This one is about conservation-led retrofit and the retrofit of commercial (or institutional) building stock. We were invited to see a recent Iarnród Éireann (Irish Railway) retrofit project and meet with Heidi Hopper-Duffy (Environmental & Sustainability Manager) and its architect David Hughes (Senior Conservation Architect & Energy Specialist).Ostensibly, we're talking about energy efficiency and conservation of built heritage. The project was led by David, a retrofit of a historic building shared between Iarnród Éireann and the Chief Medical Officer's (CMO) office. We talk about it but you'll get to see the works in much more detail when Jeff features it in the pages of Passive House Plus. In this case, the railway, guided by David and Heidi's experience, can be lauded as a leader in its field and these sorts of projects are illustrative of the challenges and opportunities that come with working in a large company or institution.We also cover broader bits: design for deconstruction, BERs, what should we be quantifying i.e. carbon or energy, or what?Mind the background noise - we had a few unexpected background interruptions from an occasionally boisterous meeting room next door. Notes from the showIarnród Éireann and sustainabilityDavid Hughes on LinkedinHeidi Hopper-Duffy on LinkedInThe Train Drivers' building, as it appears in Passive House PlusThe National Inventory of Architectural Heritage (NIAH) for Ireland websiteThat awful retrofit cut out that Fionn Stevenson posted aboutThe Passive House Association of IrelandICOMOS Ireland (the International Council on Monuments and Sites) **SOME SELF-PROMOTING CALLS TO ACTION**We don't actually earn anything from this, and it's quite a lot of work, so we have to promote the day jobs.Follow us on the Zero Ambitions LinkedIn pageJeff, Alex, and Dan about websites, branding, and communications - zap@eiux.agency; Everything is User ExperienceSubscribe and advertise with Passive House Plus (UK edition here too)Check Lloyd's Substack: Carbon UpfrontJoin ACANJoin the AECB Join the IGBCCheck out Her Own Space, the renovation and retrofit platform for women (but not in a patronizing way)**END OF SELF-PROMOTING CALLS TO ACTION**