The completed project will be an exemplar, energy efficient, State office for occupation as a Headquarters Building by the lead Irish Government Department on the environment – the Department of the Environment, Climate and Communications. The works will consist of a significant upgrade to the 1970s building thermal fabric and overall energy use – that will upgrade the Building Energy Rating (BER) from a G rating to an A2 rating, resulting in over a 75% reduction of annual energy use and will greatly extend the buildings useful life.

The refurbishment will retain the existing 1970s structure, taking advantage of the energy already embodied in the concrete structure and brick external façade. By retaining and upgrading these resources rather than demolishing and rebuilding, the works will have significantly less impact on the carbon footprint of the building. Internally, the existing cellular office layout will be modified to a more open plan arrangement – increasing the overall building occupancy – while the introduction of a new central floor void will create improved daylight and natural ventilation conditions.

The embodied carbon in those existing structures will considerably mitigate the climate change impact of the investment when compared with any new build option. Use of heat pump technology and the application of the OPW’s Green Procurement Policy will also mitigate the climate change impact of the project.

On completion of this deep retrofit project, Tom Johnson House will act as an exemplar in the transformation of existing buildings for future use. The building, which is currently occupied by the Labour Relations Commission and the Geological Survey of Ireland, will become the new headquarters of the Department of Environment, Climate & Communications (DECC).