Kier Group sets Passivhaus standards for civic buildings

CGI of St. Sidwell's Point leisure centre in Exeter (Kier Construction)

We were delighted that Kier Group joined our 6th July ‘Sustainable Cities’ panel debate in our ‘Net Zero’ series as we move towards COP 26.

The discussion looked at how to build civic facilities to Passivhaus standards, the importance of influencing supply chains, the use of greener building materials and communicating with the end-users of buildings to maintain the long-term benefits of low carbon construction.

Kier has been commissioned to build a new leisure centre – St Sidwell’s Point – with two swimming pools in the middle of Exeter which is the first pool-leisure centre in the UK to be designed to Passivhaus standards. Procured through the Southern Construction Framework (SCF), it will replace an existing building and will incorporate a main swimming pool, a training pool, spectator area, café, fitness gym, health suite and spa facility. In order to achieve the stringent build criteria, Kier has worked closely with its subcontractors to deliver a ‘Passivhaus Passport’ training scheme, equipping staff with the knowledge and skills to meet these requirements.

St Sidwell’s Point is expected to attract 500,000 visits a year, twice the amount of the previous leisure facility. Due to the ultra-filtration, the pools will have exceptional water quality with minimal chemical content. The building has been modelled to withstand predicted changes in climate conditions up to 2080.

Jenna Bates, carbon manager at Kier Construction, commented:

“Exeter City Council wanted the leisure centre to be built with the same Passivhaus strategy that they are planning for all housing in the city. It will achieve 70 per cent energy reduction on an annual basis, with a concentration on ‘airtightness’ and the use of air source heat pumps. Climate change awareness is important too and with the expected changes in weather conditions we need to build with wider gutters.

“At Kier, it is important for us to embed sustainability as standard practice in everything we do and create buildings that minimise their impact on the environment. We need to build in new technologies, engage with our supply chain and make sure our colleagues are clued up on the sustainability agenda.

“It is vital to engage with our end users too. With the accent on airtightness at St Sidwell’s leisure centre, if someone leaves a door open that could be a problem, so there is an education programme to do. There always need to be conversations with the supply chain, and also a focus on site inductions with sub-contractors. We hope they learn lessons in sustainability that they can take to their next projects, even if they are not exactly of the same type.”

Jenna was then asked about how to build for longevity and the process of adapting buildings with the green agenda in mind.

She explained:

“Adapting buildings for sustainability and for longevity is important and it is vital how we engage and influence clients and their designers and embed that in each project. We need to design in layers so that replacing elements of a building can be done sensitively to create minimal damage. Ultimately buildings will come to the end of their life and be taken apart, but we need to make sure that the materials coming out of it can be re-used. We need to look at extending the life of a building and that depends on early engagement with the client and the supply chain. It is a two-way conversation and of benefit to the client. After all, we are all working towards the same goal of sustainability.

“Cost is one of the key issues which applies across the board. Are we willing to pay that cost and future-proof our buildings? Should we choose to invest and save costs ahead of time. One of the issues is the ‘newness’ of some materials. There is a lot of innovation in this area but not necessarily the testing requirements so that we can be confident in their use, so funding here is important. With time these things will come and with industry support.

“Heritage is also an interesting issue. Our client, the Crown Estate wanted to re-develop Morley House built in 1924 on Regent Street in London, keeping the façade and increasing the sustainability of this famous retail store. We put up a green wall - hanging on scaffolding - which increased biodiversity and minimized sound. All these measures create an effect on preserving the environment even if they are small.”

The Grade II listed façade of Morley House was retained while delivering a new core to the building, improving energy efficiency, and achieving a BREEAM 'Excellent' rating. The new development provides 1,021 square metres of high-quality retail space on ground and basement levels, as well as 44 new homes for market rent which will go on sale later this year.

The project has consisted of demolition behind a complex facade retention system, removing and storing the existing stonework facade and shopfronts for reuse.

Both The Crown Estate and Kier's commitment to sustainability and local community engagement were evident with Morley House achieving the equal highest Considerate Constructors Scheme score ever recorded in London and a high level of energy efficiency.

'Breathe' panels were installed throughout the redevelopment along Little Portland Street to absorb Nitrogen Dioxide, Sulphur Dioxide and benzene molecules from particles in the air. This enabled the team to measure emissions and through this, they were able to offset over 25 tonnes of CO2 through tree planting.

David McKenzie, managing director at Kier Regional Building London and South-East, said:

“We are delighted to have handed over another successful residential project, which demonstrates our capability in safely delivering a high- quality product with bespoke solutions for retained and heritage elements, to our client The Crown Estate.

“This project is testament to the team who have shown unrivalled levels of expertise and innovation throughout a particularly complex redevelopment project on a tight central London footprint. It also showcases our commitment to achieving our sustainability goals and helping our clients to achieve their own sustainability aspirations through the projects we deliver.”