Seaton Beach

Case Study

Seaton Beach

The UK's first certified passivhaus plus multi-residential building utilises wienerberger's high-performing Porotherm solution.

Seaton Beach, Devon is the UK’s first certified Passivhaus Plus multi-residential building, comprising seven two-bedroom apartments and a three-bedroom penthouse. The carefully designed development prioritised innovation, health and wellbeing throughout its construction and was therefore able to go above and beyond the stringent requirements of the Passivhaus Standard.

As such, the project has been certified as a Passivhaus Plus home. The leading certification combines the minimal energy requirements of the Passivhaus standard with further on-site renewable energy generation methods. Now completed, the groundbreaking project is helping to reduce energy bills for its residents.

From an early stage of development, the client, Mike Webb at Seaton Beach Developments Ltd wanted the project to meet the highest standards of energy efficiency. With this ambition in mind, Mike reached out to the architect team of Gale & Snowden for its assistance. As architects, Gale & Snowden place a great importance on employing a fabric first approach to construction work.

On the Seaton Beach development, the architects worked to prioritise the construction and insulative composition of the property’s core elements, particularly its walls, while also employing a holistic approach to the building design. Thanks to this approach the team was able to deliver a sustainable and high-performing development.

View through glass windows to balcony overlooking the sea

Sunset view from balcony of Seaton Beach residential development

Seaton Beach building lit up in the distance from the beach at night

To ensure it achieved its overarching design and sustainability goals, the architect team chose to specify a modern clay block walling system, which it knew it could rely on; Porotherm. Previously, the team had used the innovative solution when working to complete similar major Passivhaus housing projects in Exeter, Bristol and Bournemouth.

At Seaton Beach, the team once again relied on this solution to deliver sustainable results. In particular, the project team utilised a monolithic clay block construction combined with a high-performance external render and internal plaster. On account of this decision, the structure’s wall build-up was mineral. In turn, this meant the development was hygroscopic, which helped to regulate internal humidity and promote optimum indoor air quality.

The team’s decision to employ this form of construction also enabled it to design the project around a large format block coursing. In turn, this then dramatically reduced construction time. Likewise, at the end of the building’s life, the structure can be crushed without the need for the separation and disposal of composite elements.

These benefits help to further reduce the building’s associated carbon footprint. Implementing measures that reduce carbon consumption is important in an industry like construction, which contributes to around 40 per cent of the nation’s total carbon emissions. What’s more, in light of the UK’s goal of achieving net zero carbon emissions by 2050 it’s increasingly essential that these more sustainable construction approaches become the norm.

Since its completion, the Seaton Beach project has gone on to be recognised with a number of prestigious awards, including:

Winner - Residential Project of the Year (35 units & under) – 2020 Michelmores Property Awards
Winner - Sustainability Project – 2020 Constructing Excellence South West Awards
Highly Commended - Sustainability Project – 2020 Constructing Excellence National Awards

As such, the project has helped to highlight what’s possible when development teams dually prioritise longevity and energy efficiency on large-scale builds. Additionally, the certified Passivhaus Plus project exemplifies the benefits of adopting a holistic approach to design and the positives of utilising modern, sustainable solutions, such as Porotherm.

View of the sea from the balcony of the new seafront development — © Dug Wilders

"The certified Passivhaus Plus project exemplifies the benefits of adopting a holistic approach to design

and the positives of utilising modern, sustainable solutions, such as Porotherm."

Porotherm is a unique clay block walling system, which offers a genuine alternative to concrete block construction.

The sustainable building material is helping to deliver exceptionally fast, virtually dry construction, which also benefits from high strength and thermal efficiency. A number of Porotherm blocks were used on the Seaton Beach project as well as a number of thermally broken lintels. These include T10 365 which is designed for monolithic construction, offering a climate regulating effect through the capillary block structure. PFZ 240, large chamber blocks for concrete filling and ZWP – Plan T 115 blocks for load bearing and non-load bearing interior walls.

The Porotherm clay block system offers a breadth of choice across two ranges; a core selection for interior walls in three width options of 100, 140 or 190mm and an extensive monolithic range serving both interior and exterior wall build ups with accompanying accessories. Both ranges can be used in conjunction, helping to give those using the solution more flexibility on projects.

Thanks to its lightweight nature, Porotherm is much faster to lay than traditional concrete blockwork; an average of 30/40 sqm per man, per day can be laid, which allows project teams to build to storey-height within just one day. Similarly, thanks to this easier installation process fewer people are needed on site, which reduces installation costs and makes social distancing regulations easier to uphold.

As well as being easier to install, Porotherm blocks are significantly safer for installers to work with. This enhanced safety is derived from Porotherm blocks being generally lighter than concrete alternatives. Additionally, unlike concrete, the clay block walling system doesn’t feature sharp corners due to its precision engineering and allows for mortar to be applied with a roller, which helps to reduce the risk of dermatological irritation for installers.

In turn, this advantage doesn’t only help to protect workers, but ensures that installations can continue to progress at a steady rate, with far fewer disruptions. Despite being lighter, the compressive strengths of Porotherm’s core range are typically 10 N/mm². As such, the range provides long-term, durable performance with a life expectancy of over 150 years.

However, on a project like Seaton Beach, perhaps the most important benefit of the solution was its impressive energy efficiency and sustainability credentials. Most notably, 30% of the materials used to create a Porotherm block are from alternative, recycled or secondary sources (MARSS). Additionally, solutions from the range are designed to be thermally and acoustically efficient, which allows them to deliver real value to tenants long after being installed.

Project Summary

Location: Devon
Client: Seaton Beach Developments Ltd
Architect, Passivhaus Designer: Gale & Snowden, project architect Lawrence Millyard
Main Contractor: Classic Builders

Awards and Accolades:

Winner of Residential Project of the Year (35 units & under) in the 2020 Michelmores Property Awards
Sustainability Project category winner for the 2020 Constructing Excellence South West Awards
Highly Commended - 'Sustainability Project' – 2020 Constructing Excellence National Awards