Sustainability in Heritage

WGE’s Perth team have been involved in a number of heritage projects, revitalising and restoring buildings that have often stood vacant for decades. Conserving and retaining heritage buildings is highly important in Perth, given so many buildings with heritage significance were lost in the development boom of the 1970s and 80s. Recent heritage projects by WGE include the transformation of Fremantle’s historic woolstores into Heirloom apartments, the COMO Treasury Hotel in Perth’s CBD, Old Perth Boys School at Brookfield Place, Sage Hotel in West Perth and Curtin Law School – revitalising the hundred-year-old former public health buildings at 57 Murray Street.

Why is sustainability important on heritage buildings?

Historic buildings need to meet today’s performance requirements in order to be comfortable for the occupants who live or work there.  Given that heritage buildings were not typically constructed with thermal insulation, adequate ventilation or natural light, achieving sustainability targets becomes a challenge.

What are the challenges?

Retaining heritage elements poses a challenge to achieving energy efficiency, effective heating and cooling, water conservation and wellbeing outcomes for occupants such as daylight and fresh air. Restoration is focused on maintaining and conserving heritage building fabric, so there are limited opportunities for insulation, thermal glazing and the addition of window shading. WGE’s approach is to look for solutions around the building elements that can be modified, often resulting in innovative outcomes.

Solutions and case studies

A recent insulation solution at a heritage warehouse converted to residential apartments utilised polystyrene balls instead of traditional blanket or panel insulation. WGE’s approach involved the careful creation of ‘pockets’ within the existing wall cavities of the heritage double brick walls that were filled with the polystyrene balls. This approach achieved the required level of performance without impacting on the buildings heritage brickwork.

At the award-winning COMO Treasury Hotel, the existing heritage windows did not meet thermal performance requirements. WGE’s innovative solution retained the heritage glazing and added a second layer of glass with a 100mm cavity. This approach boosted thermal and acoustic performance without touching heritage elements. The luxury hotel required extremely high standards of guest comfort to achieve a six-star hotel rating. The COMO Treasury Hotel was recently named the second best hotel in the world by Conde Nast Traveler.

Sustainability work undertaken at the Old Perth Boys School (constructed in 1854) focused on the life-cycle of the building. Sustainability outcomes were achieved by taking into account the reuse of an existing building as opposed to using new materials to build an equivalent. Calculations showed significant reduction in embodied carbon emissions due to re-use of an existing building compared with using new materials for a new building. The Old Perth Boys School demonstrated the sustainability advantages of heritage re-use of embodied energy, extending the life of the building and adding to the character of the city/built environment.