Product Information

Specifying an external air barrier for the new Glass Bottle city quarter

Granted planning permission in March 2022, Phase 1 of Glass Bottle comprises three individual buildings with around 570 apartment units overall. 10% are social housing units and 15% are affordable housing units – percentages that will be maintained across delivery of the entire scheme, which will eventually deliver 3800 new homes for some 9500 people.

Phase 1 also includes a new creche and 400m2 of retail space. The external wall build-up of the apartment buildings is a fairly typical light steel frame structure with a sheathing board and external finish. Designed and specified by Dublin-based architectural practice Henry J. Lyons, the Wraptite external air barrier
was named within their specification pack.

As an airtight and vapour permeable membrane, Wraptite can be positioned to the external side of the structure. This moves the airtightness barrier away from the internal services zone, simplifying detailing and reducing the number of penetrations through the membrane. At the same time, allowing the passage of moisture vapour eliminates condensation risk.

It is even possible to use Wraptite as the sole membrane in a wall build-up, subject to the appropriate condensation risk analyses being carried out. However, at Glass Bottle, the Phase 1 specification still included an internal vapour control membrane as part of a belt-and-braces approach.

The residential apartments feature mechanical heat recovery ventilation, so an airtightness target of less than 3m3 /hr/m2 will be desirable. The better the standard of airtightness achieved on the project, the more efficiently the heat recovery ventilation will operate – and that all depends on the quality of the installation.

 

Installing Wraptite external air barrier on Phase 1 of Glass Bottle

The performance of Wraptite membrane is founded on it being a simple, self-adhesive solution, with the added benefit of Wraptite Tape being used for particular areas of detailing. This approach saves on the labour and material costs associated with meeting modern energy efficiency requirements, which are at the forefront of Glass Bottle’s conception.

Responsibility for installing Wraptite on Phase 1 of Glass Bottle fell to the subcontractors, Platt & Reilly Ltd. Talking about having experience of using different air barrier membranes, Project Manager Ionel Danaca explained what makes Wraptite different.

“We’ve found Wraptite is the easiest membrane to work with,” he said. “It’s the quality of the membrane and the quality of the adhesive – and not just that it is a self-adhered membrane, but the strength of the bond itself is superior.” Creating an entirely new quarter in a historic city like Dublin is no small undertaking. It means creating, from scratch, a community that is designed to integrate with the existing fabric of the city over decades and even centuries.

New residential development must be capable of standing the test of time, especially in the face of climate change. The three Phase 1 buildings have already been subjected to some severe weather during construction. Tony Ruth, A. Proctor Group’s Regional Sales Manager for Ireland, likened the rain to “monsoon” conditions, which the Wraptite had to bear the brunt of.

In part thanks to Wraptite’s W1 classification for water holdout, Platt & Reilly’s installation held up. “Over three floors, with thirty apartments per floor, there were just two small corners where some water ingress was evidenced – and even that wasn’t a failing of the membrane, but construction moisture which needed to dry out,” said Ionel.

Of course, product quality alone does not guarantee in-situ performance. Workmanship on site must be of a high standard too, and Platt & Reilly more than met their side of the bargain. A collaborative approach from both Platt & Reilly and A. Proctor Group has helped to get the best results during installation.

As Ionel Danaca described: “Tony has visited site several times and been really helpful. He made suggestions about installation relating to things like detailing around scaffolding, brackets and balconies, as well as how to get the most from the roller to bond the adhesive, and we implemented all of them.”

The benefits of this learning were quickly realised as Platt & Reilly moved from building 1 to buildings 2 and 3. Tony has been pleased to see the progress made and the performance achieved, even as construction work continues to take place:

“Platt & Reilly are proactive and helpful, so from my side it’s been about support and getting to site. You have to be there to support the best possible result, especially on such a landmark development for Dublin.”

Find out more: https://proctorgroup.com/products/wraptite