Historic Dublin building retrofitted with cutting edge insulation

Historic Dublin building retrofitted with cutting edge insulation

A landmark Georgian building on St Stephen’s Green has become the latest showcase for innovative sustainable building technology, as the Office of Public Works completes a major retrofit using Firetite aerated clay cavity wall insulation, supplied by Econ Building Products.

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The ambitious project at 51-52 St Stephen’s Green involved upgrading a 1970s extension behind the protected Georgian structure, presenting unique challenges for architects Heneghan Peng, the world-renowned architects behind the Giant’s Causeway Visitors’ Centre, the Palestinian Museum and the Grand Egyptian Museum. The team needed to improve thermal performance whilst maintaining the building’s fire safety standards and preserving its historic character.The retrofit covered approximately 2,000 square metres of cavity walls, with widths varying from 40 mm to 100 mm. Firetite innovative three-component mineral clay technology proved ideal for the sensitive historic setting.

The material offers excellent thermal conductivity of 0.034W/mK whilst achieving a Class A2-s1:d0 fire rating - eliminating the need for additional fire barrier retrofitting.

Crucially for the Georgian building’s preservation, the insulation is installed externally through small holes drilled in mortar joints, creating no internal pressure or damage to the original brickwork. The hydrophobic material also resists water passage, protecting the structure from moisture damage.

The project demonstrates Ireland’s commitment to sustainable building practices, with Firetite contributing thirty points towards BREEAM environmental ratings. The material’s Emicode EC1plus emissions classification ensures excellent indoor air quality for occupants.

Main contractor Duggan Brothers worked with specialist installer Ecospec Insulation to complete the retrofit, which forms part of the building’s transformation to meet nearly zero energy building (NZEB) standards. The successful completion positions the St Stephen’s Green building as a model for heritage building upgrades, showing how modern technology can enhance historic structures whilst respecting their architectural integrity.