OPW Technical Guidance: ‘Approaches to Improving the Energy Performance of Heritage Properties in State Care’

The Office of Public Works is responsible for managing the Government’s estate portfolio, including iconic heritage properties to the more every-day buildings for essential government and public services. The Governments Climate Action and Low Carbon Development Amendment Act 2021, the Annual Climate Action Plan (CAP), and the annually updated Public Sector Climate Action Mandate (Mandate) commit Ireland to a strategic direction to reducing greenhouse gas emissions by 51% by 2030 and achieving net-zero emissions by 2050.

With a significant holding of heritage properties and a commitment to improve energy efficiency across its portfolio, the Office of Public Works Heritage Services Unit identified a need for a detailed in-house technical guidance with a readily applicable and standardised process to apply to historic buildings of varying typologies.

The resulting new OPW technical guidance, ‘Approaches to Improving the Energy Performance of Heritage Properties in State Care’ provides a replicable methodology to assist with the assessment of existing building energy performance and the identification of energy efficiency improvement works that will provide the greatest energy efficiency benefits whilst respecting the heritage significance. It follows the process recommended by I.S. EN 16883:2017 ‘Conservation of cultural heritage - Guidelines for improving the energy performance of historic buildings’ and provides practical advice on the steps necessary to arrive at rigorously assessed and suitable solutions tailored to each individual building and its particular requirements and constraints.

The guidance is supported by two energy upgrade case studies to demonstrate the recommended approach in practice; 1) a typical Georgian terrace at No. 7 Merrion Square, Dublin 2 and 2) a former army barracks at the Block M Offices, Dublin Castle, both in use as offices.

As increased attention is placed on improving the energy efficiency of the worst performing buildings, many of which are believed to be traditionally-built, guidance was urgently needed to consolidate existing knowledge and experience into a holistic energy renovation methodology for OPW architects to assess and adapt heritage properties for improved energy performance. Whilst the technical guidance was written to assist OPW architects with the energy renovation of historic properties in state care, the OPW have decided to share the guidance and case studies more widely to broaden industry-wide technical expertise and support broader public and private sector initiatives in meeting National and EU carbon emission reduction targets for the existing built environment.