OPW Kilcairn
A three-storey public office block
The OPW Kilcairn project is a Government Building accommodating staff from multiple government departments.
| Client | Office of Public Works |
|---|---|
| Duration | 42 weeks |
| Size/Area | 5000 m² |
| Value | €12 million |
| Architect | Cantrall Crowley |
| Engineering | Cora Consulting Engineers |
The OPW Kilcairn Government Building in Navan, Co. Meath is a three-storey, 5000 m² public office block accommodating staff from multiple government departments. Through an open, collaborative contractor lead design process, Sisk delivered a deep retrofit while the building remained fully operational.
Upgrades included improvements to the external envelope, enhanced roof and wall insulation, new glazing, and the installation of PV charging points. All works were completed within the OPW’s 42-week programme and allocated budget. Early contractor engagement enabled Stage 1 design to be completed in under two months, demonstrating the effectiveness of this approach.
Upgrades included improvements to the external envelope, enhanced roof and wall insulation, new glazing, and the installation of PV charging points. All works were completed within the OPW’s 42-week programme and allocated budget. Early contractor engagement enabled Stage 1 design to be completed in under two months, demonstrating the effectiveness of this approach.
The project successfully transformed the building’s performance, achieving a BER uplift from D1 to A2 and showcasing a model for decarbonising live public buildings as we strive to achieve our 2030 targets.
Driven by the Climate Action Plan and OPW targets, the project surpassed requirements by achieving a BER A2 rating. Key energy‑saving measures included:
- Wall Insulation: Upgraded external insulation to a U‑value of 0.35 W/m²K.
- Roof/Terrace Insulation: Improved roof insulation to 0.25 W/m²K, delivering major energy savings.
- Glazing: Installed double glazing (1.2 W/m²K, g‑value 0.40) to reduce solar gain and support natural ventilation.
- Lighting: Introduced LED lighting with daylight and occupancy controls.
- Heating: Replaced gas boilers with high‑efficiency air‑source heat pumps, aligning with the post‑2023 fossil‑fuel‑free target.
- Environmental Strategy: Adopted natural ventilation in place of mechanical systems, cutting heating and cooling demand.
- PV Panels: Added a 176‑panel (80 kWp) photovoltaic array to boost renewable energy generation and support the A2 rating.