Retrofitting Heritage Buildings For Energy And Seismic Upgrades PDF Download

Heritage conservation and energy efficiency considerations have converged in recent years. While new construction has focused on improved thermal performance to achieve high comfort levels in an energy efficient manner, the retrofitting of existing buildings with the same principles has just started to be recognised as a strategic measure, since they form much of the building stock and often have poor environmental performance. In this context, heritage buildings play an important role and have the potential to lead as best practices. In fact, given their cultural significance, they are the most likely to remain for a long lifespan, so their adaptation to future demands is highly important. Although energy retrofitting was considered a threat to conservation until recent decades, it has now started to be recognised as a measure to help with the protection of heritage, ensuring healthy indoor environments for a longer lifetime. In Aotearoa New Zealand, however, there is a gap between heritage conservation practices and energy efficiency considerations. Existing policies for the adaptation of existing buildings only focus on other types of upgrades, such as seismic strengthening, fire safety and accessibility. In terms of industry practice, most refurbishment projects only include shallow improvements, without making deep modifications to energy efficiency and indoor comfort. With the Building (Earthquakeprone Buildings) Amendment Act 2016 that took effect in 2017, thousands of buildings are required to be retrofitted over future years, including thousands Unreinforced Masonry Buildings (URM) of great historic significance. While the requirements are only related to seismic retrofit, there is now the opportunity to integrate thermal upgrades into these interventions, in order to improve the energy performance and usability of these buildings in the future. This research analysed the possibilities of including energy upgrades as part of the seismic retrofitting of URM buildings in New Zealand, proposing a range of levels of intervention, considering a respectful approach to heritage fabric. It provided insights into the current performance of URM buildings in New Zealand, revealing that there are significant issues in occupants' comfort and current building energy consumption. It then proposed energy retrofit scenarios, which ranged from less invasive interventions up to more comprehensive retrofit packages aiming to achieve the EnerPHit standard, developed by the Passive House Institute. These interventions were then analysed in terms of impact on energy performance and compatibility with heritage conservation principles, with an assessment based on European standard EN 16883. This analysis showed that it is possible to achieve higher energy performance in a sensible way in URM buildings, and that these upgrades can help these buildings continue to serve a useful purpose in a lowcarbon context. The combined seismic and energy retrofit of historic URM buildings in New Zealand can serve as an example for the management of historic heritage, demonstrating that an integrated approach can help achieve long-term benefits in the spheres of energy performance, seismic resilience and conservation of heritage for the future.