Irish developer adopts Passivhaus standards at new housing scheme

Piper Square in Charlestown, Dublin is one of four residential projects under construction by Cairn, Ireland’s largest house builder. This site represents Cairn’s first attempt to deliver housing to the Passivhaus standard. Proctor Group is assisting the developer with this initiative.

Tightening the build

Over 1,700 units are expected to be completed by the first half of 2026. Approximately 600 units at Piper Square are scheduled to be ready for occupation by the end of 2025. Cairn acquired the site with planning permission for a scheme that was not originally designed with Passivhaus in mind.

The company carried out a feasibility study to determine what changes would be necessary to meet the higher standard. The study, published in Passive House+ magazine, noted that Cairn’s approach to meeting nearly zero energy requirements made the transition surprisingly attainable. An upgrade to triple glazed windows and minor adjustments to the floor and roof performance were the primary modifications required.

Wraptite carries Passivhaus certification, confirming it as a premium product suitable for Passivhaus construction. Its inclusion in the external wall design already highlights Cairn Homes’ emphasis on quality assurance, and it also illustrates why transitioning to Passivhaus certification proved simpler than might have been expected.

Technical execution

The membrane known as Wraptite provides airtightness while allowing vapour to pass, and it meets the W1 rating for water ingress. At Piper Square it worked together with an internal airtightness system, serving as a key element. By forming a weather-tight exterior, it reduces air movement inside the building envelope and prevents thermal looping, enabling the insulation to function optimally.

Using the WUFI® simulation tool, a full condensation risk study demonstrated that the suggested wall configuration poses no danger of moisture accumulation from condensation. Friday, 2nd October 2026 Proctor Group supports Irish developer to implement Passivhaus standards at Piper Square.