Buildings

ACADEMIC - PHD RESEARCH

Warm, Healthy, and Green Historic Buildings

Researcher: Rachel Paschoalin

Rachel Paschoalin’s PhD research looks at how renovation guidelines can be of benefit to create warmer and drier historic buildings. Her research investigates how to sympathetically retrofit historic buildings to reduce their energy use and greenhouse gas emissions so that they can continue our heritage, protect the climate, and serve their communities.

Rachel’s research is timely as it provides an alternative to the recent debates that saw historical character areas, like Mt Victoria in Wellington, accused of protecting damp, cold, and unhealthy rental properties from renovations. Over the past year environmental and rental organisations, such as Generation Zero and Renters United, submitted on the Wellington City Council's Spatial Plan consultation to reduce the size of character areas in order to enable more intensive, healthy development in inner-city suburbs. Much of their submissions argued that historical homes are cold, damp, and unhealthy. In her research, Rachel interviewed architects, conservation professionals, engineers, asset managers, planners, and policy experts to understand what retrofit measures are suitable under local best heritage practices. She explored whether New Zealand could benefit from adopting international procedures. "New Zealand's historic wooden buildings pose unique insulation difficulties. They often require carpenters with traditional skills, but our industry is small, making it harder to serve these needs at an affordable scale and cost”.

To develop guidelines, Rachel explored different retrofit measures while balancing the economic factors, heritage outcomes, and energy use. The measures range from installing roof and floor insulation, thermal curtains, installing double glazed windows, and various internal and external wall insulation options. Each has varying degrees of reversibility and appearance impact, so she is gauging their suitability from the expert interviews. Her initial findings identify that heritage experts are cautious with retrofitting’s visual, spatial and material impacts. Conservation professionals were hesitant to adopt overseas' guidelines if they potentially introduce unforeseen moisture decay of existing fabric and do not satisfy New Zealand’s unique climate, seismic, materials, and construction methods. Instead, her research found that guidelines should be tested locally along with training local experts before adopting such solutions. However, all the experts also appreciated the recent societal ambitions to reduce carbon emissions and ensure heritage and historic buildings are valuable contributors to the community they serve. “There is debate amongst experts between the macro-scale need to reduce energy use and increase liveability and the micro-scale goal to protect the historic building’s authenticity”, Rachel highlights. Rachel’s interviews have been recently completed and she is now developing best practice policy guidelines to inform construction, design, and government sectors in New Zealand. She will engage Heritage New Zealand Pouhere Taonga and conservation professionals to shape these specific local guidelines. She notes that “historic buildings should not be exempt from energy efficiency requirements, but policies should allow flexible targets, even if by little improvements". "Warmer and drier environments are possible through sensible changes that will noticeably enhance the environmental and liveability factors of historic buildings", she adds.

Rachel Paschoalin is a candidate in the Wellington Faculty of Architecture and Design Innovation under the supervision of Dr Nigel Isaacs and Dr Fabricio Chicca. Request that Rachel presents at your business or organisation. Email her on rachel.paschoalin@vuw.ac.nz or Dr Nigel Isaacs on nigel.isaacs@vuw.ac.nz.