counteracts humidity levels to reabsorb humidity during wet weather and release in dry weather, naturally helping to create a balanced indoor comfort. “The use of timber internally and externally connects the buildings to the surrounding bushland setting, providing a calm natural interior that supports a positive learning environment for the students,” Menden explains.

Heat recovery ventilation (HRV) units supply clean and fresh filtered air to the classrooms, helping maintain a comfortable room temperature in hot and cold months, while also benefiting students with allergies. The HRV units are particularly helpful during bushfire season by keeping CO2 levels below the critical 800 ppm level inside the building.

German International School Sydney

The mass timber classrooms have already won the 2022 Sustainability Award in the Education and Research category as well as two awards at the 2022 Australian Timber Design Awards.

“We are very proud that our new classrooms have won the prestigious Sustainability Award. At our school we encourage forward thinking and sustainability, so to see this project being awarded with the highest honour for sustainable design and innovation in Australia is very rewarding and motivating for us all,” GISS principal, Dr Lorenz Metzger said after the Sustainability Award win.

“Considering the continued demand for portable classrooms across Australia in the foreseeable future, we hope to see these s.e.ed.s become an integral part of a sustainable growth strategy within the education sector,” Menden adds.

Photos: Betti & Knut