Mannok Products and Technical Support Help Achieve Ireland’s First Gold Home Performance Index Certification

A development in Bray, County Wicklow is the first residential development in Ireland to be awarded gold certification under the Home Performance Index (HPI) for its quality and sustainability by the Irish Green Building Council (IGBC).

The housing development, designed by Coady Architects, consists of 40 homes, including a mix of apartments and terraced houses, and boasts estimated energy costs of just €65 per month for two- and three-bedroom units.

The HPI is Ireland’s national certification for new homes and is specifically designed for residential developments. It provides the most comprehensive measure of a building’s sustainability, looking at a range of factors in five categories: environment, health and wellbeing, economic, quality assurance and sustainable location.

The product selection and specification was key to successfully achieving the highest green home certification in Ireland, with several Mannok products specified and extensive technical support from the Mannok team, who worked closely with Senior Project Architect, Simon Keogh.

An important consideration for Keogh was the specification of products with Environmental Product Declarations (EPDs) as this is a specific indicator used in the HPI scoring system and essential to ensuring the sustainability of a building can be measured. Mannok products which were specified in the project thanks to their performance and because they each have EPDs published by the Irish Green Building Council include:

• Mannok Aircrete Thermal Blocks
• Precast Hollowcore Flooring
• Rathmore concrete Roof Tiles
• Mannok Therm Floor / MF PIR Insulation

Mannok Aircrete Thermal Blocks were used extensively to combat heat loss and improve the energy performance of the build. The blocks were specified in all floor to wall and ceiling to wall junctions in all 40 units of the development to address thermal bridging and reduce heat loss by up to 80% at these particularly vulnerable locations.

To help achieve gold certification, thermal modelling was completed by Mannok’s in-house National Standards Authority of Ireland (NSAI) accredited Thermal Modeller, Charlie Kane, who developed, optimised and approved the junctions of each unit to achieve a low Y-factor of 0.03 W/m²K.

The use of Aircrete Thermal Blocks for their insulating properties played a crucial role in achieving this low Y-factor, resulting in very little heat lost through the junctions of each unit, and subsequently reducing the monthly energy bills.

The impressive development was featured in a recent edition of Passive House Plus, which described it as a “pioneering project” which can help to “transform the industry” and stated that, along with a modulating heat pump and improved airtightness, Mannok’s thermal modelling and the resulting low Y-factor ensured the development “comfortably exceeds the headline targets of Ireland’s nearly zero energy building (NZEB) standard. The 40 units achieved average energy performance coefficients of between 0.19 and 0.21, representing between 79 and 81 per cent reductions in calculated energy demand compared to Ireland’s 2005 regulations.”

Under the headline “Measure Everything”, the detailed feature, highlights Simon Keogh’s meticulous attention to data and measurement, including his commitment to ensuring as many products as possible had EPDs in the build, and he has encouraged architects and everyone in the industry to do the same, stating,

“Ask for EPDs. Don’t specify a product until it has an EPD would be an ideal scenario…If we don’t measure something we cannot improve it. Developing high quality data is a critical first step in building more sustainable homes”.

With pressure on the industry to ensure we build in the most sustainable way possible, EPDs are an essential tool to measure the true environmental impact of the building, and Keogh’s view was echoed by Pat Barry, Chief Executive of the IGBC, who developed the HPI with Environmental Engineer, Neoma Lira,

“We have to build half a million homes over the next 20 years. That’s where most of the environmental impacts from construction will come from. That’s why it’s so important to measure the full impact of building ordinary housing…I applaud the diligence of the design team in sticking with the level of work that they put in to achieve [HPI] Gold. It’s a case of one person driving something single-mindedly and achieving it.”

Another important message highlighted in the Passive House Plus feature was the importance of not deviating from specified products on site, an issue which we have highlighted recently in relation to the substitution of thermal blocks on site.

“Going against the construction industry culture where the architect’s specification may be broken on site by contractors or subcontractors substituting an alternative non-approved product, Keogh was a stickler for evidence that the performance was adhered to, conducting regular site inspections to protect the specification, EPDs and all.”

Commenting on Mannok’s involvement in this leading sustainable residential project, the company’s Technical and Specification Manager, Jason Martin said,

“This development is a leading example of how careful specification and ensuring no deviation from the plan can achieve excellent performance, and I congratulate Simon Keogh and his team at Coady Architects on achieving the first HPI Gold certification in Ireland.

We are very happy to work with architects and specifiers on developments such as this to help achieve better performance through specification advice, calculations and thermal modelling where appropriate. Thermal modelling is a service which this project has benefited from by optimising the thermal performance at key junctions and providing data to support the HPI assessment. Whilst thermal modelling could cost developers thousands, with our in-house thermal modellers accredited by NSAI, we can provide this as part of a premium technical support package for larger projects where Mannok products are specified.

It is very positive to see the importance placed on EPDs in this build. It has been an area of focus for us since 2018 when we were among the first companies in Ireland to develop and publish declarations for our building products, and we have since gone on to develop EPDs for almost all our product lines. I am confident that we will see a lot more focus on the need for EPDs in the coming years and are keen to work together with architects who wish to use products with EPDs.”